Contents - Geo-EM 2017gem2017.org/Program Book.pdf · 2 Contents Preface from the Chairman of the...

2

Contents

Preface from the Chairman of the 1st Geo-EM 2017 1

Preface from Head of Applied Geophysics and Exploration Expertise Group 2

ITB Campus Map 3

Field Trip Destination Preview 4

Program Schedule 5

Poster Schedule 9

Abstracts of Keynote Speakers 20

Abstracts of TM Group (Theory, Modeling, and Inversion) 28

Abstracts of OG Group (Geophysical Exploration, Oil, and Gas) 36

Abstracts of NR Group (Geophysical Exploration for New and Renewable Energy) 42

Abstracts of EV Group (Environmental Geophysics) 50

Abstracts of EG Group (Engineering Geophysics) 61

Abstracts of TH Group (Tectonic and Monitoring Hazard) 71

Abstracts of RM Group (Rock Magnetic) 81

3

Committee

General chair Dr.rer.nat. Widodo, ST, MT

Steering Committee Members Prof. Sri Widiyantoro, Ph.D

Prof. Dr. Ir. Djoko Santoso

Prof.Dr. Wawan Gunawan A. Kadir

Dr.rer.nat. Wahyudi W. Parnadi

Dr. Susanti Awaliyah

Dr. Hendra Grandis

Dr. Daharta Dahrin

Dr. Andri Dian Nugraha S.Si, M.Si

Dr. Agus Laesanpura

Dr. Warsa, S.Si., MT

Program Committee Members Dr. Setianingsih

Dr. Eko Januari Wahyudi, ST., MT

Ir. Indra Gunawan, M.Sc., M.Si

Dadi Abdurahman, ST., MT

Silvia Jannatul Fajar, ST., MT

Kartika Hajar Kirana, S.Pd., M.Si

Azizatun Azimmah

Siti Nurjanah

Ridho Nanda Pratama

Nadia Amalia

Erisha Aryanti

Rifki Mega Saputra

Rianty Kusuma Dewi

Febri Taufik

Indriani Yunitasari

Sevi Maulinadya

Kana Agatha Natania

Kuto Hillary

Gatot Nugroho

Arifa Hijriani

Probo Mukti

Andrianus Boas

Muhamad Lutfi Ramadhan

Liaison Officer (LO) Sevi Maulinadya

Nur Rachmad Madyantara

Nadhila Hizhwati

Chairul Rajib

Okta Indah Sulistyorini

Tara Annisa

1

Dear Participant,

On behalf of committees, I would like to welcome you to The 1st Geo-Electromagnetic (Geo-EM) Workshop

2017 here in Bandung, Indonesia. It is an honor for me to be the chairman of this workshop. Geo-EM workshop

is a biennial event held by Applied Geophysics Department, Geophysical Engineering, and Institut Teknologi

Bandung. This first ever Geo-EM workshop is focusing on theories and applications of geoelectrical science,

electromagnetic, and rock magnetic in the field of geosciences, engineering, environment, geotechnical, and

exploration of natural resources. Although, this is the first-time Geo-EM has been held, it is participated by

many from scientist and engineer. At least more than a hundred of abstracts are submitted, not only from

Indonesia, but also from overseas such as Malaysia, Thailand, Japan, China, Africa, Germany, France, Russia,

and many more. This is beyond our expectation and target.

This 1st Geo-EM Workshop with the theme “Development and Application of Geoelectric-Eletromagnetic and

Rock Magnetic Methods for Earth Resources Exploration”, is meant to encourage the development and

application of geo-electric & EM methods and rock magnetic to support sustainable energy in the fulfillment of

the human needs. It also has a wide meaning in environmental conservation and monitoring efforts in an attempt

to minimize the disaster victims, especially in Indonesia. To this, in this workshop we hope for participants to

share their knowledge, ideas, and develop new methods particularly in rock magnetic, geoelectric, and

electromagnetic field. Following the participant’s presentations we expect all presenters to submit their extended

abstract which then will be published in international conference proceeding indexed by SCOPUS.

This workshop will be held for five days including a course collaborating with Society of Exploration

Geophysicist (SEG) in Distinguished Instructor Short Course 2017 with the topic of Geophysical

Electromagnetics: Fundamentals and Applications and will be presented by Professor Doug Oldenburg on

February 20th

, 2017. The courses then continued by workshop for the next three days after on February 21st-23

rd,

2017. Lastly, on February 24th

we will be having a field trip to Mount TangkubanPerahu, tea walk among the tea

gardens, and enjoy the breathtaking view of CurugDawuan, and relaxing visit to a hot spring spa in

GraciaSubang.

We would like to thank all sponsors, Institute of Research and Community Services (LPPM) – ITB, Faculty of

Mining and Petroleum Engineering – ITB, Geophysichal Engineering- ITB, LAPI-ITB, Institute of Geophysics

and Meteorology (IGM), University of Cologne, Ocean University of China, Soceity of Exploration

Geophysicist (SEG), Honda, Villa Cisitu Indah 6 No. 17, PT. Kuarsa Hexagon, KMS Technologies, Premier

Oil, Semen Indonesia, Wardah, KMS Technologies, and all donors that participated to this workshop. Thanks to

all students of Geophysical Engineering-ITB that supported this event. To all committees, my highest

appreciation for the hard work in creating this workshop. I hope everyone enjoy their stay in Bandung, connects

with new colleague from across nations that enrich the knowledge in our workshop.

Chairman Geo-EM Bandung 2017

Dr.rer.nat. Widodo

2

Dear all colleagues,

On behalf of Head of Applied Geophysics and Exploration Expertise Group, we would like to welcome you to

The 1st Geo-Electromagnetic (Geo-EM) Workshop 2017. This workshop is one of the acts to empower and

enhance research performance, community service, and innovation particularly in application and development

of knowledge in geophysics. Hopefully the theme “Development and Application of Geoelectric-Eletromagnetic

and Rock Magnetic Methods for Earth Resources Exploration” this workshop will support collaboration,

sharing, and innovation development in application of knowledge particularly in rock magnetic, geoelectric, and

electromagnetic field.

This workshop is expected to be held continuously, that it will be the main program of our Expertise Group and

held biennially. It is an honor for us that there are many participants in this workshop not only from Indonesian

institutions, but also from nine other countries from Asia, Africa, America, and European continents. This will

bridge further collaboration in research, innovation, and enhancement in human resources.

I thank all sponsors for the support towards this event. To all committees and students, my highest appreciation

for the hard work and support from the very beginning to the very end of this workshop. Lastly, I thank

scientific reviewers and all participants that contributed in this workshop whether it is poster or oral

presentation.

Please enjoy the ideas and development of knowledges that could enhance and compliance human life and the

environment. Make this workshop a medium to seek new friends, collaborate, and bridge knowledge.

Head of Applied Geophysics and Exploration Expertise Group,

Prof. Dr. Djoko Santoso

4

Tea Walk

Curug Dawuan

5

PROGRAM SCHEDULE

DISC (Distinguished Instructor Short Course )

Monday, 20 Feb 2017

7.00

8.00

Registration & Ice Breaking

8.00

16.00 Geophysical Electromagnetics: Fundamentals and Applications

( Prof. Doug Oldenburg and Sogie Kang)

PROGRAM AND ORAL SESSIONS

Tuesday, 21 Feb 2017

7.00

8.00

Registration & Ice Breaking

8.00

8.45

Opening Remarks

8.45

9.45

Keynote Prof. Dr. Bülent Tezkan (Universität zu Köln, Germany)

9.45

10.00

Coffee Break

10.00

10.45

Keynote Prof. Dr. Ir. Djoko Santoso, M.Sc. (Institut Teknologi Bandung , Indonesia)

10.45

11.05

Oral Presentation I: Nazli Ismail, Muhammad Yanis, Muyassir (Imaging the Northern part of t Great Sumatran Fault system based on 2D Inversion of Magnetotelluric Determinant data)

11.05

11.25

Oral Presentation II: Febriani, Widarto, Gaffar, Nasution, and Grandis (Subsurface Structure Imaging of the Sembalun-Propok Area, West Nusa Tenggara by using the Audio-frequency Magnetotelluric Data)

11.25

11.45

Oral Presentation III: M. Jinmin, S. Rosli, M. M. Nordiana, S. Mokhtar (Trilogy Possible Meteorite Impact Crater at Bukit Bunuh, Malaysia using 2-D Electrical Resistivity Imaging)

11.45

12.45

Lunch

12.45

13.30

Poster Introduction

13.30

14.30

Poster Presentation

14.30

14.50

Coffee Break

14.50

15.10

Oral Presentation IV: Hidayat, Asep Rohiman, Saultan Pandjaitan (Identification of Pre-Tertiary Deposit by using Magnetotelluric Method in Bintuni Basin, West Papua, Indonesia)

15.10

15.30

Oral Presentation V: Teuku Abdullah Sanny (Identification of Fault Structure along Jakarta-Bandung High Speed Train Railway by Using CSAMT and Seismic Tomography Methods)

6

15.30

15.50

Oral Presentation VI: Hazrul Hisham, M.M. Nordiana and Teoh Ying Jia (The Study of Mudrocks Resistivity in Northwestern Peninsula Malaysia using Electrical Resistivity Survey)

15.50

16.10

Oral Presentation VII: Jaingot A. Parhusip, Agung Harijoko, Doni Prakasa E.P., Wiwit Suryanto (Assessment of Leachate Infiltration from Piyungan Landfill using Electrical Resistivity Method)

Wednesday, 22 Feb 2017

7.30

8.00

Opening Remarks

8.00

8.45

Prof. Doug Oldenburg (Invited Speaker)

8.45

9.05

Oral Presentation I: Bryna Mustika and Niken Ramadianti (3-D Modelling for Exploration Iron Ore in Tanjung Mahuroy Village, Central Kalimantan using Geoelectrical Method IP and Dipole-Dipole)

9.05

9.25

Oral Presentation II: Agus Laesanpura and Warsa (Resistivity and Gravity Data for Aquifer Modelling in Kendari (South Sulawesi) )

9.25

9.40

Coffee Break

9.40

10.25

Prof.Satria Bijaksana (Invited Speaker)

10.25

10.45

Oral Presentation III: Pranitha Septiana, Siti Zulaikah, Arif Hidayat, Rosyda Azzahro (Magnetic Susceptibility and Dielectric Properties of Peatland in Central Kalimantan, Indonesia)

10.45

11.05

Oral Presentation IV: Siti Zulaikah, Dian Sisinggih, Zem Dani, Mahfud David Ong, and Yusuf Bungkang (Magnetic Susceptibility, Fe Content and Morphology of Magnetic Mineral extracted from surface sediment of Kamp Walker and Hubai River as an Inlet of Sentani Lake, Papua-Indonesia)

11.05

11.20

Poster Introduction

11.20

12.20 Poster Presentation

12.20

13.20 Lunch

13.20

14.05

Prof.Weerachai Saripunvaraporn (Invited Speaker)

14.05

14.25

Oral Presentation V: Wahyu Srigutomo and Ariel A. Rahardi (Numerical Techniques for Solving Gauss Quadrature Semi-infinite Integral used in Vertical Magnetic Dipole Forward Modeling)

7

14.25

14.45

Oral Presentation VI: Ida Bagus Suanadna Yogi, and Widodo (Time Domain Electromagnetic 1D Inversion using Genetic Algorithm and Particle Swarm Optimization)

14.45

15.05

Oral Presentation VII: Agus Setyawan, Nur Rachmaningtias, and Imam B. Raharjo (Two-Dimensional Inversion Finite Element Modeling of Magnetotelluric Data at “J” Geothermal Area, Indonesia)

15.05

15.20

Coffee Break

15.20

15.40

Oral Presentation VIII: Yunus Daud, Wambra Aswo Nuqramadha, Fikri Fahmi, Surya Aji Pratama, Khalif Radhiyya Rahman3, Wisnu Subroto (Discovering “Hidden” Geothermal Reservoir in Blawan-Ijen Geothermal Area (Indonesia) Using 3D Inversion of MT Data)

15.40

16.00

Oral Presentation IX: M.M. Nordiana, Rosli Saad, I.N. Azwin,and Andy A. Bery (Determination of Slope Failure using 2D Resistivity Method)

16.00 16.20 Oral Presentation X: Y. C. KIU, S. ROSLI1, I. N. Azwin, S. Mokhtar (The General Indications of An Impact Crater using Integrated Geophysical Methods)

Thursday, 23 Feb 2017

7.30

8.00

Opening Remarks

8.00

8.45

Prof. Yuguo Li (Invited Speaker)

8.45

9.05

Oral Presentation I: Yuri A. Agafonov, Igor V. Buddo, Olga V. Tokareva, M. Shukur M. Ali, Mustapha M. Salleh (Application of TEM Technique in South-East Asia)

9.05

9.25

Oral Presentation II: Sintia Windhi Niasari (Resistivity Image Beneath Parangwedang Geothermal Field (Indonesia) Inferred from Magnetotelluric Data)

9.25

9.40

Coffee Break

9.40

10.25

Dr. Amir Haroon (Invited Speaker)

10.25

10.45

Oral Presentation III: R. Aftartu, S. Davydycheva, and K. Strack (Uses of Lotem for Indonesian Hydrocarbon Applications)

10.45

11.05

Oral Presentation IV: Andri Yadi Paembonan, Sonya Davydycheva, Maxim Smirnov, Rungroj Ajdwech, Kurt M. Strack (An Application of LOTEM around Salt Dome near Houston, Texas)

11.05

11.20

Poster Introduction

11.20 12.20 Poster Presentation

8

12.20

13.20 Lunch

13.20

14.05

Dr. Kurt Strack (Invited Speaker)

14.05

14.25

Oral Presentation V: Sirelkhatim H. Mukhtar (Time Domain Electromagnetic Survey for Geotechnical Exploration at Singa Substation)

14.25

14.45

Oral Presentation VI: Muhammad Hasbi Assiddiqy, and Warsa (Reservoir Identification using Short Offset Transient Electromagnetic Method)

14.45

15.05

Oral Presentation VII: S. Nabila, M.M Nordiana, I.N Azwin and Mokhtar Saidin (Analyzing Soil Electrical and Strength Parameters using Geophysical Methods in Sungai Batu, Kedah)

15.05

15.20

Coffee Break

15.20

15.40

Oral Presentation VIII: Azim Hilmy Mohamad Yusof , Muhamad Iqbal Mubarak Faharul Azman, Nur Azwin Ismail, Noer El Hidayah Ismail, (Applying 2-D Resistivity Imaging and Ground Penetrating Radar (GPR) Methods to Identify Infiltration of Water in the Ground Surface)

15.40

16.00

Oral Presentation IX: A. N. Nordiana, and M. M. Nordiana, Teoh Ying Jia (Application of Geosciences Parameters in Identifying Rock Properties at Bukit Chondong, Malaysia)

EXCURSION Friday, 24 Feb 2017

6.30

AM Depart from ITB to Tangkuban Perahu Vulcano

7.30

AM Arrive at Tangkuban Perahu Vulcano

10.00

AM Enjoy Vulcano and Landscape

10.30

AM Visit Rain Fall Curug Dawuan

11.00

AM Tea Walk

12.00

PM Visit Hot Spring Spa

12.30

PM Have Lunch at Gracia Hot Spring Spa

1.30

PM Enjoy Hot Spring Spa

4.00

PM Depart from Gracia

5.30

PM Arrive at ITB

9

POSTER SCHEDULE

No Name of Author(s) Institution Code of Abstract

Title

Tuesday, 21 February 2017

1 Rahmat Fajri, Amajid Sinar, Kevin Hartono, Indriani Yunitasari, Widodo

Geophysical Engineering, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung

EG-01 Underground Infrastructure Detection using Ground Penetrating Radar Method

2 M Fariz Gumai, Stephen Fernando, Gatot Nugroho, Kana Natania, Widodo


EG-02 Quality Investigation of Building Structure using Ground Penetrating Radar Method which is Effective and Enviromentally Friendly as An Early Study to Prevent Severe Structural Damage

3 Erina Prastyani1, Sintia Windhi Niasari2

Program of Geophysics, Universitas Gadjah Mada, Indonesia; 2Geophysics Sub-Department, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Indonesia

EG-03 Interpretation of VLF-EM & VLF-R Data Using Tipper and Impedance Analyses: A Case Study from Candi Umbul-Telomoyo, Magelang, Indonesia

4 Adella Putri Affanti1, Sinthia Windhi Niasari2

1Undergraduate Program of Geophysics, Universitas Gadjah Mada; 2Geophysics Sub Deartment, Universitas Gadjah Mada

EG-04 VLF EM and VLF R Modelling using 2layinv and Karous-Hjelt MATLAB in Candi Umbul Magelang

5 Puspita Dian Maghfira, Sintia Windhi Niasari

Geophysics Sub-Departement, Faculty of Mathematical and Natural Sciences, Universitas Gadjah Mada

EG-05 Analysis Magnetic Data to Indetification Structure in Candi Umbul Geothermal Prospect Area, Central Java

6 M. Dika Arzaldi, M. Izzuddin Prawiranegara, Emirza Faisal D., Arzalia Wahida, Widodo


EV-01 Investigation of Cikapundung Rivers Sedimentation using 2D Resistivity Method

7 Arifa Hijriani, Aji Surya Utama, Andrianus Boas, M. Ridho Mukti, Widodo


EV-02 Plug Identification in Drainase System Using Electromagnetic Wave

10

8 F. N. Izzati, Z. S. Laksmana, B. Marcelina, S. S. Hutabarat, Widodo


EV-03 Identifying Potential Ground Movement as A Landslide Mitigation Approach using Resistivity Method

9 Rianty Kusuma Dewi1, Adityo Kurniawan1, Reyhan Fariz Taqwantara1, Farras M. Iskandar1, Taufiq Ziyan Naufal2,Widodo1

1Geophysical Engineering; 2Geological Engineering, Institut Teknologi Bandung

EV-04 Innovation in Evacuation of Natural Disaster with GPR Method

10 Erisha Aryanti, Ahmad P. Ardi, Muaz Almunziri, Zael Yahd Xanggam, Adino Eleazar, Widodo


EV-05 Waste Disposal Mapping with Electrical Resistivity Tomography, case: Leuwigajah Landfill

11 Wiwid Joni1,2, Darharta Dahrin1, Asep Sugianto2

1Geophysical Engineering, Institut Teknologi Bandung, 2Geological Agency of Indonesia

NR-01 Delineation of Dolok Marawa Geothermal Prospect Area by Applying 2-D Inversion that Utilize Magnetotelluric, Audio Magnetotelluric, and Time Domain Electromagnetic Data

12 Achmad Fajar Narotama Sarjan, Sintia Windhi Niasari

Geophysics Sub-Departement, Faculty of Mathematics and Natural Science, Universitas Gadjah Mada

NR-02 Measurement of Subsurface Structures in Telomoyo Mountain Geothermal Area, Magelang using, 1-D Audio Magnetotelluric Method

13 Kevin Gardo Bangkit Ekaristi, Aditya Aries Furkhan, Agra Adipta

Geophysical Engineering Department, Pembangunan Nasional University Yogyakarta

NR-03 The Revealation of Structure Controlled Hotspring using Passive Single Component Electromagnetic Method

14 Muhammad Bisri Mustofa, Umar fauzi, and Fourier D. E. Latief

Earth Physics and Complex Systems, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung

OG-05 Formation Factor Calculation of Digital Rock Images with the Help of FEM

15 Donny Prasetyo1, Warsa 1), Wahyu Srigutomo2) and M. Rachmat Sule1)

1Geophysical Engineering Department, ITB; 2Physics Department, ITB

OG-07 Non-linear Inversion Modeling of TDEM Data for Reservoir Characterization

16 Yovan Prananda1, Febri Taufik1, Alief Rizki1, Fikrianti Surachman2, M Hardian T3, Naufal Rachman Akbar4, Widodo1

1Geophysical Engineering Institut Teknologi Bandung, 2Pharmaceutical Care Institut Teknologi Bandung, 3Chemistry Institut Teknologi Bandung, 4Biology Institut Teknologi Bandung

RM-01 Pollution Detected Innovation of The Hazardous and Toxic, Subtance Disposal by Magnetic Susceptibility Method around Cikijing River, Rancaekek for Testing Water Quality Standards

11

17 Ganendra Chandra Ditya, Arno Germanndaputra Sulistyanto, Satria Bijaksana


RM-02 Construction of An Inexpensive Field Gradiometer based on FGM3-sensor and SCL007 IC Chip

18 Mariyanto, Satria Bijaksana


RM-03 Magnetic Properties of Deposited Sediments in Surabaya River, East Java, Indonesia

19 Abd Mujahid Hamdan1, Satria Bijaksana1, Aiyen Tjoa2, and Darharta Dahrin1

1 Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung 2Agriculture Faculty, Tadulako University

RM-04 Low-Temperature Thermomagnetic Method and identification of Impurities in Ni Hyperaccumulator Plants

20 Sevi Maulinadya, M. Lutfi Ramadhan, Nanda Wening F., David Pinehas, Widodo


TH-01 Lembang Fault Plane Identification using Electrical Resistivity Tomography for Disaster Mitigation

21 Selvi Misnia Irawati, Dina Sari Handayani, Wahyu Kusdyantono

Geophysics Study Program, Department of Physics, Universitas Gadjah Mada

TH-03 Magnetotelluric Data Analysis in Cascadia Subduction Zone, USA

22 Irwandi, Marwan, Muksin

Syiah Kuala University TH-04 Applications of the VLF induction Method for Rapid Sumatran Fault Identification in Leuser National Park, Aceh

23 Wen J Whan 3Jtech TM-01 Magnetotelluric Array and Magnetic Magnetotelluric Surveys

24 Suparwoto1, Kirbani SBp.1, Ari Setiawan1, Agus Kuncaka2

1Departemen Fisika, FMIPA, UGM, Yogyakarta, 2Departemen Kimia, FMIPA, UGM,Yogyakarta

TM-02 Design of Device for Spectral Induced Polarization Laboratory Measurements in Geophysics Exploration

25 Accep Handyarso1*

and Hendra Grandis2

1Geophysics Research Group, Centre of Geological Survey, Indonesia Geological Agency, 2Applied and Exploration Geophysics Group, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung

TM-03 MT Data Smoothing in Frequency Domain Based on the B-Spline Algorithm and Qualitative Spectral Analysis

12

26 Franto1,2, Subagyo Pramumijoyo1,Lucas Donny Setijadji1

1Departement of Geological Engineering, Universitas Gadjah Mada, Yogyakarta, 2Department of Mining Engineering, Bangka Belitung University

NR-11 USING LANDSAT IMAGE 8 AND GIS FOR SURFACE MINERAL ANALYSIS IN THE SOUTHERN BANGKA

Wednesday, 22 February 2017

1 Aprillia Himatina Retnowati,Reza Fauziah

Bachelor Program of Geophysics, Padjadjaran University

NR-04 Identification of Water Spring, Water Flow Patterns and Quality Contents of Soil Water using Conductivity Measurement Direct (CMD), Geoelectricity and Coring Method, Case Study: Padjadjaran University

2 Arriqo’ Fauqi Romadlon, Sintia Windhi Niasari

Geophysics Sub-Department, Faculty of Mathematics and Natural Science, Universitas Gadjah Mada

NR-05 Identification of Geothermal system using G492D Audio Magnetotelluric Method in Mount Telomoyo Area

3 Sintia Windhi Niasari Geophysics Laboratory, Physics Department, Faculty of Mathematics and Natural Sciences, Sekip Utara, BLS 21, Yogyakarta, Indonesia

NR-07 Water Table Monitoring around the Parangwedang Geothermal Field (Indonesia) Inferred from Audio Magnetotelluric Data

4 Muhammad Yanis1, Muzakir2, Marwan2, Nazli Ismail3

1Physics Department, Syiah Kuala University; 2Department of Geophysical Engineering, Syiah Kuala University; 3Graduate Program in Disaster Science, Syiah Kuala University

EV-06 Investigation of Buried Paleochannel in Rumpet Village Eastern Banda Aceh using Electromagfnetic Induction Method

5 S. Irawan1, R. R. Aly1, R. Syahputra2, T.H.W. Kristyanto2, and A.S. Tempessy2

1Geophysics Study Program. FMIPA, Universitas Indonesia, Depok, Indonesia; 2Geology Study Program. FMIPA, Universitas Indonesia, Depok, Indonesia

EV-07 GPR Application to Investigate Soil Cracks Persistence in Cianjur Landslide

6 Shallom Samuel Harmany1, Tedy Setiawan2


EV-08 New Instrumentation Device, Based on Resistivity for Agricultural Geophysics

13

7 Muhamad Iqbal Mubarak Faharul Azman1, Azim Hilmy Mohd Yusof1, Nur Azwin Ismail1, Noer El Hidayah Ismail2

1Geophysics Department, School of Physics, 11800 Universiti Sains Malaysia, Penang, Malaysia; 2Department of Geology, Faculty of Science, Universiti of Malaya, 50603 Kuala Lumpur, Malaysia

EV-10 Slope Monitoring using 2D Resistivity Method at Sungai Batu, Pulau Pinang, Malaysia

8 Siti Nurjanah1 and Widodo2


EV-11 Innovation of Floating Time Domain Electromagnetic Method in the Case of Environmental Geophysics

9 S. Byrdina1, 2, S. Friedel3, J. Vandemeulebrouck1 , A. Budi-Santoso4 , Suhari5 , W. Suryanto5 , M.H. Rizal5 , E. Winata5 , Kusdaryanto5 , H. Grandis6

1Universite de Savoie Mont Blanc, CNRS, ISTerre, F-73376 Le Bourget du Lac, France; 2IRD, ISTerre, F-73376 Le Bourget du Lac, France; 3Comsol Multiphysics GmbH, Technoparkstrasse 1, CH-8005 Zürich; 4BPPTKG, Jl. Cendana No. 15, Yogyakarta 55166, Indonesia; 5Gadjah Mada University, Yogyakarta, 55281, Indonesia; 6Institut Teknologi Bandung, Jln. Ganesha 10, Bandung, 40132, Indonesia

TH-05 Geophysical Image of the Hydrothermal System of Merapi Volcano

10 Muhamad Afiq Saharudin, M.M Nordiana, and I.N Azwin

Geophysics Section, School of Physics, Universiti Sains Malaysia, 11800, Pulau Pinang

TH-07 Application of 2-D Resistivity Imaging and Ground Penetrating Radar (GPR) Methods in Detecting Cavities Regarding the Geohazard Assessment

11 Rifki Mega Saputra

and Widodo Geophysical Engineering, Institut Teknologi Bandung

TH-11 Identification of Near-surface Fault Structure using Radio Magnetotelluric (RMT)

12 Svetlana Byrdina1, 2, Hendra Grandis3, André Revil1, Hendra Gunawan4, and Ugan B. Saing4

1Université de Savoie Mont Blanc, Institut des Sciences de la Terre (ISTerre), Le Bourget du Lac, France; 2Institut de Recherche pour le Développement (IRD), Le Bourget du Lac, France; 3Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Indonesia; 4Center for

TH-12 Hydrothermal System of the Papandayan Volcano from Temperature, Self-Potential (SP) and Geochemical Measurements

14

Volcanology and Geological Hazard Mitigation, Indonesia

13 Nadia Amalia, M. Husaini, Ngurah Ade Kalyana, Probo Mukti Nugroho, Widodo


EG-06 Identification and Monitoring of Subsurface Structure of Tunnel using Electromagnetic Method

14 Z. M. Taqiuddin1, S. Rosli1, M. M. Nordiana1, I. N. Azwin1, S. Mokhtar2

1Geophysics Section, School of Physics, 11800 Universiti Sains Malaysia, Penang, Malaysia; 2Centre for Global Archaeological Research Malaysia, 11800 Universiti Sains Malaysia, Penang, Malaysia

EG-08 Utilizing of 2D Resistivity with Geotechnical Method for Sediment Mapping in Sungai Batu, Kedah

15 A. A. Bery1, M. M. Nordiana1, M. K. A. Nur Amalina1, Y. C. Kiu1, M. Saidin2, A. Mohammad-Afiq1, and A. M. Nur-Amalina1

1 School of Physic, Universiti Sains Malaysia, 11800 Penang, Malaysia; 2Centre for Global Archaeological Research, Universiti Sains Malaysia, 11800 Penang, Malaysia

EG-09 Subsurface Imaging using Integration of Electrical Resistivity Imaging and Geotechnical Engineering Methods in Penang, Malaysia

16 Nur Azwin Ismail1, Muhamad Iqbal Mubarak Faharul Azman1, Azim Hilmy Mohd Yusof 1, and Noer El Hidayah Ismail2

1Geophysics Section, School of Physics, Universiti Sains Malaysia, 11800 USM, Pulau Pinang, Malaysia; 2Department of Geology, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia

EG-11 Identifying Causative Factors of Mass Movements in Terengganu, Malaysia via 2-D Electrical Resistivity

17 Gesti Cita Novala*, Sudarningsih, Silvia Jannatul Fajar , Marianto, Kartika Hajar Kirana, Satria Bijaksana

Engineering Geophysics, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung

RM-05 Testing the effectivity of Magnetic Stirrer in Extraction of Magnetic Minerals from Riverine and Lacustrine Sediments

18 Aditya Pratama1, Abd. Hafidz1, Mirzam Abdurrachman2, Satria Bijaksana1

1Engineering Geophysics, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung; 2Geological Engineering, Faculty of Earth Sciences and Technology, Institut Teknologi Bandung

RM-06 Identification of Magnetic Processes using Magnetic Method and Petrogenesis Approaches in Ijen Volcanic Complex, Banyuwangi, East Java

19 Arif Wijaya, Satria Bijaksana, Silvia Jannatul Fajar


RM-07 Magnetic Characterization of Pyroclastic Density Current (PDC) of The 1257 AD Eruption of Mt. Samalas, Lombok, Indonesia:

15

Preliminary Results

20 Raghel Yunginger1, Satria Bijaksana1, Darharta Dahrin1, Siti Zulaikah2

1Engineering Geophysics, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung; 2Physics Department, Faculty of Mathematics and Natural Sciences, Malang University

RM-08 Distribution Pattern of Magnetic Minerals and Heavy Metals in Sediments from Lake Limboto, Gorontalo

21 Rizky Ramdani, Sudarningsih, Satria Bijaksana

Engineering Geophysics, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung

RM-09 Characterization of Magnetic Minerals and Heavy Metals from Sediments in Tributaries of Citarum River, West Java

22 Ida Bagus Suanadna Yogi and Widodo


TM-04 Implementation of Hybrid Optimization for Time Domain Electromagnetic 1D Inversion

23 DESMEX Team TM-06 DESMEX – Deep Electromagnetic Sounding for Mineral Exploration, Part I – Motivation & Methodology

24 R. Rochlitz, W. Mörbe, C. Nittinger, T. Martin, B. Tezkan, & DESMEX team

TM-07 DESMEX – Deep Electromagnetic Sounding for Mineral Exploration, Part II – Recent Results

25 Xiafei LYU, Chunmei DONG, and Chengyan LIN

China University of Petroleum (East China), Qingdao, China 266580

TM-08 Forward Modeling of Sedimentary Processes and Distribution of a Braided Delta System in the Xihu Depression, East China Sea

26 Andry D. Wardhana and Hendra Grandis


OG-08 Magnetotelluric (MT) Layer Stripping to Identify Sub-surface Resistivity Changes: Preliminary Results

16

Thursday, 23 February 2017

1 Mayvita Dewi1, Widodo1, Imam B Raharjo2

1 Geophysical Engineering, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung; 2PT. Pertamina Geothermal Energi

NR-09 Phase Tensor Analysis of Magnetotelluric data: Case Study of “X” Geothermal Field Data

2 Ramdani Salam1 and Rahim Achmad2

1 Faculty of Geography Universitas Gadjah Mada, Indonesia; 2Physics Dept. Of Khairun University, Indonesia

NR-10 Geothermal Potential in a Small Volcanic Island (A Study Case at Ternate Island)

3 Ramadhani Yasyfi Cysela1, Tony Rahadinata2, Asep Harja1

1Geophysics Department, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran; 2Geological Agency, Ministry of Energy and Mineral Resources of Indonesia

NR-11 Static Shift Correction of MT Data Using TDEM Data. Case Study : Geothermal area of South Sumatera

4 Edner Lumenta and Tedy Setiawan


EV-12 A Horizontal Electrical Mapping Method for Agricultural Soil Survey in West Java Area with New Instrumentation Device

5 Umi Maslinda, M.M. Nordiana, and A.A. Bery

Geophysics Section, School of Physics, Universiti Sains Malaysia

EV-14 Porosity Determination from 2-D Resistivity Method in Studying The Slope Failure

6 Rahmania and Wiwit Suryanto

Geophysics laboratory, Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Yogyakarta

EV-16 Genesis of Mujil Hill been revealed: Using Audio Magnetotelluric (AMT) profiling

7 Iqbal F. Aditama,

Widodo, Tedy Setiawan, Satria Bijaksana, Teuku A. Sanny


EV-17 Use of Electrical Geophysical Methods for Supporting Agricultural Practices

8 Iqbal F. Aditama,

Widodo, Tedy Setiawan, Satria Bijaksana, Teuku A. Sanny


EV-18 Innovation for Soil Studies with Electromagnetic Induction Techniques

9 Asep Harja, Dini Fitriani, Bambang Wijatmoko

Geophysics Department, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran

EV-19 Applied EM and Resistivity methods for near surface Investigation Arround Unpad Jatinangor

17

10 Teuku Abdullah Sanny


TH-13 Geological Control Function for Controlled Source Audio-frequency Magnetotellurics (CSAMT) Interpretation

11 Agus Laesanpura 1, Darharta Dahrin1, and Asep Sugianto2

1 Institut Teknologi bandung; 2 Geology Developmbent Center

TH-15 The AMT and Gravity Across the lithology limits in PraTertiary rock of Kebumen (Central Java)

12 Faeruz Maulana Rasyid, Widodo


TH-16 Application of Time Domain Electromagnetic Method to Study Lembang Fault, West Java

13 Rianty Kusuma Dewi, Donny Satrio Mahartha, Kevin Hartono, Lidwina, Grasiani Kristi, Widodo


TH-17 Survey the Potency of Landslides in Lembang Fault using Resistivity Tomography

14 Azizatun Azimmah and Widodo


EG-11 Detection of Underground Voids in Tahura Japan Cave Bandung using Ground Penetrating Radar

15 Apulina Priska and Wahyudi W Parnadi


EG-12 Underground Utility Mapping using Multi Frequency Ground Penetrating Radar Method in Muara Karang Power Plant, Jakarta, Indonesia

16 Mauludin Kurniawan1, Muhammad Rusli M2, Muhammad Rusydi H.2

1Tadulako Geoexploration Services, Palu, Central Sulawesi; 2Physics Departement, Faculty of Mathematics and Natural Sciences, Tadulako University

EG-14 Analysis of Earthquake-Resistant Buildings in Palu City Based on Microtremor Measurement

17 Wahyudi W Parnadi1, Rizandi G Parnadi2, and Apulina Priska1

1 Geophysical Engineering, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung; 2Department of Physics, Faculty of Mathematics & Natural Sciences, Institut Teknologi Bandung

EG-15 Detection of Underground High-Voltage Electrical Cable in Urban Area

18

18 Wahyudi W Parnadi1 and Rizandi G Parnadi2

1 Geophysical Engineering, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung; 2Department of Physics, Faculty of Mathematics & Natural Sciences, Institut Teknologi Bandung, Jalan Ganeca 10, Bandung 40132 Indonesia

EG-16 Simulation of Earthquake-Induced Landslide in West Java, Indonesia : Geometry and Its Geoelectrical Responses

19 Rosyida Azzahro, Siti Zulaikah, Markus Diantoro, Pranitha Septiana Budi

Departement of Physics, State University of Malang

RM-10 Magnetic Susceptibility and Element Composition of Mangrove Sediment in Malang, East Java Indonesia

20 Muhammad Rusli M 1,3, Subagyo Pramumijoyo1, I Wayan Warmada1, Wiwit Suryanto2

1Geogical Engineering, Gadjah Mada University; 2Geophysics, Gadjah Mada University; 3Geophysics, Tadulako University

RM-13 PALEOMAGNETISM AND GEOCHRONOLOGY OF GRANITIC ROCKS IN CENTRAL SULAWESI, INDONESIA: IMPLICATIONS FOR TECTONIC SETTING

21 Faris Sarma Putra, Fikri Zaim Karim, Denis Candra, Eleonora Agustine

Geophysical Engineering, Faculty of Mathematical and Natural Science, Universitas Padjadjaran

RM-14 The Characterization of Magnetic Soil in the Burnt Garbage Zone at Garbage Disposal Jatinangor

22 Timothy Antonio, Muhammad Khodhi Robbani, Eleonora Agustine


RM-15 Comparation high calory between low calory of coal using Suseptibility, Electric Conductivity(EC), pH (Potential of Hydrogen) parameter in Mining field Bengkulu,West Sumatera,Indonesia

23 Adinda Syifa Azhari, Eleonora Agustine, Dini Fitriani


RM-16 ANALYSIS OF POLLUTION IN AGRICULTURAL LAND POTENTIAL USING ROCK MAGNETISM METHOD

24 Ridho N. Pratama and Widodo


TM-09 Stable Iterative Methods for 1-D Joint Inversion of Radiomagnetotelluric and Transient Electromagnetic Data in Thessaloniki, Northern Greece

25 Disha Ekaputri, Sevi Maulinadya, and Hendra Grandis


TM-11 Simple Analysis for Magnetotelluric (MT) Depth Resolution using Equivalence Concept in 1D

26 Lia Maryani1, Lucki Junursyah2, Asep Harja1

1Geophysics Department, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran;

OG-09 Rotation Analysis For Magnetotelluric Data at Buton Field, Southeast Sulawesi

19

2Geological Agency

27 Fitrianita1, 3, Yunus Daud1, 2, a), Fikri Fahmi2, 3, Miman Afiff4, Yudistian Yunis4

1Department of Physics, Faculty of Mathematics and Natural Science, Universitas Indonesia 2Graduate Program of Physical Science, Universitas Indonesia 3PT NewQuest Geotechnology, Pesona Khayangan Estate DC-12 Depok, Indonesia 4PT PLN (Persero), Indonesia

TM-14 (Comparison between Magnetotelluric Short-Sounding and Full-Sounding Data During High Sunspot Activity Cycle)

20

On the new developments for the near surface

investigation using electromagnetic techniques

B. Tezkan

Institute of Geophysics and Meteorology, University of Cologne, Germany

Controlled source radiomagnetotellurics (CSRMT) and Very Low Frequency (VLF) using an unmanned aerial

system (UAS) can be considered as new and innovative methods of near surface geophysics.

Abstract. We applied the CSRMT method for the detection of a buried fault beneath a test area close to St.

Petersburg. During this survey, a rectangular current was injected into the ground using an electrical horizontal

dipole with a length of 700 m and O.5, 11.5, 30 and 105 kHz – as well as their subharmonics - were used as main

frequencies. The time series of two horizontal field components and three magnetic field components were observed

at 97 stations with a station interval of 20 m in the near, the transition, and the far field zone of the electrical dipole.

Transfer functions were derived in the frequency interval of 1 kHz to 1000 kHz from the observed electric and

magnetic time series using the newly developed processing software. They showed a smooth dependence of

frequency indicating the reliability of the observed CSRMT data. The CSRMT data were interpreted in the far field

zone by using a 2D inversion algorithm and in the near zone by using 2D forward calculations. The derived 2D

conductivity models showed clearly the location of buried faults as large resistivity contrasts. Successful VLF

measurements using an UAS could be realized successfully for the first time. Time series of the three components of

the magnetic field of VLF transmitters were observed. The UAS had a payload of 18 kg and was suitable for

geophysical measurements. A suspension system was developed enabling a stable flight of the helicopter as a

geophysical measuring platform. The optimal distance between the sensor and the helicopter was determined

through noise measurements. A low speed of 1 m/s was used during the measurements and the sensor height above

ground was approximately 3 m so that a good resolution for small-scale anomalies in the subsurface was achieved.

The developed suspension system was a first attempt to realize UAS-VLF measurements. A processing algorithm

was developed to analyze the time series of the VLF magnetic field components and to derive transfer functions

using scalar and bivariate approaches. The derived transfer functions were rotated to the strike direction of the

assumed 2D subsurface anomaly, thus enabling their quantitative interpretation by 2D inversion calculations. Two

UAS-VLF surveys were conducted over buried anthropogenic anomalies in Switzerland and over a saltwater-

freshwater transition zone in Northern Germany. Clear zero crossings of VLF transfer functions were observed on

both surveys indicating lateral inhomogeneities in the subsurface and thus proving the capability of the UAS-VLF

method to detect both the buried anthropogenic anomalies and the saltwater-freshwater transition zone. These first

applications of the UAS-VLF method in the present study show that this method can be a powerful geophysical tool

for the fast mapping of near surface subsurface.

21

Oportunity of Earth Resource Exploration using

Geophysic Method in Indonesia

Djoko Santoso

Applied and Exploration Geophysics Research Group, Faculty of Mining and Petroleum Engineering,

Institute of Technology Bandung, Indonesia

Abstract. Indonesia is country the country with large area. Compare to United State it covers from eastern to

western part of this country. Consequently, it has some significant resources such as geothermal and hydrocarbon.

Beside that in order to fulfill the need of community, a huge volume of infrastructure should be built. These

activities need support a geophysical engineering application. As an Island arc, Indonesia rich in volcano. The

number of active volcanoes are 129. The locations of geothermal potential area are distributed throughout the

country. They are 90 in Sumatra, 71 in Java, 28 in Bali and Nusatenggara, 12 in Kalimantan, 65 in Sulawesi, 30 in

Maluku, 3 in Papua. Total 299 locations. From these locations only 13336 MW had been installed until 2012 from

total potential 28617 MW. In the term of oil and gas, 16 basins are production basin, Undeveloped discovery 7,

Drilled basin with no discovery 15 and unexplored basin 22. These two areas of energy sectors, there are still big

opportunity to do an exploration work. Beside geological method, some geophysical method will play as an

important method. In relation to those two areas relatively deep target of geophysical anomalies are should be

clarify. General methods such as gravity, magnetic and electric are widely used. On the other electromagnetic

method also has been used to support better subsurface determination. Current Infrastructure development in

Indonesia also a promising activities in the future. According to infrastructure development plan of Government

Indonesia until 2019 the cost is approximately 5.5 trillion rupiahs. It will cover by National Government budget

40%, State Enterprises 20%, Private Enterprises 30% and Local Government 10%. The activities are including road

and bridges, railways, sea infrastructure, air infrastructure, river transportation and it cross transportation, city

transportation, information and telecommunication, water resources and housing. Most of these activities are related

to underground condition, such as foundation of any kind infrastructures, ground water location, etc. Therefore the

application of geophysical method will be promising in the future Indonesia development.

22

“All charged up": Advances and applications for induced

polarization surveys

Douglas W. Oldenburg and Seogi Kang

Geophysical Inversion Facility, UBC, Canada

Abstract. Induced polarization (IP) surveys have been an important for mineral exploration and are continuing to

find new applications in permafrost, ground water studies, and some environmental contaminant problems. In a

traditional IP survey a DC current is input to the ground and voltages, measured during an off-time, indicate

chargeability. This talk focuses on two advancements that have arisen over the last decade that allow us to extract

more information about the chargeable earth. The first is the ability to sample the voltage waveform at a high

sampling rate. Voltages at early times after shut-off are generally heavily affected with EM induction signals and

these are traditionally thrown away. However, we show how these early time data can be inverted to yield

information about the background conductivity. In a subsequent process, at later times where chargeability is

important, we use this conductivity to remove the contaminating EM induction effects. This enhances the time range

over which IP signals are available and thereby makes them more useful in detection and discrimination problems. A

second advance is the application of IP surveys that use inductive transmitters. Although the same physical

principles apply as in the traditional grounded DC/IP survey, the charging process is never allowed to achieve a

steady state. This complicates the analysis. We outline a general procedure to overcome the hurdles and apply the

technique to an airborne time domain EM survey over a kimberlite pipe in Canada. The same analysis has

applications for permafrost studies and near-surface geologic mapping.

23

Rock Magnetic Methods and Their Application in

Environmental Studies

Satria Bijaksana

Global Geophysics Research Group, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung

corresponding author’s email : [email protected]

Abstract. Since the mid-80s, the roles of rock magnetism have evolved from supporting paleomagnetism to versatile

tools in varios applications from environmental studies, paleoclimate reconstruction to to exploration of minerals and

hydrocarbon. Such evolution provides ample opportunities to scientists and engineers working in environmental

issues not only use new methods but also to develop new magnetic methods and approaches that are more

appropriate for environmental studies. In this presentation, I will introduce methods in rock magnetism that are

routinely used in environmental studies. Examples of case studies in Indonesia will be presented, in particular

paleoclimatic reconstruction using lacustrine sediment from Lake Towuti in South Sulawesi, characterization of

landfill leachate and pollution monitoring in river sediments.

24

Three-dimensional Magnetotelluric Inversion

Weerachai Siripunvaraporn

Department of Physics, Faculty of Science, Mahidol University, Rama 6 Rd., Rachatawee, Bangkok 10400,

THAILAND.

Abstract. Recently, the three-dimensional (3-D) magnetotelluric (MT) survey has become the standard practices for

many applications. This is due largely to the availability of the 3-D MT inversion codes in the market, such as

WSINV3DMT and MOD3DEM and many others. As we all know that the Earth is really 3-D, there are several pros

to do the 3-D MT survey. However, there are also several drawbacks particularly if ones do not understand how the

3-D MT inversion works, the results can be misleading. Both pros and cons will be greatly mentioned in this

presentation. In addition, the techniques behind the 3-D MT inversion, such as the Occam’s inversion both model

space and data space methods, the Gauss-Newton, the Gauss-Newton with the conjugate gradient, the quasi-Newton

and the non-linear conjugate gradient methods, will be summarized. In addition to the main driven mechanisms,

other necessary components such as the forward modeling, the sensitivity calculations, model covariance, and the

parallel implementation will also be reviewed.

25

Advances in Marine Controlled-Source Electromagnetic

Research

Yuguo Li

College of Marine Geosciences, Ocean University of China, Qingdao, China

Key Lab of Submarine Geosciences and Prospecting Techniques of Ministry of Education

Abstract. This presentation will report on advances in marine controlled-source electromagnetic (MCSEM) research

at the Marine EM laboratory at Ocean University of China. The marine controlled-source electromagnetic method

(CSEM) has emerged as a useful exploration technique for mapping offshore hydrocarbon reservoirs and

characterizing gas hydrates bearing in shallow sediments. In a marine CSEM survey, a horizontal electric dipole

source (HED) generally is towed at a height of a few tens of meters above the seafloor. The HED source transmits

low frequency electromagnetic signals to an array of ocean bottom electromagnetic (OBEM) receivers, which

detect and record the electromagnetic signals from the source. The resistivity distribution below the seabed may be

determined by interpreting the recorded electromagnetic fields. A new type of broadband Ocean-Bottom

ElectroMagnetic (OBEM) receiver has been recently developed at OUC. The OBEM receiver is an autonomous

seafloor data logging system and is designed to measure both the magnetotelluric signal and the controlled-source

electromagnetic signal on the seafloor. The OBEM receiver collects three components of the electrical field and two

horizontal components of the magnetic field. A high dynamic range, high gain amplifier unit and a high precision

clock unit, specially designed for detecting weak signals, were added to the 6 channel, 24-bit data logger. A pair of

the low noise silver-silver chloride electrodes measure the electric field at the end of 10 meter long dipole and the

magnetic fields are measured by using the induction coil magnetometers. A CTD unit with the compact compass is

mounted on the top of the non-magnetic frame. Our receiver is capable of resisting water pressure to depth of 4000

meters. These seafloor electromagnetic receivers concluded their 1000- and 4000-meter deep sea trials in the South

China Sea last year, marking great progress in its initial stage in the development of marine electromagnetic

instruments and techniques. We have seen more than 40 deployments with 100% recovery rate. We also have

developed a new transmitter for the marine CSEM sounding. The transmitter can deliver up to 1000A current into a

neutrally buoyant antenna of 200m long. It was deep-towed at the end of a cable containing three optical fibers that

is used to power the transmitter and for telemetry between the deep-towed transmitter and the shipboard control

console. It hosts an altimeter to measure height above the seafloor and an ultra-short baseline acoustic transponder to

locate the position of the transmitter. It also hosts a CTDV (conductivity, temperature, depth and sound velocity)

sensor to measure the seawater conductivity and velocity. The transmitter has been successfully tested in the Yellow

Sea and in the Southern China Sea. In this presentation, we will report on field results collected using our transmitter

and OBEM receivers.

26

The Differential Electric Dipole: A New Marine Time-

Domain Electromagnetic Method to Study the Shallow

Sub-Seafloor Resistivity Structure in Coastal Regions

Amir Haroon1, a)

and Bülent Tezkan1, b)

1 Institute of Geophysics and Meteorology, University of Cologne, Germany

a)

[email protected] b)

[email protected]

Abstract. To study the near-surface resistivity structure within shallow marine environments, a new time-domain

electromagnetic method called Differential Electrical Dipole (DED) was developed at the Institute of Geophysics

and Meteorology, University of Cologne. The DED transmitter consists of two horizontal electric dipoles that share a

common central electrode. Thereby, the central electrode has one polarity while the two outer electrodes have the

other polarity, so that the current in each dipole flows in opposite directions. In theory, the excited EM field of DED

is more sensitive towards lateral resistivity discontinuities with the drawback of weaker signal strength in

comparison to the conventional time-domain CSEM systems. Preliminary 1D and 2D modelling studies compare the

novel DED method to the conventional marine time-domain CSEM method, sometimes also referred to as the

marine Long Offset Transient Electromagnetic (LOTEM). The results show that for the given resistivity structure, it

is advisable to apply a step-on current excitation to delineate the depth of the resistive freshwater aquifer more

precisely. Furthermore, the studies indicate that a multi-dimensional interpretation scheme is needed to adequately

assess measured DED data in coastal regions due to the effect of bathymetry on the measured data. A first DED

application was realised in April 2016 in the coastal region of Bat Yam, Israel to study the seaward extent of a

freshwater aquifer underneath the Mediterranean Sea. The application proved the feasibility of marine DED in

shallow marine environments and, additionally, detected the seaward extent of the resistive sub-seafloor freshwater

body. Based on the measured step-on data, the freshwater/seawater interface at the western aquifer boundary was

precisely determined using a 1D inversion and subsequent 2D modelling approach. Moreover, the data allowed a

preliminary delineation of the resistivity structure at the western aquifer boundary.

27

A new array system for Multiphysics (MT, Lotem &

microseismics) with focus on reservoir monitoring

K. Strack, S. Davydycheva, T. Hanstein and M. Smirnov

KMS Technologies (Thailand, USA & Germany)


Abstract. Over the last 6 years we developed an array system for electromagnetic acquisistion (magnetotelluric &

Lotem) that includes microseismic acquisition. While the system is being used in many countries for

magnetotellurics, we focus here on the autonomous operation as reservoir monitoring system including a shallow

borehole receiver and 100/150 KVA transmitter. Marine extension are also under development. For Enhanced Oil

recovery, in addition to reservoir flood front movements, reservoir seal integrity has become an issue (Carlson,

2013). Seal integrity is best addressed with microseismics while the water flood front is best addressed with

electromagnetics. Since the flooded reservoir is conductive and the hydrocarbon saturated part is resistive, you need

both magnetic and electric fields. The fluid imaging is addressed using electromagnetics, and after careful 3D

feasibility and noise tests, we selected Controlled Source Electromagnetics (CSEM) in the time domain as the most

sensitive method (Strack and Aziz, 2013; Kumar and Hoversten, 2012). From the 3D modeling we derived a key

requirement that borehole and surface data needed to be integrated by measuring between surface to borehole and

also calibrated using conventional logs including anisotropy. This would significantly reduce the risk (He et al., 2006

and 2010; Tietze et al., 2015). To overcome the volume focus inherent to electromagnetics we added a new

methodology to focus the sensitivity under the receiver. The same can be achieved using a shallow borehole system

that includes microseismic, 3C magnetics and 3C electrical measurements. Field data and 3D modeling confirm this

and as results this could increase the efficiency of applying Lotem to exploration and reservoir monitoring problems.

28

Code Paper Title

TM-01 Magnetotelluric Array andMagnetic Magnetotelluric Surveys

TM-02 Design of device for Spectral Induced Polarization Laboratory

measurements in Geophysics Exploration

TM-03 Magnetotelluric (MT) Data Smoothing based on B-Spline Algorithm and

Qualitative Spectral Analysis

TM-04 Implementation of Hybrid Optimization for Time Domain

Electromagnetic 1D Inversion

TM-05 Time Domain Electromagnetic 1D Inversion Using Genetic Algorithm

and Particle Swarm Optimization

TM-06 DESMEX – Deep Electromagnetic Soundings for Mineral Exploration,

Part I – Motivation & Methodology

TM-07 DESMEX – Deep Electromagnetic Soundings for Mineral Exploration,

Part II – Recent Results

TM-08 Forward Modeling of Sedimentary Processes and Distribution of a

Braided Delta System in the Xihu Depression, East China Sea

TM-09 Single and Sequential Inversion of Radiomagnetotelluric and Transient

Electromagnetic Data

TM-10 Two-Dimensional Inversion Finite Element Modeling of Magnetotelluric

Data at “J” Geothermal Area, Indonesia

TM-11 Simple Analysis for Magnetotelluric (MT) Depth Resolution using

Equivalence Concept in 1D

TM-12 Resistivity and Gravity Data for Aquifer Modelling in Kendari (South

Sulawesi)

TM-13 Numerical Techniques for Solving Gauss Quadrature Semi-infinite

Integral used in Vertical Magnetic Dipole Forward Modeling

TM-14 Comparison between Magnetotelluric Short-Sounding and Full-Sounding

Data During High Sunspot Activity Cycle

TM-06

TM-01

29

Magnetotelluric Array and Magnetic Magnetotelluric

Surveys

Dr. Wen J Whan

3JTech

Abstract. Surveys using synchronous MT array could further reduce the local noise. Multi variance

analysis(Egbertand Booker)transformsthe array data into two large eigenvalue, which corresponding to nearly

uniform source fieldsand comes out with a multivariate transfer function.Synchronous MT array at three or more

sites ensure removal of galvanic distortions in MT apparent resistivity curves (V. Plotkin). In 2012, we patented an

EM and its Combined Surveying Apparatus and Method. On the method, we proposed a magnetic MT (MMT)

survey, where the electric field is calculated by the change of vertical magnetic field. The method would be

convenient for area where the reasonable spacingfor electrodes isdifficult to be located. Figure above represents the

notations for calculating the electrical field from the vertical component of electromagnetic field. From Maxwell

Equations, we get

∮ E．dx = -dΦn,s / dt (2)

Equation (2) states that the sum of the electrical field along a closed path equals to the negative change rate of the

vertical components of the magnetic flux through the surface enclosed by the closed path. Assuming Ei,jis the

circular electrical field on the Cell[I,j] and BZi,jis the vertical component of the magnetic field through the cell, also

assuming the cell size is small enough so that both Ei,jand BZi,jare uniform, we get

Ei,j= -(dl * dBZi,j/ dt ) / 4 (3)

where dl is the distance between the grids. The X component of the electrical field is then EXi,j= Ei,j-Ei,j-1, while the

Y component of the electrical field is EYi,j= Ei-1,j-Ei,j. 3JTech and National Taiwan Ocean University (NTOU)has

carried out a MT array survey in south I-Lan,Taiwan. There are 10 arrays. Each array has 8 stations and one remote

reference. Between each adjacent array, there are two overlapped stations. The data will beusedfor array processing

and MMT verification.

Design of device for Spectral Induced Polarization

Laboratory measurements in Geophysics Exploration

Suparwoto1, Kirbani SBp.

1, Ari Setiawan

1, Agus Kuncaka

2

1Departemen Fisika, FMIPA, UGM, Yogyakarta

2Departemen Kimia, FMIPA, UGM,Yogyakarta

Abstract. Laboratory experiments to study the induced polarization (IP) phenomenon on natural and artificial

samples are of great importance as they can explain on the cause and nature of the phenomenon. IP method has been

the most succesful in mining exploration, particularly in the search for metal oxide and sulphide mineralizations.

The Spectral Induced Polarization or Complex Impedance Method is essentially a multi-frequency version of IP. The

basic techniques for measuring complex impedance are amplitude voltage measurement, current measurement and

phase difference detection between voltage and current as function of frequency. The device consist of two main

part, the transmitter and receiver. Transmitter transmits sinus wave current with frequency varied automatically

from 0,1 Hz to 1000 Hz. In order to improve the accuracy of the device, the high impedance differential

instrumentation amplifier are used in the receiver. The outputs from voltage amplifier and current amplifier are sent

to data logger. Experimental measurement on RC circuits were carried out to prelimininary evaluate the performance

of the device. Different type of ore bodies can be distinguished based on typical shapes of their spectral IP

responses.The result obtained by the device were found to be in good agreement with the teoretical computation

obtained on RC circuits. Overall mean error of 1 % in magnitude and 0,2o in phase over frequency range of 0,1 Hz

to 1000 Hz. The largest error in phase measurement occured at low frequency below 1 Hz.

TM-02

TM-01

30

Magnetotelluric (MT) Data Smoothing based on B-Spline

Algorithm and Qualitative Spectral Analysis

Accep Handyarso1, a)

and Hendra Grandis2, b)

1Geophysics Research Group, Centre of Geological Survey, Indonesia Geological Agency.

Building B 1st Floor, Jalan Diponegoro no. 57, Bandung 40122, Indonesia. 2Applied and Exploration Geophysics Group, Faculty of Mining and Petroleoum Engineering, Institut Teknologi

Bandung (ITB). Basic Science Centre B 2nd

Floor. Jalan Ganesha 10, Bandung 40132, Indonesia.

a)

Corresponding author: [email protected]; b)

[email protected]

Abstract. Data processing is one of the essential steps to obtain optimum response function of the Earth's

subsurface. The MT Data processing is based on the Fast Fourier Transform (FFT) algorithm which converts the

time series data into its frequency domain counterpart. The FFT combined with statistical algorithm constitute the

robust processing algorithm implemented in the proprietary SSMT2000 software. The robust processing has three

variants, i.e. No Weight (NW), Rho Variance (RV), and Ordinary Coherency (OC). The RV and OC options allow

for denoising the data but in many cases the robust processing still results in not so smooth sounding curve, such that

the XPR (crosspower) analysis must be conducted during the data processing. The XPR analysis or selection is done

using the MT-Editor software and this step is very time consuming. The collaboration of B-Spline algorithm and

Qualitative Spectral Analysis in the frequency domain could be of advantages during these steps. The technique is

started by using the best coherency from the robust processing results. In the Qualitative Spectral Analysis we

determine which part of the data within each frequency that is more or less reliable, then the next process invokes B-

Spline algorithm for data smoothing. This algorithm would select the best fit of the data trend in the frequency

domain. The smooth apparent resistivity and phase sounding curves can be considered as more appropriate to

represent the subsurface. This algorithm has been applied to the real MT data from several survey and give

satisfactory results.

Implementation of Hybrid Optimization for Time Domain

Electromagnetic 1D Inversion

Ida Bagus Suanadna Yogi and Widodo

Institut Teknologi Bandung

Corresponding author: [email protected]

[email protected]

Abstract. Time domain electromagnetic (TDEM) is one of non-invasive geophysical methods. This method is an

active method that applied the electromagnetic wave properties so that the conductivity of the lithology in the

subsurface can be measured. Inversion of TDEM data was usually calculated using derivative of least square

method, such as Levenberg-Marquardt and Occam algorithms. These methods have drawbacks, such as the results

are very depend on good starting models, and the final results sometimes is local minimum, instead of global

minimum. These drawbacks can be overcome by using global optimization approach, such as Monte Carlo,

simulated annealing, and genetic algorithm. However, these global optimization methods need long calculation time.

Because of that, this research try to combine these two approach as hybrid optimization method. The hybrid

optimization method is combination of conjugate gradient (CG) method and very fast simulated annealing (VFSA)

method. The algorithm was applied to inverted several synthetic models of TDEM data. The synthetic data was

added with noise to test the capabilities of hybrid optimization algorithm. This combination method was the most

efficient method when compared to the conjugate gradient or simulated annealing method separately. Levenberg-

Marquardt and genetic algorithm inversion results of Volvi Basins TDEM data were compared with the hybrid

optimization algorithm results. The hybrid optimization results were better than Levenberg-Marquardt results, and

when compared to the genetic algorithm processes, the calculation times were faster.

TM-03

TM-04

mailto:[email protected]

31

Time Domain Electromagnetic 1D Inversion Using

Genetic Algorithm and Particle Swarm Optimization

Ida Bagus Suananda Yogi and Widodo



[email protected]

Abstract. Most of geophysical data needs to be inverted, so that the inversion results can be interpreted further.

There are two mayor methods to approach inversion calculation, they are least square methods with its derivative,

and global optimization methods. The global optimization methods have two advantages over least square methods

and its derivative; the inversion result are not sensitive to the starting model and this method can get results from

global minimum instead of local minimum. These advantages make the global optimization methods give better

results when priori data is unavailable. In this research we tried to implement genetic algorithm (GA) and particle

swarm optimization (PSO) to do inversion of time domain electromagnetic (TDEM) 1D data with central loop

configuration. The inversions were applied for synthetic models with and without noise addition. The starting

models were varied from the closest to the furthest from the real synthetic models. With the same starting models,

the Levenberg-Marquardt algorithm was applied and compared to see the significance of starting models

determination. After that, the results and the processes from the two global optimization methods were compared.

This comparison results showed that the results and the performance were not much different. Both inversion results

give similar models with the synthetic models. At the end of the research, the global optimizations methods were

applied to TDEM real data from Volvi Basin, Greece.

DESMEX – Deep Electromagnetic Soundings for Mineral

Exploration, Part I – Motivation & Methodology

Authors Part I: DESMEX team

Abstract. The interdisciplinary research project DESMEX (Deep Electromagnetic Soundings for Mineral

Exploration) is focused on various electromagnetic methods, instrumental design, petrophysics, mineralogy and

geochemistry. It particularly aims to identify deep mineral deposits up to 1 km depth. The main goal is to establish a

new semi-airborne mineral exploration system using highly-sensitive airborne magnetic field sensors and powerful

ground-based electric dipole transmitters. The semi-airborne experiment is supported by ERT (Electrical Resistivity

Tomography) and LOTEM (Long Offset Transient ElectroMagnetics) measurements as well as modeling studies and

laboratory investigations of rock samples. In the first part (I – Motivation & Methodology), we introduce the

DESMEX objectives related to the survey area, which is a former Antimonite deposit near Schleiz, Germany.

Furthermore, an overview of the involved universities, research institutes and companies is given. In this context, the

individual methods and competences of all project-partners and their impact on the study objectives are presented. In

particular, both, a new coil and LT (Low Temperature) SQUID based helicopter receiver system, have been

developed by Metronix and IPHT/Supracon for most accurate magnetic field records with respect to impulse or step

response measurements, respectively. The semi-airborne survey design is developed by University of Muenster and

the flight tests are conducted in cooperation with BGR. High-current source signals for an optimum signal-to-noise

ratio can be generated by two different transmitters, which are also utilized for the large-scale ERT and LOTEM

support surveys by University of Cologne and LIAG. Finally, BGR and Freiberg University of Mining and

Technology use various laboratory methods such as SIP for detailed rock characterization.

TM-05

TM-06

https://en.wikipedia.org/wiki/Freiberg_University_of_Mining_and_Technology



32

DESMEX – Deep Electromagnetic Soundings for Mineral

Exploration, Part II – Recent Results

Authors Part II: R. Rochlitz, W. Mörbe, C. Nittinger, T. Martin, B. Tezkan, &

DESMEX team

Abstract. The interdisciplinary research project DESMEX (Deep Electromagnetic Soundings for Mineral

Exploration) is focused on various electromagnetic methods, instrumental design, petrophysics, mineralogy and

geochemistry. It particularly aims to identify deep mineral deposits up to 1 km depth. The main goal is to establish a

new semi-airborne spatial resolution is worse. Finally, first data examples of flight tests with the newly developed

airborne receiver systems using a ground-based dipole source are presented. The geophysical data gathered in the

area of investigation are jointly analyzed as basis for the semi-airborne survey design. Furthermore, these data are

the reference for the novel semi-airborne system, whose main application is planned in summer 2017.

Forward Modeling of Sedimentary Processes and

Distribution of a Braided Delta System in the Xihu

Depression, East China Sea

Xiafei LYUa), Chunmei DONG

b) and Chengyan LIN

China University of Petroleum (East China), Qingdao, China 266580

a)

Corresponding author: [email protected] b)

[email protected]

Abstract. The Xihu Depression, located in the East China Sea, is a promising yet challenging deep water low-

permeability frontier with abundant gas potential. The target Oligocene Huagang Formation comprises massive braid

delta deposit, but its source locations and sedimentary patterns are not well constrained. We proposed a

comprehensive numerical modeling workflow to reconstruct the reservoir distribution within the Xihu Depression.

Based on detailed analyses of seismic, well logs, core data and modern analogs, we documented the controlling

factors for sedimentary processes and their spatial and temporal deposition patterns. Good reservoir sand is modeled

to have deposited on both slopes and depression floor due to a combination of slope angles, hydrodynamics of river

flow and waves. Sedimentary patterns differ on flanks. The result shows that sand was deposited along the northwest

slope continuously. However, large volume of sand dispersed on the southeast slope since this slope is steeper and

water is rather shallow; sand displayed discontinuity and spread to the center of the depression floor. Silt contributed

little to the whole stratigraphy and accumulated mostly on the periphery of sand deposit. Shale was distributed

primarily in the center of the depression. The modeling result confirms that sediment was derived from both

southeast and northwest source areas. This conclusion is also proved by core observation results. The result also

supports that sediment in the center of the depression sharing mixed sources. This study combines established

knowledge and leading-edge forward modeling technique to document a braided delta system for a thorough

assessment of sedimentary processes and distribution in an emerging deep water frontier, which tailors our

understanding on the braided delta depositional model of the Huagang Formation in the Xihu Depression. It is found

that the workflow offers a fresh perspective to delineate reservoir distribution for future drilling in exploration

frontier.

TM-07

TM-08

33

Single and Sequential Inversion of Radiomagnetotelluric

and Transient Electromagnetic Data

Ridho N. Pratama1 and Widodo

2

1Undergraduate Program of Geophysical Engineering, Institut Teknologi Bandung,

2Lecturer of Geophysical Engineering, Institut Teknologi Bandung.


[email protected]

Abstract. The Volvi basin is an alluvial valley located 45 km northeast of the city of Thessaloniki in Northern

Greece. It is a neotectonic graben (6 km wide) structure with increasing seismic activity where the large 1978

Thessaloniki earthquake occurred. Hence, near surface Electromagnetic (EM) which are Radiomagnetotelluric

(RMT) and Transient Electromagnetic (TEM) measurements are carried out to understand the location of the local

active fault and the top of the basement structure of the research area. The sequential Inversion of both data was

performed to get detailed information of subsurface structure. Whereas RMT data is sensitive to describe in the

shallow structure, while the deeper structure is related to TEM data. We derived the sequential inversion scheme

from the second order of Marquardt algorithm using singular value decomposition (SVD). The sequential model has

been improved the resolution of the single model which has more than 0.9 on the importance value. Single and

sequential inversions of RMT and TEM give a consistent result in which both identify the fault structure indication.

Two-Dimensional Inversion Finite Element Modeling of

Magnetotelluric Data at “J” Geothermal Area, Indonesia

Agus Setyawan1, a)

, Nur Rachmaningtias2, b)

and Imam Baru Raharjo3, c)

1 Department of Physics, Faculty of Science and Mathematics, Diponegoro University, Tembalang, Semarang,

Indonesia, 50275 2 Undergraduate Student of Department of Physics, Faculty of Science and Mathematics, Diponegoro

University, Tembalang, Semarang, Indonesia, 50275 3 PT.Pertamina Geothermal Energy,Menara Cakrawala fl.15

th, MH.Thamrin , Jakarta, Indonesia, 10340

a)Corresponding author: [email protected]

b)[email protected]

c)[email protected]

Abstract. Two-dimensional resistivity analysis of magnetotelluric data has been done at “J” geothermal area which

is located in southern part of Indonesia. The objective is to understand subsurface structure beneath reasearch area

based on 2-D modeling of magnetotelluric data. The inversion finite element method were used for numerical

simulations which requires discretization on the boundary of the modeling domain. The modeling results of

magnetotelluric data shows relativity structure dissemination: 0-10 ohm.m in a thickness of 1 km (Clay Cap), 10-100

ohm.m with 1-2 km depth respectively (reservoir zone), and on a scale of 100-1000 ohm.m in a depth of 2-3 km

(heat source zone). The result of relativity structure can be used to delineate an area with geothermal prospect around

12 km2 moreover the geothermal potency is up to 96 Mwe.

TM-10

TM-09


34

Simple Analysis for Magnetotelluric (MT) Depth

Resolution using Equivalence Concept in 1D

Disha Ekaputri1, Sevi Maulinadya

1 and Hendra Grandis

1, 2

1Geophysical Engineering Program, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung

2Applied and Exploration Geophysics Research Group, Faculty of Mining and Petroleum Engineering,



Abstract. The magnetotelluric (MT) method is capable of providing an estimate of the earth's resistivity variation up

to a relatively great depth depending on the frequency (or period) of the recorded electromagnetic (EM) fields. The

MT investigation depth is well-known and expressed by the skin depth formula, although it is only a rough

approximation derived for a homogeneous medium. On the other hand, MT resolution in depth is much more

complex even for a simple medium, e.g. 1D. It is widely accepted that MT resolution is decreased with depth due to

diffusive character of the EM fields. We tried to investigate the resolving capability of MT by using a simple

synthetic 1D model where a thin conductive layer is embedded in a homogeneous more resistive medium. In such a

case, we consider that the second thin layer can be resolved only if it has a conductance (conductivity-thickness

product) at least the same as the overburden layer. For an overburden with a higher resistivity, a deeper thin layer

can be resolved, which in accord with the skin depth principle. Within the equivalence concept, a very much thinner

layer can produce the same conductance with the similar model response, i.e. can be resolved. However, such

situation is less likely from the commonly accepted practical point of view. Although we cannot formally formulate

the lower thickness threshold, this exercise can exemplify the limitation of MT method in resolving a thin layer at

depth. In Indonesia, there are studies using MT with results beyond its real capability, i.e. models with a very thin

layer at depth from unconstrained inversion. A deeper comprehension on the fundamental concept of the method and

on inversion modeling is needed to avoid such misconduct.

Resistivity and Gravity Data for Aquifer Modelling in

Kendari (South Sulawesi)

Agus Laesanpura and Warsa



Abstract. Kendari is a town in south east Sulawesi (Celebes) where the old rock of Triassic age is superposed with

younger rock as unconformable. The emerging people and development infrastructure, is demanding the available

water for domestic needs, not only from the river but also the groundwater. The water basin and its aquifer is

investigate by resistivity and gravimeter. The resistivity-IP imaging of Wenner-Schlumberger configuration in

several section, and the Wenner sounding in several site is also executed. The deepest part of basin is delineated by

gravity data. Besides the geophysics data, the cropouts of significance rock is also observed. Several section show

the the resistivity result in near surface is agree well with crop out observation, such as conglomeratic rock and the

resistivity signal of low velocity layer. The oldest rock crop out in surface is also agree well with the high resistivity

value. The IP data to determine the water contents inside the rock in aquifer layer is also show up, and agree with the

water availability. The prediction of groundwater basin could be detected by several mGal of gravity value. As

result, we could draw the conceptual model of groundwater basin and hydrology aquifer.

TM-11

TM-12

35

Numerical Techniques for Solving Gauss Quadrature

Semi-infinite Integral used in Vertical Magnetic Dipole

Forward Modeling

Wahyu Srigutomo and Ariel A. Rahardi

Physics of Earth and Complex Systems, Faculty of Mathematics and Natural Sciences, Institut Teknologi

Bandung, Jl. Ganesa 10 Bandung, Indonesia 40132

[email protected]

Abstract. Forward modeling of time domain electromagnetic responses including the vertical magnetic dipole

configuration involves calculation of semi-infinite integral used in transformation of response from frequency

domain into time domain. The realization of the Gauss quadrature integration was implemented by four different

techniques: Gauss-Legendre, Gauss-Laguerre, Gauss-Lobatto and Gauss-Kronrod. In this study, comparison of these

four techniques for a homogeneous half-space and a horizontally layered Earth showed that the Gauss-Legendre

technique yielded better accuracy to the analytical responses.

Comparison between Magnetotelluric Short-Sounding and

Full-Sounding Data During High Sunspot Activity Cycle

Fitrianita1, 3

, Yunus Daud1, 2, a)

, Fikri Fahmi2, 3

, Miman Afiff4, Yudistian Yunis

4

1Geothermal Laboratory, Department of Physics, Faculty of Mathematics and Natural Science, Universitas

Indonesia, Depok, Indonesia 2Master Program in Geothermal Exploration, Graduate Program of Physical Science, Universitas Indonesia,

Jakarta, Indonesia 3PT NewQuest Geotechnology, Pesona Khayangan Estate DC-12 Depok, Indonesia

4PT PLN (Persero), Indonesia

a)


Abstract. The maximum sunspot cycle that occurs every 11 years reached peak in 2014 and the next peak is

predicted will be occurred in 2025. High sunspot activity causes increasing of earth's magnetic field intensity so it

can affect the magnetotelluric (MT) measurement result. Fifteen to seventeen hour magnetotelluric sounding had

been done in Ulumbu Geothermal Field (Flores) in year of 2015 obtained high coherency value, reaching 60-90%.

The high coherence value that successfully obtained especially for the data in lower frequency (0,01 – 0,1 Hz),

become the basis to study the possibility of conducting MT measurement with shorter duration. In this research, we

tried to cut the duration of magnetotelluric acquisition becoming 3-5 hours. MT curve from minimum 3 hours short

sounding measurement showed a smooth and similar trend with the full sounding result (15-17 hours) mainly when

the coherence value is more than 60%. Results of the 3-D MT data inversion for the short sounding and full

sounding measurements also showed the similarity in delineating the subsurface structure of geothermal system.

Therefore, short time sounding of MT data acquisition (with minimum duration of 3 hours) is possible to be done

when the sunspot activity is maximum. Short time sounding of the MT data acquisition can reduce the cost of MT

survey and increase the effectiveness of the MT result.

TM-13

TM-14


36

Code Paper Title

OG-01 Uses of Lotem for Indonesian hydrocarbon applications

OG-02 An Application of LOTEM around Salt Dome near Houston, Texas

OG-03 Identification of Pre-Tertiary Deposit by Using Magnetotelluric Method

in Bintuni Basin, West Papua, Indonesia

OG-04 Application of TEM technique in South-East Asia

OG-05 Formation Factor Calculation of Digital Rock Images with the Help of

FEM

OG-06 Reservoir Identification using Short Offset Transient Electromagnetic

Method

OG-07 Non-linear Inversion Modeling of TDEM Data for Reservoir

Characterization

OG-08 Magnetotelluric (MT) Layer Stripping to Identify Sub-surface Resistivity

Changes: Preliminary Results

OG-09 Rotation Analysis For Magnetotelluric Data at Buton Field, Southeast

Sulawesi

OG-03

OG-08

37

Uses of Lotem for Indonesian hydrocarbon applications

R. Aftartu1, S. Davydycheva

2 and K. Strack

2

1Sucofindo, Jakarta

2KMS Technologies (Thailand, USA & Germany)


Abstract. While magnetotellurics has been used extensively in Indonesia, the percentage of good quality data is

limited due to the high population density and often the geologic condition. We are investigating to apply controlled

source EM in the time domain (sometimes also known as Lotem) because it overcomes the noise issue by using a

high power transmitter. Among the many applications for Indonesia we have selected sub-basalt and porosity

mapping in carbonates because we can demonstrate the benefit of the technology with succeful Lotem case histories

of the past and illustrate the new use with 3D modeling. Sub-basalt exploration is hindered by either diffuse

reflection of the seismic wave or high seismic velocities. EM sees transparently through them. Target are resistive

(hydrocarbon) and conductive (sediments). We are illustrating the succes of Lotem with results from Europe and

India for similar situations including joint inversion with magnetotellurics. Carbonate porosity mapping is also

difficult for seismic due to the high velocities and the low acoustic velocity contrats between oil and brine. The later

shows an excellent resistivity contrast and since the section is resistive it is also an ideal Lotem target. Over the past

few decades there have been similar applications in Australia and Europe which at that time appeared challenging

but in today world with more successes in Em make complete sense. We also illustrate the use of improved focusing

for a case history in PNG where we are able to avoid the influence of near surface carsting.

An Application of LOTEM around Salt Dome near

Houston, Texas

Andri Yadi Paembonan1, c)

, Rungroj Ajdwech1, b)

, Sonya Davydycheva3, d)

,

Maxim Smirnov2, 3, e)

, and Kurt M. Strack3, a)

1Master Program of Getechnology, Khon Kaen University

2Department of Civil, Environmental and Natural Resources Engineering Geothermal Engineering,

Luleå University of Technology 3KMS Technologies.

a)


Corresponding author: [email protected] c)

[email protected] d)

[email protected] e)

[email protected]

Abstract. A salt dome is an important large geologic structure for hydrocarbon exploration. It may seal a porous

reservoir of rocks that form petroleum reservoirs. Several techniques such as seismic, gravity, and electromagnetic

including magnetotelluric have successfully yielded salt dome interpretation. Seismic has difficulties seeing through

the salt because the seismic energy gets trapped by the salt due to it high velocity in salt. Gravity and

electromagnetics are more ideal methods. Long Offset Transient Electromagnetic (LOTEM) and Focused Source

Electromagnetic (FSEM) were tested over a salt dome near Houston, Texas. LOTEM data were recorded at several

stations with varying offset, and the FSEM tests were also made at some receiver locations near a suspected salt

overhang. The data were processed using KMS’s processing software: First, for assurance, including calibration and

header checking; then transmitter and receiver data are merged and microseismic data is separated; Finally, data

analysis and processing follows. LOTEM processing leads to inversion or in the FSEM case 3D modeling. Various

3D models verify the sensitivity under the salt dome. In addition, the processing was conducted pre-stack, stack, and

post-stack. After pre-stacking, the noise was reduced but it showed the ringing effect due to a low-pass filter.

Stacking and post-stacking with applying recursive average could reduce the Gibbs effect and produce smooth data.

OG-01

OG-02

38

Identification of Pre-Tertiary Deposit by Using

Magnetotelluric Method in Bintuni Basin, West Papua,

Indonesia

Hidayata), Asep Rohiman

b), and Saultan Pandjaitan

Center of Geological Survey, Geological Agency, Ministry of Energy and Mineral Resources Republic

Indonesia

a)


[email protected]

Abstract. Bintuni Basin is categorized as a Paleogene Passive Margin-Neogene Foreland Basin which has proven

production of hydrocarbon. Recent study has stated possibility of new hydrocarbon discovery from Ainim pre-

tertiary deposit which is believed to have better TOC value than its in tertiary source rock. To image distribution of

subsurface pre-tertiary deposit which is deposited below limestone Kais Formation as seismic fail to penetrate

through this formation, magnetotelluric method is used as its ability to penetrate deeper depth. Frequency range

which is used in this research is between 320 to 0.0034 Hz. Magnetotelluric measurements were taken 35 times from

southeast to northwest and covered five Districts in West Papua. From magnetotelluric 1D analysis, distribution of

pre-tertiary deposit which consists of mudstone, sandstone and intercalation of muddy sandstone and coal,

characterized with range of resistivity between 10 to 100 Ωm is imaged in various depth and thickness. From 2D

inversion of magnetotelluric data, deeper and thicker pre-tertiary deposit is shown in southeastern of Manimeri,

Bintuni and Tuhiba District, then being more shallow and thin in northwestern of Tembuni and Meyado District. To

get a better understanding of subsurface pre-tertiary deposit and play concept in Bintuni Basin, more research should

be done in the northwestern of Tembuni and Meyado District.

Application of TEM technique in South-East Asia

Yuri A. Agafonov1, Igor V. Buddo

1, Olga V. Tokareva

1, M. Shukur M. Ali

2, and

Mustapha M. Salleh2

1JSC Irkutsk electroprospecting company

2Onyx Engineering Sdn Bhd

corresponding author: [email protected]

Abstract. Application of electromagnetic methods for oil and gas exploration is developing world-wide. Two main

types of EM methods are applied: natural source (MT) and methods with artificial source of EM field (TDEM,

FDEM). For hydrocarbon exploration on land high efficiency has transient electromagnetic method in frequency or

time domain mode. The role of EM methods is increasing at the areas with poor seismic data quality, non-structural

fields and zones with complicated structure of sedimentary cover. Joint interpretation of EM data with seismic or

other geological data is a way to reduce the risks and optimize the process of geophysical investigation. For oil and

gas exploration it is possible to study sedimentary layers resistivity at the depth interval from surface to basement

and also a lot of information can be received from induced polarization (IP) parameters. The paper is devoted to

technique of EM methods combination – TEM and EM-IP for oil and gas exploration, and possible ways of its

effective application. Electroprospecting surveys have been performed over one of the blocks in the Southeast Asia.

Two techniques were used: Transient Electromagnetic Soundings in Time Domain (TEM) and Induced Polarization

Electromagnetic method (EM-IP). The objective is to conduct a comprehensive study of the sedimentary cover using

TDEM. This includes mapping of zones with potential reservoirs properties from TEM, and to qualify these areas

with Induced Polarization (IP) anomalies, usually related to presence of hydrocarbon system.

OG-03

OG-04



39

Formation Factor Calculation of Digital Rock Images with

the Help of FEM

Muhammad Bisri Mustofaa), Umar fauzi

b), and Fourier D. E. Latief

c)

Earth Physics and Complex Systems, Faculty of Mathematics and Natural Sciences, Bandung Institute of

Technology, Jalan Ganesha 10, 40132, Bandung, Indonesia

a)


[email protected] c)

[email protected]

Abstract. Understanding of formation factor as a key role in identifying oil and gas reservoir is important. Studies

on this topic have been done by many researchers, e.g. by examining the relationship of formation factor with a pore

radius, grain shape, and many more microstructure parameters. In this paper, calculation of formation factor for

digital rock models with different pore shape are investigated. The models are generated based on random deposition

of grains with basic shape of sphere, ellipsoid, polyhedral, and pigeonhole. Formation factor calculations are

performed by computational techniques using finite element method (FEM) through energy approach, which has

been validated in advance by analytical approach. Among the analytical approaches used to validate the numerical

codes are series-parallel layers, the Brown’s equation, and Keller-Mendellson. Validation has been done both for 2D

and 3D models. The results show that deviation of FEM and analytical is less than 0.1. The study was conducted by

varying the value of porisity (i.e.: 0.10 to 0.30), the size of sample size (163 voxel-2563 voxels), and the porous rock

model parameters (i.e.: grain shape and grain parameters). Based on calculations, the trend is in accordance with

Archie’s law, with the value of the formation factor between 0.8- 1 and cementation exponent value between 0.7-1.5.

Reservoir Identification using Short Offset Transient

Electromagnetic Method

Muhammad Hasbi Assiddiqy and Warsa

Geophysical Engineering Department, ITB


Abstract. Short offset transient electromagnetic method (SHOTEM) is a time domain electromagnetic geophysical

method that can be used to obtain the variation of the resistivity of the subsurface as reference information for the

identification of anomalous body in particular reservoir. Beside the received signal obtained are free from the

sources signal influence, SHOTEM superior in terms of the depth range and resolution than using another transient

electromagnetic (TEM) configuration. This study used 18 points field data sounding obtained with SHOTEM

method. Several stages of data processing that utilizes wave properties, the principles of statistics, and numerical

approaches made to clean up the data from the noise, and then carried one-dimensional forward modeling and

inversion modeling using software IX1D to produce one-dimensional model of the subsurface resistivity. 18 one-

dimensional resistivity model interpolated to produce a two-dimensional image of the resistivity variations to

identify the body of anomalies in the subsurface area of the field data measurements. From the resulting model, there

is a high resistivity anomaly associated with the presence of a hydrocarbon reservoir 800 – 1000m under the surface

in the area of research. RMS error objective function are unstable and contain extreme distribution of resistivity

values in the 18 one-dimensional models generated raise a tendency that the models are not representative. The result

can be caused by the data that still contain noise as a result of the measurement system, noise due to the influence of

local geological features, and their incompatibility with the function of data modeling used.

OG-05

OG-06


40

Non-linear Inversion Modeling of TDEM Data for

Reservoir Characterization

Donny Prasetyo1, Warsa

1, Wahyu Srigutomo

2, and M. Rachmat Sule

1

1Geophysical Engineering Department, ITB

2Physics Department, ITB


Abstract. In order to reservoir characterization for CCS (carbon capture storage) in Gundih area, a TDEM (time

domain electromagnetic) or TEM (transient electromagnetic) exploration of deep target is addressed using a

grounded wire dipole source. The grounded electric source mode of TDEM method can potentially probe the depths

of hundreds to thousands of meters. Therefore this method has been popularly used for deep structure exploration,

such as reservoir characterization, geothermal investigation and ore prospecting. In our research, a TDEM data-

processing sequence consists of many different modules which may be applied before and after stacking. Most of

where these processing steps are now standardized. Here we would like to discuss the TDEM data-processing

techniques, which assist in removing the problem of periodic and sporadic noise, respectively: the improved, pre-

stack digital recursive filter and the selective stack. Based on singular value decomposition (SVD) scheme, it takes

the non-linearity of the inverse problem into account. The SVD resolution and variance analysis is performed on a

single cell at a time. A 1D model of TDEM data has been resulted from non linear inversion process using a damped

least-square SVD technique. TDEM data inversion method have been introduced and applied to both synthetic and

real data, which illustrate their importance in processing data from noisy area. Inversion modeling results of field

data have shown a Wonocolo layer formation which is a cap rock and Ngrayong formation as a target reservoir. This

suspected area has a probability to be a leakage area of reservoir also shown by this model. In the next step, this

method will be used after CO2injection formonitoring CO2mobility in the subsurface.

Magnetotelluric (MT) Layer Stripping to Identify Sub-

surface Resistivity Changes: Preliminary Results

Andry Deni Wardhana and Hendra Grandis

Dept. of Geophysical Engineering, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung

Jalan Ganesha 10 Bandung 40132, INDONESIA


Abstract. Magnetotelluric (MT) measurement can be applied to monitor resistivity change at depth, for example due

to fluid injection in EOR process. With the resistivity change limited in only one layer (limited depth extent) and a

well defined host, 1D modeling can be used for such situation. The resistivity changes of a layer in a 1D

environment give rise to a minor change in MT data (apparent resistivity and phase) at the surface. We proposed the

layer stripping method to calculate MT data changes as if the observation is made at the surface of a layer at depth.

For that purpose we reformulated the well-known 1D MT forward modeling resulting in an analytical recursive

formula that relates impedance at two consecutive layers. We used a synthetic layered model and the Monte Carlo

approach to estimate the result’s uncertainties. The layer stripping formula was also formulated by using other type

of 1D MT forward modeling, i.e. matrix multiplication method. The latter was intended to minimize the error

propagation when the calculation is made from the field data containing noise. However, both methods showed

equivalent results in terms of stability and sensitivity to data errors and their propagations to the final apparent

resistivity and phase sounding curves. The layer stripping calculation is unstable and has the greatest uncertainty at

short periods where the real and imaginary parts of the impedance tend to be equal, i.e. the homogeneous response.

Therefore, the layer stripping approach should be use with great cautions.

OG-07

OG-08


41

Rotation Analysis For Magnetotelluric Data at Buton

Field, Southeast Sulawesi

Lia Maryani1, a)

, Lucki Junursyah2, b)

, and Asep Harja1, c)

1Geophysics Department, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran,

Jl. Bandung-Jatinangor km. 21, Jatinangor 45363, Indonesia. 2Geological Agency

a)



[email protected]

Abstract. A geophysical investigation has been done using Magnetotelluric (MT) method, at hydrocarbon

prospected area, Buton Field, Southeast Sulawesi. The MT data has a good quality in the frequency range between

5.6-320 Hz (Time Series 3 and 4). In some measurement points, the data have no good quality (still under 75%).

After doing coherency analysis and time series analysis, the data quality have increased up to 75%. For better

interpretation, we doing cross power (XPR) analysis, and the data quality increased up to 90%. For identification

resistivity of subsurface, it has been done MT data processing and 2D inversion modelling. In general, the 2D MT

model was used for imaging subsurface structure which is near to field situation. But, the real structure is not same

anyway with the models. Then, it is necessary to analyze the strike direction preference, with rotating strike direction

the MT data. From the strike direction rotation, we can compare the MT data before rotated and after rotated. Then

we can use which is better for modelled and interpretation.

OG-09

42

Code Paper Title

NR-01 Delineation of Dolok Marawa Geothermal Prospect Area by Applying 2-

D Inversion that Utilize Magnetotelluric, Audio Magnetotelluric, and

Time Domain Electromagnetic Data

NR-02 Measurement of Subsurface Structures in Mount Telomoyo Geothermal

Area, Magelang Using 1-D Audio Magnetotelluric Method

NR-03 The Revealation of Structure Controlled Hotspring Using Passive Single

Component Electromagnetic Method

NR-04 Identification Of Water Spring, Water Flow Patterns and Quality Contents

of Soil Water Using Conductivity Measurement Direct (CMD),

Geoelectricity and Coring Methods. Case Study: Padjadjaran University

NR-05 Identification of Geothermal System Using 2D Audio Magnetotelluric

Method in Telomoyo Volcanic Area

NR-06 Resistivity Image beneath Parangwedang Geothermal Field (Indonesia)

Inferred from Magnetotelluric Data

NR-07 Water Table Monitoring around the Parangwedang Geothermal Field

(Indonesia) Inferred from Audio Magnetotelluric Data

NR-08 3-D Modelling for Exploration Iron Ore in Tanjung Mahuroy Village,

Central Kalimantan Using Geoelectrical Method IP and Dipole - Dipole

NR-09 Phase Tensor Analysis of Magnetotelluric data: Case Study of “X”

Geothermal Field Data

NR-10 Geothermal Potential in a Small Volcanic Island: Case Study Case at

Ternate Island

NR-11 Using Landsat Image 8 and GIS for Surface Mineral Analysis in the

Southern Bangka

NR-12 Magnetotelluric Static Shift Correction Using Time Domain

Electromagnetics Case Study: Southern Sumatera Geothermal Field

NR-13 Discovering “Hidden” Geothermal Reservoir in Blawan-Ijen Geothermal

Area (Indonesia) Using 3D Inversion of MT Data

NR-07

NR-08

NR-12

43

Delineation of Dolok Marawa Geothermal Prospect Area

by Applying 2-D Inversion that Utilize Magnetotelluric,

Audio Magnetotelluric, and Time Domain

Electromagnetic Data

Wiwid Joni1, 2

, Darharta Dahrin1, and Asep Sugianto

2

1Geophysical Engineering, ITB

2Geological Agency of Indonesia

Abstract. Dolok Marawa geothermal area is located in Simalungun regency, North Sumatera and categorized by

volcanic area. Geothermal indications of the area are presented by many manifestations of high temperature 370C -

650C at the surface. In order to delineate geothermal system area, we conduct the subsurface resistivity modelling of

magnetotelluric (MT) and audio magnetotelluric (AMT) data. By applying 2D inversion using Non-Linear

Conjugate Gradients algorithm, we generate the model inversion. Meanwhile, Time Domain Electromagnetic

(TDEM) data is used as a static shift correction for MT data. These data is obtained from geological agency's

measurement in 2015. The result models show that the third to the tenth profiles are interpreted to the presence of

cap rock with resistivity value < 20 Ohm-m in ±600 meters depth and reservoir with resistivity value 20 – 200 Ohm-

m is located in the western part of those profiles which are supported by MT and AMT resistivity map at 1000

meters depth. Dolok Marawa prospect area is about 8 km2 as a delineation result of MT, AMT, and constrained data.

Measurement of Subsurface Structures in Mount

Telomoyo Geothermal Area, Magelang Using 1-D Audio

Magnetotelluric Method

Achmad Fajar Narotama Sarjan1, a)

and Sintia Windhi Niasari2, b)

1Undergraduate Program of Geophysics, Universitas Gadjah Mada, Indonesia.

2Geophysics sub-Department, Universitas Gadjah Mada, Indonesia.

a)


[email protected]

Abstract. There are some of Geothermal prospects around Java Island. One of them are located in Mount Telomoyo,

Magelang, Central Java. The existence of hot spring manifestations in Mount Telomoyo shows the presence of

geothermal system. The upflow zone of this geothermal system was formed in the caldera of Mount Telomoyo,

while the outflow zone was formed around Candi Umbul. In addition, from the geological map shows a geological

structure assumed as a normal fault with southwest-northeast orientation. The aim of this research is to map the

subsurface properties in Mount Telomoyo using 1-D audio magnetotelluric method. Thus, we can determine the base

of clay cap layer in this geothermal system. The audio magnetotelluric method have been measured to model the

heat flow of Telomoyo geothermal system. The apparent resistivity, phase, and coherence values were obtained from

the field data acquisition. Then, the data were processed using 1-D inversion to determine the true resistivity value of

each layer in Mount Telomoyo, Magelang. The result from this investigation is a resistivity map which shows the

presence of clay cap characterized by a low resistivity layer. A layer below the clay cap with a medium resistivity

value interpreted as the reservoir of this geothermal system. This investigation is still in progress to acquire the exact

values of resistivity from each layer in Mount Telomoyo, Magelang.

NR-01

NR-02



44

The Revealation of Structure Controlled Hotspring Using

Passive Single Component Electromagnetic Method

Kevin Gardo Bangkit Ekaristia), Aditya Aries Furkhan

b), and Agra Adipta

c)

Geophysical Engineering Department, Faculty of Mineral Technology, Universitas Pembangunan Nasional

“Veteran” Yogyakarta

Jalan SWK 104, Depok Subdistrict, Sleman Regency, Special District of Yogyakarta

a)



[email protected]

Abstract. Karangsambung, Central Java is one of well known tectonically complex region in Indonesia which

became a huge geological interest in recent decades. Hotspring is a one of geothermal manifestation that has arisen

at Krakal, a local village in Karangsambung. The presence of this manifestation caused several speculations on its

genesis due the lack of local geological data. Recent geology studies defines Krakal hotspring particulary located at

Panosogan formation in which consists of claystone unit without any indication of associated structures and

mineralizations nearby. A sight of geologists fails on this peculiar case to interpret geological features beneath the

surface refering to this manifestation occurence. Thus, preliminary geophysical surveys are necessary to delineate

possible subsurface structures and mineralizations boundaries in which may affect or a byproduct of the

manifestation. Passive single component eletromagnetic is a cost effective and practical method which suits for

preliminiraly structural studies. This research constructs conductivity section and three dimentional conductivity

cube to seek desirable subsurface geological features. The analysis indicate the existence of a structural fault located

at south side of the hotspring which extend approximately ±40 m beneath the surface. A high anomalous closure

spreads thoughout East – West direction with a scale value of 20 A/m2 to 80 A/m2. Minor anomalous closure

identified as spots of clay minerals accumulation and cultural noise derived from surrounding residences. Secondary

data of amplification map expressed similiar relatively high anomalous closure throughout East – West direction

which indicates weak zones that caused by the corresponding structural fault.

Identification Of Water Spring, Water Flow Patterns and Quality Contents

of Soil Water Using Conductivity Measurement Direct (CMD),

Geoelectricity and Coring Methods. Case Study: Padjadjaran University

Aprillia Himatina Retnowati and Reza Fauziah

Bachelor Program of Geophysics, Padjadjaran University

[email protected]

Abstract. The aim of this research is investigating the water spring, distribution patterns and the flow of water, and

find out the water quality in Padjadjaran University area. There is a big pool named Arboretum which has not known

until now where the water source comes. Indicated that the water spring comes from the back part of the

Padjadjaran University because there is a soil water flow which is suddenly appears in the area. Geophysical

methods that used in this research are Conductivity Measurement Direct (CMD) , geoelectric resistivity, and coring.

Conductivity Measurement Direct methods used to delineate the lateral zone of the study area in order to obtain a

more significant area. The result values of this measurement methods mostly obtained 22. Furthermore, geoelectric

methods which is an active method is used to determine the distribution and the flow of soil water from the

indication area until Arboretum area. The measurement results of geoelectric methods produce cross sectional

resistivity which shows aquifer layers. To determine the quality and content of soil water in every measurement

point. SEM analysis is used for this case. Geological data is also used as a priori information to support the analysis

of the obtained results. The type of the rocks which is found in the area of this research is quaternary volcanic rock

which the geology products are potential of water sources. Those geophysical methods that has been used are

combined and correlated each other so we can get the expected results in the form of local water sources, water

distribution pattern and direction of water flow, and also the quality and contents of soil water. From there, we can

found out the water springs, as well as the distribution pattern of groundwater flow that leads to the Big Pool

Arboretum.

NR-03

NR-04

45

Identification of Geothermal System Using 2D Audio

Magnetotelluric Method in Telomoyo Volcanic Area

Arriqo’ Fauqi Romadlon1, a)




a)


[email protected]

Abstract. Geothermal area of Candi Umbul Telomoyo is one of geothermal fields in Indonesia. This geothermal

field located in the Grabag district, Magelang, Central Java. This geothermal field was formed in a volcanic quarter.

In this research aimed to identify geothermal system at Telomoyo volcanic area. There are surface manifestations

such as warm springs and altered rocks. Results of geochemistry study showed reservoir’s temperature was 2300C.

The Warm spring in Candi Umbul was the outflow zone of the Telomoyo geothermal system. The Telomoyo

geothermal system was indicated chloride-bicarbonate type of warm spring. In addition, the results of geological

mapping indicate that the dominant fault structure has southwest-northeast orientation. The fault was caused by the

volcanic activity of mount Telomoyo. We conducted survey with audio magnetotelluric method to find out more

information in the subsurface of Candi Umbul-Telomoyo area. We used non linear conjugate gradient to solve 2D

data inversion. Inversion results with hypothetically showed that the layer with low resistivity is 10 100 Ω.m which

is interpreted as a clay cap, high resistivity is 250 Ω.m which is interpreted as a heat source, and the medium

resistivity is 100 Ω.m which is interpreted as a reservoir. This mapping result was supported by geological and

geochemical studies. This research is still in progress to obtain quatitative result of subsurface resistivity in

Telomoyo geothermal system.

Resistivity Image beneath Parangwedang Geothermal

Field (Indonesia) Inferred from Magnetotelluric Data

Sintia Windhi Niasari

Geophysics Laboratory, Physics Department, Faculty of Mathematics and Natural Sciences, Sekip Utara, BLS

21, Yogyakarta, Indonesia.


Abstract. Two warm springs that indicate a signature of the Parangwedang geothermal field (Indonesia) are located

on the margins of the Indian ocean to the west in the distnace less than 100 m. Saline water of the ocean can increase

the bulk conductivity of the region and give an effect to magnetotelluric data, called ocean effect. This effect leads

us to propose that the anomalous conductivity in this region is affected by the ocean. Here we test this hypothesis by

using magnetotelluric data. Our synthetic magnetotelluric data reveal that the ocean effect appears in the long period

data, correspond to deeper part of the Parangwedang geothermal field. However, as our measurements were made

during normal solar activity and were made in dense population, long period of our measured data are very noisy.

From modelling of measured data, we imaged a shallow (around 60 m depths) layer of low resistivity (below 10

Ohm.m) beneath the Parangwedang geothermal field. This conductor can be interpreted as the water table. Below

this conductive layer, electrical resistivity increase by depth. We infer that the Parangwedang geothermal field is a

medium to low temperature geothermal system due to Miocene andesite and not due to a volcano. By absence of

smectite conductor alteration, the resistivity image in non-volcanic is different with volcanic geothermal systems.

Our interpretation is consistent with the geological, geochemistry and other geophysical studies from the

Parangwedang geothermal field, and explains the low temperature but high chloride (and low sulphate) of the fluids

observed on the warm springs.

NR-05

NR-06


46

Water Table Monitoring around the Parangwedang

Geothermal Field (Indonesia) Inferred from Audio

Magnetotelluric Data

Sintia Windhi Niasari

Geophysics Laboratory, Physics Department, Faculty of Mathematics and Natural Sciences, Sekip Utara, BLS

21, Yogyakarta, Indonesia.


Abstract. The Parangwedang geothermal field (Indonesia) is located very close to the Parangtritis beach, a very

popular local touristic destination. The Parangwedang itself, is popular and is used for spa since more than 30 years

ago. In the last five years, the number of visitors, both in the Parangtritis and the Parangwedang, increased

significantly. This means that the water consumption in this study area is also increase. Here we test this hypothesis

by using audio magnetotelluric data. From modelling of measured data, from 2010 and 2015 at the same location of

AMT site, we found a shallow layer of low resistivity (below 10 Ohm.m). This conductor can be interpreted as the

water table. Additionally, there is decreasing of water level in the last five years. On 2010, the shallow conductor

layer was around 40 m depths, but on 2015, the low resistivity anomaly was at 60 m depths. This indicates a high

demand of water for consumption and for spa. Some policy from the local government should be made to prevent

excessive water utilization.

3-D Modelling for Exploration Iron Ore in Tanjung

Mahuroy Village, Central Kalimantan Using Geoelectrical

Method IP and Dipole - Dipole

Bryna Mustikaa) and Niken Ramadianti

b)

Geophysical Engineering Departmenr, Faculty of Technology Mineral, University of Pembangunan Nasional

“Veteran” Yogyakarta

a)[email protected]

b)[email protected]

Abstract. Indonesia has abundant mineral resources and much used in the mining industry, one of which is iron ore.

Iron ore is the raw material metal industry are included in group B. Lester Brown of the Worldwatch Institute has

estimated that iron ore could run out within 64 years based on a conservative extrapolation of 2% growth per year.

This is because the reserves of iron ore began to decrease. Therefore, as explorationist we do the exploration, one of

which is exploration of mineral resources. One of the mineral resources that may be explored is iron ore. In the

exploration of iron ore can be done by using geophysical methods, one of which methods is geoelectrical method.

Exploration of this iron ore is in Tanjung Mahuroy Village, Cental Kalimantan. Configuration of geoelectical

method that used in this exploration are Dipole-Dipole and Induced Polarization. Based on the result of acquisition

that have been processed, the range of resistivity value that were thought to be iron ore is 2000 ohm.m and value of

chargeability is 250. Iron ore is estimated to be at a depth of 60 meters. By using 3D modelling it can be seen the

spreading direction of this iron ore.

NR-07

NR-08

47

Phase Tensor Analysis of Magnetotelluric data: Case

Study of “X” Geothermal Field Data

Mayvita Dewi1, Widodo

1, and Imam B Raharjo

2)

1Geophysical Engineering, Institut Teknologi Bandung, Basic Science Center-B Building, 2nd Floor,

Ganesha St. No. 10, 40132, Bandung, Indonesia 2PT. Pertamina Geothermal Energi


Abstract. Magnetotelluric method is commonly used for geothermal investigation due to its ability to image changes

in resistivity distribution from the greater depth. However, the field magnetotelluric data is affected by distribution

of geometry and conductivity heterogeneity near the surface. It can distort the magnetotelluric data response. In

order to resolve the problem, the phase tensor analysis has been conducted in this paper. Phase tensor analysis has

been implemented to “X” geothermal field data. The results show that the dimensionality of the area is closed to 2D

from the frequency of 0.5 to 10-2 Hz, and is 3-D for lower frequency. While, the resistivity analysis has shown that

the strike direction of the measurement area is N0oE – N18oE, with 90o ambiguity, or N90oE-N108oE. The resistivity

increases with the depth and a conductive layer detected on the southern part of the study area. The results of phase

tensor analysis have been applied to modeling of geothermal system. This model consists of layers with varying

resistivity which were interpreted as lava flows at depths of 0-500 meters, strong conductor which was interpreted as

geothermal clay cap, a layer with resistivity value of 10-60 Ωm meters up to a depth of 2,000 meters which was

interpreted as geothermal reservoir, and layer with resistivity values of 60-80 Ωm which was interpreted as a

transition zone between the reservoir with the heat source.

Geothermal Potential in a Small Volcanic Island: Case

Study Case at Ternate Island

Ramdani Salam 1, a)

and Rahim Achmad 2, b)

1 Faculty of Geography Universitas Gadjah Mada, Indonesia

2 Physics Dept. of Khairun University, Indonesia

a)


[email protected]

Abstract. In this paper we report the continuation of previous observation of hot spring phenomenon in northern

Ternate island. The hot spring location spreads unevenly with temperature ranging from 29 °C to 35.5 °C along the

shore line. Geomagnetic measurements and determination of chemical and physical water properties have been

carried out to find the cause of unevenly hot spring distribution . This research intends to reveal geothermal

potential in a small volcanic island. The result of geomagnetic measurements, showed low magnetic anomalies as

demagnetization rock by heat. Magnetic anomaly map shown any fault structure alignment with the northeast –

southwest strike direction. The fault structures create path of heat. The result of chemical and physical water

properties measurement also agree with geomagnetic measurement that show indication out flow of geothermal

system. The heat source does not come directly from magma chamber but passes through fracture rock as known as

the out flow geothermal system.

NR-09

NR-10

48

Using Landsat Image 8 and GIS for Surface Mineral

Analysis in the Southern Bangka

Franto1, 2

, Subagyo Pramumijoyo1, and Lucas Donny Setijadji

1

1Departement of Geological Engineering,Universitas Gadjah Mada, Yogyakarta

2Department of Mining Engineering, Bangka Belitung University


Abstract. Utilization of remote sensing data in mineral mapping of the surface of arid and semi-arid areas shows the

success rate is quite good, because the surface of the mineral occurrences easily captured by satellite sensors. But it

would be different for tropical areas with dense vegetation a major problem, thus requiring image enhancement

method that is able to minimize disturbance of vegetation in mineral exploration.This study uses Landsat 8 And SIG

For Analysis Surface Mineral In Southern Bangka Island. The data analysis was also conducted by using defoliant.

Defoliant Technique is one of the main methods of sharpening remote sensing imagery serves to reduce disturbance

of vegetation in mapping the mineral surface, by analyzing the process Directed Principal Component of the two

ratios channel Principle Component Analysist, success in mineral mapping set of abilities which the input of the

ratio of the channel, where the ratio the first line contains information about the target minerals, while the ratio of the

second channel contains noise information.The results were good in determining the mineral resources (Hematite,

Quartz, Limonite, Kaolinite) in the study area.

Magnetotelluric Static Shift Correction

Using Time Domain Electromagnetics

Case Study: Southern Sumatera Geothermal Field

Ramadhani Yasyfi Cysela1, a)

, Asep Harja1, b)

, and Tony Rahadinata

2

1Department of Geophysics, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran

2Geophysicist of Pusat Sumber Daya Mineral Panasbumi dan Batubara, Geological Agency

Ministry of Energy and Mineral Resources of Indonesia

a)


[email protected]

Abstract. The integrated survey of geology, geochemist, and geophysics in area X, Southern Sumatra, shows a

geothermal potential. The potential site in Southern Sumatra have rough topographical condition. This topography

condition, causing a static shift in magnetotellurics (MT) data on apparent resistivity curve. The data of

magnetotellurics are really vulnerable to shifting because of topographic effect or an in-homogeneity near surface.

To overcome a static shift in MT data, we used a method that not influenced by static shift effect which is TDEM

method. TDEM is an active electromagnetic method which have effective range in 10-500 meter below surface so

that is highly recommended to do TDEM method and MT together because MT data have poor resolution in shallow

zone. This research will showing an influence of static shift in MT method with TDEM data at geothermal site,

Southern Sumatra.

NR-11

NR-12

mailto:Corresponding%20author:%[email protected]

49

Discovering “Hidden” Geothermal Reservoir in

Blawan-Ijen Geothermal Area (Indonesia) Using

3D Inversion of MT Data

Yunus Daud1, a)

, Wambra Aswo Nuqramadha2, Fikri Fahmi

2, Surya Aji

Pratama2, Khalif Radhiyya Rahman

3, Wisnu Subroto

3

1Master Program of Geothermal Exploration, Universitas Indonesia, Depok Campus, Indonesia

2PT NewQuest Geotechnology, Depok, Indonesia

3PT Medco Cahaya Geothermal, Jakarta, Indonesia

a)

Corresponding author: [email protected].

Abstract. Blawan-Ijen Geothermal Area is located in the Banyuwangi and Bondowoso Districts in the east Java

Province. The occurrence of geothermal system is probably related with Kendeng Caldera with diameter about 15

km. Unimpressive surface manifestations are found in the northern caldera margin within Blawan area, including

bicarbonate springs with temperature between 35 – 50OC. The only “impressive” manifestation is Ijen crater lake

with abundant solfatara located in the eastern margin of the caldera. Unfortunately, the fluid has extremely low pH

of less than 0.3. The rest of the caldera has no other surface manifestations. Accordingly, the crucial questions are:

(1) is there promising geothermal reservoir exists within Kendeng caldera? (2) if yes, does the fluid have high

temperature with neutral pH? (3) where is the promising zone (high temperature, high permeability and neutral

fluid)? Those questions are challenging to answer within such “hidden” geothermal area. To answer the questions,

MT data is optimized by employing careful and proper data processing before applying 3-D inversion. According to

the reprocessing and 3-D inverse modeling of 67 MT data, the prospect zones is identified which are located at the

central part of Blawan-Ijen geothermal prospect. In order to determine drilling location, additional MT survey were

carried out which was focused at the prospect areas. A number of 30 MT points were surveyed. All the 97 MT data

(including the additional data) were then inverted using 3-D inversion approach. The additional MT data give more

detailed information of the subsurface condition, especially the promising zone in the central part of the Kendeng

caldera. The promising zone is well correlated with the youngest volcanic activity, where indicated upflow (in the

central part) and outflow zones (in the southern part) are controlled by geological structure in which the boundary

could be clearly delineated. Drilling target was then recommended to test the indicated upflow zone. The slim hole

drilling program, which the total depth reached 2000 m, finally discovered high temperature (283oC) and neutral

reservoir in Blawan-Ijen geothermal area. This is one example of the 3-D MT inversion role for discovering

“hidden” geothermal reservoir.

NR-13

50

Code Paper Title

EV-01 Investigation of Cikapundung River’s Sedimentation Using 2D Resistivity

Method

EV-02 Plug Identification in Drainage System Using Electromagentic Wave

EV-03 Identifying Potential Ground Movement as a Landslide Mitigation

Approach using Resistivity Method

EV-04 Innovation in Evacuation of Natural Disaster with GPR Method

EV-05 Waste Disposal Mapping with Electrical Resistivity Tomography case:

Leuwigajah Landfill

EV-06 Investigation of Buried Paleochannel in Rumpet Village Eastern Banda

Aceh using Electromagnetic Induction Method

EV-07 GPR Application to Investigate Soil Cracks Persistence in Cianjur

Landslide

EV-08 New Instrumentation Device, Based on Resistivity for Agricultural

Geophysics

EV-09 The Study of Mudrock Resistivity in Northwestern Peninsula Malaysia

Using Electrical Resistivity Survey

EV-10 Slope Monitoring Using 2-D Resistivity Method at Sungai Batu, Pulau

Pinang, Malaysia

EV-11 Innovation of Floating Time Domain Electromagnetic Method In The

Case of Environmental Geophysics

EV-12 A Horizontal Electrical Mapping Method for Agricultural Soil Survey in

West Java Area with New Instrumentation Device

EV-13 Determination of Slope Failure Using 2-D Resistivity Method

EV-14 Porosity Determination from 2-D Resistivity Method in Studying the

Slope Failures

EV-15 Assessment of Leachate Infiltration from Piyungan Landfill Using

Electrical Resistivity Method

EV-16 Genesis of Mujil Hill has been Revealed: Using Audio Magnetotelluric

(AMT) Profiling

EV-17 Use of Electrical Geophysical Methods for Supporting Agricultural

Practices

EV-18 Innovation for Soil Studies with Electromagnetic Induction Techniques

EV-19 Applied EM and Resistivity methods for near surface Investigation

Arround Unpad Jatinangor

51

Investigation of Cikapundung River’s Sedimentation

Using 2D Resistivity Method

M. Dika Arzaldi, M. Izzuddin Prawiranegara, Emirza Faisal D., Arzalia

Wahida, and Widodo

Geophysical Engineering Department, Faculty of Mining and Petroleum, Institut Teknologi Bandung

Jl. Ganesha No. 10, Kota Bandung, Jawa Barat, 40132


[email protected]

Abstract. High rainfall rate in Indonesia makes the outcrop located in the upstream areas easily eroded and some

rocks carried by the water flow towards the downstream areas. This research is done in order to identify the silting of

Cikapundung’s River in Bandung. The method used is 2D resistivity method for mapping sedimentation of

Cikapundung’s River. The data was taken in Kampung Padi Residence, Cisitu, Bandung, West Java. Geological

observation’s results show that top layer consists of alluvial’s sedimentation, basalt tuff, and volcanic conglomerate.

Basement of river’s flow is volcanic conglomerate which has eroded and alluvial’s sedimentation. Discussion’s

results show that Cikapundung’s river has sedimentation’s thickness until 13 m. This sedimentation consists of top

soil and conglomerate rocks. Furthermore, from data processing’s result there is an indication that ancient

Cikapundung’s river, in meander section has already eroded therefore river’s flow shifted to south.

Plug Identification in Drainage System Using

Electromagentic Wave

Arifa Hijriani, Aji Surya Utama, Andrianus Boas, M. Ridho Mukti, and Widodo

Geophysical Engginering, Bandung Institute of Technology, Ganesha St.

Corres[onding author: [email protected]

[email protected]

Abstract. The evaluation of drainage system’s performance is an important thing to do to prevent flooding.

Conventionally, the government evaluates the drainage system by opening one by one the lid of drainage and find

the plug manually. This method is not effective and efficient because this method need many people, much time and

relatively expensive. The purpose of this paper is to identify plugs in drainage system in G street at Bandung

Institute of Technology by using electromagnetic wave. Ground Penetrating Radar (GPR) is one of geophysics

method that using electromagnetic wave with high frequency. GPR is a non-destructive method with high resolution

imaging for shallow depth (~100m) and relatively cheap. We could identify the plug without opening the lid

manually so that we could save much time. GPR’s sensitivity is depends on resistivity, magnetic permeability, and

permittivity of an object. The result of this research is we could identify the plug on the radargram that observed by a

build-up amplitude anomaly.

EV-01

EV-02

52

Identifying Potential Ground Movement as a Landslide

Mitigation Approach using Resistivity Method

F. N. Izzati, Z. S. Laksmana, B. Marcelina, S. S. Hutabarat, and Widodo

Geophysical Engineering, Bandung Institute of Technology, Jalan Ganesha No. 10-12, Bandung, 40116


[email protected]

Abstract. Landslide is defined as a form of ground movement in which land mass suddenly fails downward a slope

as a result of gravity. One of the mitigative approaches into investigating landslide is to identify a potential slip zone

using resistivity method. In this study, we chose to acquire the resistivity data using Wenner array as this array

provides a robust resolution in mapping lateral resisitivity variations. This method will generate a contour map

potraying the distribution of resistivity values of the subsurface. Beforehand, 2-dimensional forward modelling is

done to acquire an expected ideal result of possible potential slip zone. Landslides are affiliated with a low resistivity

zone that is located between two high resistivity zones. We conducted this study in a ground slump in Jalan Citra

Green, Northern Bandung, in which the area is comprised of mostly unconsolidated soil. By applying a least-square

inversion to the resistivity data obtained, we attained resistivity values of 10-200 Ωm. Based on the inversion result,

we manage to identify a low resistivity zone of 10-20 Ωm spanning from the surface to approximately 10 meters

deep. In conclusion, further investigations are needed to determine whether the low resistivity zone is associated

with potential slip zone as our data is limited to a single line.

Innovation in Evacuation of Natural Disaster with GPR

Method

Rianty Kusuma Dewi, Adityo Kurniawan, Reyhan Fariz Taqwantara, Farras M.

Iskandar, Taufiq Ziyan Naufal, and Widodo

Geophysical Engineering, Bandung Institute of Technology, Ganesha St. Indonesia.

Correspondence author: [email protected]

[email protected]

Abstract. Indonesian is one of the most seismically active regions in the world and has very complicated plate

convergence because there are meeting point of several tectonic plates. The complexity of tectonic features causes a

lot of natural disasters such as land slides, tsunamis, earth quakes, volcanoes eruption, etc. Sometimes, the disasters

occurs in high populated area and causing thousands to millions of victim been buried under the rumble.

Unfortunately, the evacuation still uses the conventional method such using rescue dogs whereas the sensitivity of

smell is decrease when the victims buried under the level of the ground . The purpose of this study is to detect

buried bodies using GPR method, so it can enhance the effectiveness and the efficiency in looking for the disaster

victims. GPR method is used because it can investigate things under the ground. A detailed GPR research has been

done in Cikutra Graveyard, Bandung, with corpse buried two week until two years before the research. The radar

profiles from this research showed amplitude contras anomaly between the new corpse and the old ones. We

obtained the amplitude contras at 1.2-.1.4 metres under the surface. This method proved to be effective but still need

more attention on undulated surface and non-soil areas.

EV-03

EV-04

53

Waste Disposal Mapping with Electrical Resistivity

Tomography case: Leuwigajah Landfill

Erisha Aryanti, Ahmad P. Ardi, Muaz Almunziri, Zael Yahd Xanggam, Adino

Eleazar, and Widodo

Department of Geophysical Engineering, Institut Teknologi Bandung


[email protected]

Abstract. Leuwigajah landfill is a landfill located in Cimahi, about 12 km south of Bandung city, West Java

Province, that has an environmental and social problem that caused aquifer contamination due to the big amount of

waste from Bandung city, Cimahi and Bandung regency. The research is to map the geology structure and to study

the leachate towards aquifer layer below Leuwigajah landfill. Here, we present the study of Leuwigajah landfill

subsurface using Electrical Resistivity Tomography (ERT). ERT is one of the most promising prospecting

techniques mainly concerning its effective contribution to resolve several environmental problems, was applied for

the geophysical modeling. ERT is a robust imaging method the theory and implementation of which are well

documented in geophysical research literature. The geological setting comprises clayed weathered layer, fractured

andesitic dike. Due to the above-mentioned geological singularity and in the light of the requirement for an

environmentally safe construction of the landfill, an ERT survey was carried out with dipole-dipole array, 78 m of

acquisition line and 6 m of electrode spacing. The model consists of 4 layers below the Leuwigajah landfill and

andesitic fracture until depth of 18.7 m below the surface.

Investigation of Buried Paleochannel in Rumpet Village

Eastern Banda Aceh using Electromagnetic Induction

Method

Muhammad Yanis1, Muzakir

2, Marwan

2, and Nazli Ismail

3

1Physics Department, Syiah Kuala University

2Department of Geophysical Engineering, Syiah Kuala University 3Graduate Program in Disaster Science, Syiah Kuala University


Abstract. The delta of the Aceh River dominates the coastal landscape around Banda Aceh. The areas were

constructed by paleochannel activities in the past. We propose to learn the past history of these formation, so that we

might provide a better understanding of paleotsunami impact around coastal area of Banda Aceh. As a preliminary

study, we have conducted electromagnetic induction method measurement in the suspected of paleochannel area in

Rumpet village, eastern of Banda Aceh. The EM induction measures an apparent electrical conductivity at the

surface, which represents a weighted average of the electrical conductivity distribution over a certain depth range.

The measurements were performed along a profile with 250 meters length and 10 meter spacing between stations

crossing the suspected buried paleochannel. The apparent conductivity data collected along the profile clearly reflect

geometry of the expected paleochannel in the area. Compared to electrical resistivity methods, the EM induction data

reveal almost the same trend as showed in the electrical resistivity model. Therefore the EM induction method is

potentially used for paleochannel investigation, especially in preliminary study since the EM induction method can

be operated fast and costly effective in large areas surveys.

EV-05

EV-06

54

GPR Application to Investigate Soil Cracks Persistence in

Cianjur Landslide

S. Irawan1, a)

, R. R. Aly1, R. Syahputra

2, T.H.W. Kristyanto

2, b), and A.S.

Tempessy2

1Geophysics Study Program. FMIPA, Universitas Indonesia, Depok, Indonesia

2Geology Study Program. FMIPA, Universitas Indonesia, Depok, Indonesia

a)

corresponding author: [email protected] b)

[email protected]

Abstract. Cianjur region, located in West Java, is one of regions in Indonesia with high rain intensity. A medium

land movement may be inevitable. The presence of joints on sandstone outcrops conducts as water access and

accelerates weathering process. The survey aims to study the continuity of the soil cracks that develop in the body of

slope. Review of geophysical techniques applied to landslide reconnaissance pointed out the large number of

available methods. This survey used Ground Penetrating Radar method to study landslides in both favorable and

unfavorable light. Ground Penetrating Radar, GPR, was the method that adopts electromagnetic wave propagation to

map subsurface properties. GPR was one of the effective methods to delineate subsurface with the highest resolution

in the shallow depth, even it had highly variation results corresponded to complex of geological features and clay-

rich materials. To constrain GPR result for delineating subsurface, the bore-hole data gave the boundary of

interpretation and provided the fittest mapping. The combination of GPR and well data could show the weak zone of

formation by presenting the soil crack in the formation target. The result section showed soil crack continuation into

deeper part of the layer, most of section then showed the crack occurrence is dominated in the above 200ns. Crack

density is affected by terrain; higher layer has lower density value. The area was approximately affected by

landslides that usually exhibited dramatic spatial and temporal variations of lithological and hydrogeological

conditions. It will need further survey to know the effect of soil crack toward the sliding surface of the landslide

from other surveys.

New Instrumentation Device, Based on Resistivity for

Agricultural Geophysics

Shallom Samuel Harmany1

and Tedy Setiawan2

1Undergraduate Program of Geothermal Engineering, Institut Teknologi Bandung

2Global Geophysics Group, Institut Teknologi Bandung


Abstract. Geophysical methods are used to map geological structures and find prospect underground. But due to

technological advancement, geophysical method become a valuable tool in any agroecosystem. Geophysical method

can observe variability of soil containment. The three geophysical methods predominantly used in agricultural are

resistivity, electromagnetic induction, and ground penetrating radar (GPR). In this paper, we are using resistivity

method for mapping the variability of soil containment with our own device. Resistivity can be variated due to soil

containment, pore, and the material itself. In agricultural, it is important to recognize the fertility of the soil in order

to determine the correct treatment for a specific field. In order to measure resistivity, we can use a regular

resistivitymeter, but it’s not really applicable due to its weight and very time consuming process. We are developing

a new device that use to measure resistivity, portable, rapid, and user friendly. We already test our first prototype and

compare it with McOhm OYO. The result shows a good correlation (correlation of +0.9) between our new device

and McOhm Oyo. In this paper we only cover our initial step of research and we hope that we can develop better

instrument for this application in the future.

EV-07

EV-08


55

The Study of Mudrock Resistivity in Northwestern

Peninsula Malaysia Using Electrical Resistivity Survey

Hazrul Hisham, M.M. Nordiana, and Teoh Ying Jia

Geophysics Section, School of Physics, Universiti Sains Malaysia 11800 Pulau Pinang, Malaysia.


Abstract. Mudrock is a type of sedimentary rock whose original constituents are clays and muds. Mudrocks are fine

grained siliciclastic which include mudstone and claystone depending on the grain size. The colour of mudstone is a

function of its minerology content and geochemistry processes. One common sedimentary structure of mudrocks is

lamination due to variations in grain size and composition changes. The importance of mudrocks is as a mixture for

cement and to produce brick used for building structure. This research emphasizes on the resistivity value of

mudrocks; claystone and mudstone which exist in northwestern of Malaysia. Mudstone of Kubang Pasu Formation,

red mudstone and grey mudstone of Chepor Member and claystone of Semanggol Formation were chose as the study

area as each of the mudrock was formed in a different environmental condition. Electrical resistivity survey was

conducted on top of the outcrops using Wenner – Schlumberger array with 2 m electrode spacing. The data was

processed using Res2Dinv software to get the inversion model resistivity and the results were imported to Surfer10

software for labelling purposes. The mudstone resistivity value of Kubang Pasu Formation formed by depositional of

calm water gives resistivity value from 20 – 120 Ωm. The red mudstone of Chepor Member formed at high oxidation

environment gives resistivity value of 15 – 100 Ωm contrast to grey mudstone which formed under low oxidizing

condition gives 120 – 500 Ωm resistivity value. The claystone of Semanggol Formation formed from shallow

depositional environment gives resistivity value from 400 – 1000 Ωm. As a conclusion, electrical resistivity survey

was successfully applied in differentiating the type of mudrocks. Also mudrocks formed from different depositional

environment gives different values of resistivity.

Slope Monitoring Using 2-D Resistivity Method at Sungai Batu,

Pulau Pinang, Malaysia

Muhamad Iqbal Mubarak Faharul Azman1, a)

, Azim Hilmy Mohd Yusof1, b)

, Nur Azwin

Ismail1, c)

, and Noer El Hidayah Ismail2, d)

1Geophysics Department, School of Physics, 11800 Universiti Sains Malaysia, Penang, Malaysia

2Department of Geology, Faculty of Science, Universiti of Malaya, 50603 Kuala Lumpur, Malaysia

. a)




[email protected]

Abstract. Slope is a dynamic system of geo-environmental phenomena that related to the movement of the soil and

rock masses. In Pulau Pinang, the occurrence of slope related phenomena such as landslide and rock fall has become

a huge issue especially during rainy season as the government would have to invests more for the people safety. 2-D

resistivity method is one of the geophysical methods that can be apply to overcome this issue thus prepare

countermeasure actions. Monitoring is one of the common acquisition technique that has been used in solving such

issue. This technique was applied to identify and monitor changes at the suspected area and thus, countermeasure

steps can be taken accordingly and not blindfolded. Starting from August until October 2016, a 200-meter survey

line of 2-D resistivity survey had been conducted monthly at Sungai Batu, Pulau Pinang slope for monitoring

purpose. The results showed that between distance 0 – 120 meter, some countermeasure steps need to be taken as the

inversion model of 2-D resistivity indicated that this part consists of weathered granite (550 – 1500 ohm-m). This

may be hazardous especially during rainy season as they may be loose thus triggering movement in the soil and rock

masses or worse to be collapse. The saturated zone was also found at distance 100 – 120 meter with resistivity value

< 250 ohm-m which may cause slope failure. Saturated zone became a factor especially during rainy season due to

the exceeded water content in the subsurface triggering the water to wash out the soil in order to achieve new

equilibrium state. As a conclusion, monitoring slope using 2-D resistivity method is indeed helpful in overcoming

landslide and rock fall issue as pre-countermeasure.

EV-09

EV-10

56

Innovation of Floating Time Domain Electromagnetic

Method In The Case of Environmental Geophysics

Siti Nurjanah 1 and Widodo

2

1Undergraduate Program of Geophysical Engineering, Institut Teknologi Bandung

Basic Science Center-B Building, 2nd

Floor, Ganesha St. No. 10, 40132, Bandung, Indonesia 2Lecturer of Geophysical Engineering, Institut Teknologi Bandung


[email protected]

Abstract. Geophysics has some methods that can be used to reveal the subsurface structure of the earth. The

physical features obtained from the acquisition then analyzed and interpreted, so that it can be a great lead to

interpreting the physical contents (rock), determine its position and its distribution. Geophysical methods also can be

used to help the environment contamination survey, which is referred to environmental geophysics. There are many

sources of pollution that can harm the nature, for example, the source in the form of solid waste, liquid waste

containing heavy metals, or radioactive, and etc. As time passes, these sources might settle in any sedimentary area

and become sediments. Time domain electromagnetic (TDEM) is a trustworthy method to detect the presence of

conductive anomaly due to sediment accumulation. The innovation of floating TDEM created to maximize the

potential of the method so that it can be used in aquatic environments. The configuration of TDEM modified using

pipes and tires during the process of measurements. We conducted numerical simulation using Levenberg-Marquardt

and Occam Algorithms towards the synthetic model to make sure the capability of the proposed design. The

development of this innovation is expected to be very useful to repair the natural conditions, especially in the water.

A Horizontal Electrical Mapping Method for Agricultural

Soil Survey in West Java Area with New Instrumentation

Device

Edner Lumenta1 and Tedy Setiawan

2

1Undergraduate Program of Geophysical Engineering, Institut Teknologi Bandung

2Global Geophysics Group, Institut Teknologi Bandung

Abstract. Agricultural geophysics survey still practically new and in agricultural geophysics survey the important

parameter is soil properties. Soil survey in geophysics often used resistivity, electromagnetic induction (EMI), and

ground penetrating radar (GPR) because those methods are quick and can estimate many soil properties, such as

salinity, stone content, and groundwater depths, but they cannot give the information about soil property variations

within a soil profile. Wenner array often used to define soil apparent resistivity in shallow depth. Wenner array can

easily calculated soil apparent resistivity in an area and the instrument sensitivity is not as crucial as with other array

geometries. Relatively small current magnitudes are needed to produce measurable potential differences. The

disadvantages are that for each sounding, all of the electrodes have to be moved to a new position. The most

common resistivity method instruments for soil mapping used cable because they can be used with many array

option, this new instrument is designed only to measure shallow depth and with this new instrument we can measure

shallow soil properties faster, easier, and cheaper. This instrument has been tested and show a great result, so in this

paper we will measure the soil properties in west java area, so we will know if these areas are good for planting or

not.

EV-11

EV-12

57

Determination of Slope Failure Using 2-D Resistivity

Method

M.M. Nordiana a)

, Rosli Saad b)

, I.N. Azwin

c), and Andy Anderson Bery

d)

Geophysics Section, School of Physics, Universiti Sains Malaysia, Glugor

11800 Pulau Pinang, Malaysia.

a)




[email protected]

Abstract. Landslides and slope failure may give negative economic effects including the cost to repair structures,

loss of property value and medical costs in the event of injury. To avoid landslide, slope failure and disturbance of

the ecosystem, good and detailed planning must be done when developing hilly area. Slope failure classification and

various factors contributing to the instability using 2-D resistivity survey conducted in Selangor, Malaysia are

described. The study on landslide and slope failure was conducted at Site A and Site B, Selangor using 2-D

resistivity method. The implications of the anticipated ground conditions as well as the field observation of the actual

conditions are discussed. The results were supported by borehole records and soil resistivity test of the selected soil

samples. Nine 2-D resistivity survey lines were conducted in Site A and six 2-D resistivity survey lines with 5 m

minimum electrode spacing using Pole-dipole array were performed in Site B. The data were processed using

Res2Dinv and Surfer10 software to evaluate the subsurface characteristics. 2-D resistivity results from both locations

show that the study areas consist of two main zones. The first zone is alluvium or highly weathered with the

resistivity of 100-1000 Ωm at 20-70 m depth. This zone consists of saturated area (1-100 m) and boulders with

resistivity value of 1200-3000 m. The second zone with resistivity values of > 3000 m was interpreted as granitic

bedrock. The study area was characterized by saturated zones, highly weathered zone, highly contain of sand and

boulders that will trigger slope failure in the survey area. Borehole record and soil resistivity test of the samples are

well correlated with 2-D resistivity results. Based on the results obtained from the study findings, it can be

concluded that 2-D resistivity method is useful method in determination of slope failure.

Porosity Determination from 2-D Resistivity Method in

Studying the Slope Failures

Umi Maslindaa), M.M. Nordiana

b), and A.A. Bery

c)

Geophysics Section, School of Physics, Universiti Sains Malaysia

11800 Minden, Penang, Malaysia

a)



[email protected]

Abstract. Slope failures have become the main focus for infrastructures development on hilly areas in Malaysia

especially the development for tourism and residential. Lack of understanding and information of the subsoil

conditions and geotechnical issues are the main cause of the slope failures. The failures happened are due to a

combination of few factors such as topography, climate, geology and land use.2-D resistivity method was conducted

at the collapsed area in Selangor. The 2-D resistivity was done to study the instability of the area. The collapsed

occurred because of the subsurface materials was unstable. Pole-dipole array was used with 5 m minimum electrode

spacing for the 2-D resistivity method. The data was processed using Res2Dinv software and the porosity was

calculated using the Archie’s law. The results show that the saturated zone (1-100 Ωm), alluvium or highly

weathered rock (100-1000 Ωm), boulders (1600-7000 Ωm) and granitic bedrock (>7000 Ωm). Generally, the slope

failures or landslides occur during wet season or after rainfall. It is because of the water infiltrate to the slope and

cause the saturation of the slope which can lead to landslides. Then, the porosity of saturated zone is usually high

because of the water content. The area of alluvium or highly weathered rock and saturated zone have high porosity

(>20%) and the high porosity also dominated at almost all the collapsed area which means that the materials with

porosity >20% is potential to be saturated, unstable and might trigger slope failures.

EV-13

EV-14



58

Assessment of Leachate Infiltration from Piyungan

Landfill Using Electrical Resistivity Method

Jaingot Anggiat Parhusip1, 2, a)

, Agung Harijoko1, b)

, Doni Prakasa Eka Putra1, c)

,

and Wiwit Suryanto3, d)

1Jurusan Teknik Geologi Fakultas Teknik Universitas Gajah Mada, Yogyakarta Indonesia

2Jurusan Teknik Pertambangan Fakultas Teknik Universitas Cenderawsaih, Jayapura Indonesia

3Jurusan Geofisika Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Gajah Mada, Yogyakarta

Indonesia.

a)




[email protected]

Abstract. The purpose of this study is to estimate leachate infiltration in the area near Piyungan landfill. Leachate

flow in the Banyak river through paddy fields on the north side Piyungan landfill. Soil samples were collected at the

point of X = 437 172m; Y = 9130495m; Z = 75.5m. Samples saturated using a fluid (distilled water + leachate) on

12 levels concentration. Resistivity values of saturated soils obtained between 5.5 to 9.7 Ωm. This value is used to

interpret sandy clay bedding. Groundwater samples obtained from wells around the center of the geoelectric line has

resistivity 24.39 Ωm. survey resistivity is done by using the configuration Wenner-Schlumberger multi-electrode /

multi-channel. Minimal electrode distance is 5m and distance maximum is 190m. the line is 3000NW perpendicular

to the fault in the area. This line was cutting the Banyak river that drains leachate from Piyungan landfill. Soil

resistivity in the site ranged from 2- 60 Ωm. In the Eastern part of the line that cut the river at a point 135 m,

resistivity is 2-10 Ωm were at 10-12 m depth. This was estimated as watering andesitic breccias which infiltrated by

leachate. Around the line point, 40-130m contained resistivity 2-12 Ωm to depths of 15m is expected as a layer of

sandy clay saturated water. Resistivity between 20- 60 Ωm estimated as tuffaceous sandstone layer.

Genesis of Mujil Hill has been Revealed: Using Audio

Magnetotelluric (AMT) Profiling

Rahmaniab)

and Wiwit Suryantoa)

Department of Physics, Faculty of Mathematics and Natural Sciences,

Universitas Gadjah Mada, Yogyakarta, Indonesia

a)


[email protected]

Abstract. Gunung Mujil is an isolated hill located near Pondoworejo village, Kalibawang sub-district, Kulon Progo

district, and Special Province of Yogyakarta. The hill is part of the eastern Kulon Progo mountain range extended

relatively in the North-South direction. The lithology of the hill consists of andesite breccia and it’s similar with the

Old Andesite Formation that built the Kulon Progo Mountains. There are at least two hypothesis about the genesis

and the formation mechanism of this hill, (1) it was formed by an intrusion and (2) from the debris mass of Kulon

Progo Mountains. Our study intended to determine the subsurface resistivity below the hill and to relating those

results to with the scenario of the genesis of the Mujil hill. We conducted Audio magnetotellurics (AMT)

measurements along two lines survey crossing the Mujil hill consisting of 20 measurements. Since the measurements

are located near the villages, most of the data has a fair to bad quality and only one station yielded an excellent data.

A 1D Forward modeling was then applied to find best-fit model of the AMT data. The results shows that the Mujil

hill was built by debris mass of the Old Andesite Formation from Kulon Progo mountain which is represented by a

lower resistivity value under the Mujil hill.

EV-15

EV-16





59

Use of Electrical Geophysical Methods for Supporting

Agricultural Practices

Iqbal F. Aditama a)

, Widodo

b), Tedy Setiawan,

Satria Bijaksana, and Teuku A.

Sanny

Geophysical Engineering Department, Bandung Institute of Technology, Bandung, Indonesia.

a)


[email protected]

Abstract. Geophysical methods have been increasingly popular for shallow and environmental studies in the

worldwide. In particular an electrical geophysics method is helpful in soil a investigation which is focused on an

interval from ground surface down to a depth of 2 meters. The instrument of electrical geophysics were developed

and successfully applied to assist in precision agricultural practices in the worldwide, i.e. Russia and USA. Our

group from Indonesia has developed a geophysical instrument that integrated with agricultural machinery to

measuring electrical resistivity, conductivity, and potential that can be used for mapping agricultural production

fields. In addition, we created a forward modelling for help us to understand detection limits of our target.

Innovation for Soil Studies with Electromagnetic

Induction Techniques

Iqbal F. Aditama a)

, Widodo

b), Tedy Setiawan,

Satria Bijaksana, and Teuku A.

Sanny

Geophysical Engineering Department, Bandung Institute of Technology, Bandung, Indonesia.

a)


[email protected]

Abstract. Electromagnetic methods for soil research have been applied in the worldwide over the decades. In

particular Electromagnetic induction (EMI) techniques have been developed to provide more accurately soil maps.

Present EMI methods can identify, characterize, and map spatially-varying soil types and properties offers better

than traditional methods. In the future, the EMI techniques will be integrated with agricultural machinery and will be

more effective to mapping of both lateral and vertical variations in soil properties. With that advantages, the systems

should be utilized in precision agriculture more often in Indonesia. In addition, forward modelling also included in

this research as a survey design tool before the outset of field campaign.

EV-17

EV-18

60

Applied EM and Resistivity methods for near surface

Investigation Arround Unpad Jatinangor

Asep Harja, Dini Fitriani, and Bambang Wijatmoko

Geophysics Department, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran,

Jl. Bandung-Jatinangor km. 21, Jatinangor 45363, Indonesia.


Abstract. Using inductive and galvanic resistivity of geophysical methods for mapping near surface and knowing

qualitatively of soil fertility have applied in Unpad campus area. First is inductive method of Horizontal Coplanar

(HCP). This equipment is used one of geometry of electromagnetic induction methods in which consist of two coils,

as transmitter and receiver. Using of 10 KHz frequency, ability of this can measure variation of apparent

conductivity six to nine meters in depth for suitable of near surface investigation. Second is galvanic methods of

DC-Resisitivity and IP used for mapping and sounding the structure of the shallow subsurface of sediment, rock and

mineralization. Based on ions in the soil, conductivity value can be used for identify of soil fertility. More

conductive soil indicates that soil contains more in as plant nutrients. In this research, we have carried out

conductivity measurement at farms and plantations campus Jatinangor and complimented by pH measurement of the

soil. The results shows that the conductivity value in this area is quite low. It indicate that high conductivity values

correlated with high nutrient content and pH less than 7. The results based on analysis of this soil conductivity

values with the pH value and nutrient content required for the plant. Conductivity values obtained in the study is low

and correlated with nutrient content are quite low and below a neutral pH. Topography slope of this investigation

area is suspected as cause the displacement of the fertile soil layer from high to lower topography by flow of water

when it rains (water run-off). The results of the analysis of conductivity value and nutrient content of the soil showed

that investigation area is susceptible to ground motion when water saturated and dry condition.

EV-19

61

Code Paper Title

EG-01 Underground Infrastructure Detection Using Ground Penetrating Radar

Method

EG-02 Quality Investigation of Building Structure Using Ground Penetrating

Radar Method which is Effective and Environmentally Friendly as an

Early Study to Prevent Severe Structural Damage

EG-03 Interpretation of VLF-EM & VLF-R Data Using Tipper and Impedance

Analyses: a Case Study from Candi Umbul-Telomoyo, Magelang,

Indonesia

EG-04 VLF-EM and VLF-R Modelling Using 2layinv and Karous-Hjelt

MATLAB in Candi Umbul Magelang Indonesia

EG-05 Magnetic Data Analysis to Determine the Subsurface Structures in Candi

Umbul Geothermal Prospect Area, Central Java

EG-06 Identification and Monitoring of Subsurface Structure of Tunnel Using

Electromagnetic Method

EG-07 Time Domain Electromagnetic Survey for Geotechnical Exploration at

Singa Substation

EG-08 Utilizing of 2-D Resistivity with Geotechnical Method for Sediment

Mapping in Sungai Batu, Kedah

EG-09 Subsurface Imaging using Electrical Resistivity Imaging and

Geotechnical Engineering Methods in Penang, Malaysia

EG-10 Analyzing Soil Electrical and Strength Parameters Using Geophysical and

Geotechnical Methods in Sungai Batu, Kedah

EG-11 Identifying Causative Factors of Mass Movements in Terengganu,

Malaysia via 2-D Electrical Resistivity

EG-12 Detection of Underground Voids in Tahura Japan Cave Bandung Using

Ground Penetrating radar

EG-13 Underground Utility Mapping Using Multi Frequency Ground Penetrating

Radar Method in Muara Karang Power Plant, Jakarta, Indonesia

EG-14 Application of Geosciences Parameters in Identifying Rock Properties at

Bukit Chondong, Malaysia

EG-15 Analysis of Earthquake-Resistant Buildings in Palu City Based on

Microtremor Measurement

EG-16 Detection of Underground High-Voltage Electrical Cable in Urban Area

EG-17 Simulation of Earthquake-Induced Landslide in West Java, Indonesia:

Geometry and Its Geoelectrical Responses

62

Underground Infrastructure Detection Using Ground

Penetrating Radar Method

Rahmat Fajri, Amajid Sinar, Kevin Hartono, Indriani Yunitasari, and Widodo

Geophysical Engineering, Faculty of Mining and Petroleum Engineering, Institute of Technology Bandung,

Ganesa st. Indonesia


[email protected]

Abstract. State development in Indonesia heavily damaged the old underground infrastructure such as pipes and

cables. Incomplete analysis of initial conditions caused high cost and a fairly long process. The study aimed to find

innovative use of Ground Penetrating Radar (GPR) as one of geophysical methods to detect underground

infrastructure, which in this context is the underground piping at ITB, Ganesha. We used ReflexW to model the

subsurface containing the soil, asphalt, and the steel pipes itself. The contrast shown in radargram were interpreted

as the difference of electrical property below the surface. The detected anomalies below the planned area were cross-

checked with the ITB pipeline blueprint as the reference to determine the existence of pipeline. We found expected

anomalies with the diameter of 30-50 cm at half meter below the surface. Further research is needed to detect

underground infrastructure other than pipelines.

Quality Investigation of Building Structure Using Ground

Penetrating Radar Method which is Effective and

Environmentally Friendly as an Early Study to Prevent

Severe Structural Damage

M Fariz Gumai1, Stephen Fernando

1, Gatot Nugroho

1, Kana Natania

1, and

Widodo2


1Program Studi Teknik Geofisika – Institut Teknologi Bandung, Jl. Ganesha No. 10 Bandung 40132.

2KK Geofisika Terapan – Fakultas Teknik Pertambangan dan Perminyakan – Institut Teknologi Bandung, Jl.

Ganesha No. 10 Bandung 40132.

Abstract. Many infrastructures in Indonesia suffered damage in a short period of time. It proves that there are still

many buildings in Indonesia which have questionable quality so we need a method for checking the quality of the

building. Ground Penetrating Radar (GPR) is a method used to describe the structure of the building on the inside

that cannot be seen from the outside in this case we examined PASAGA bridge with 19,7 m X 3,3 m X 1,5 m

dimension. This method uses propagation of electromagnetic wave, which will give Radargram response inside a

building based on the characteristics of the medium such as magnetic permeability, electric permittivity and

electrical conductivity. GPR method is one of geophysical method which is effective, efficient, and environmentally

friendly. From this study, we found indications of fracture at less than 1 m depth in the structure from the Radargram

display of PASAGA Bridge and supported by the observation data on the surface.

EG-01

EG-02


63

Interpretation of VLF-EM & VLF-R Data Using Tipper

and Impedance Analyses: a Case Study from Candi

Umbul-Telomoyo, Magelang, Indonesia

Erina Prastyani1, a)




a)


[email protected]

Abstract. The goal of all geophysical survey techniques is to image the properties of the Earth’s subsurface. Very

Low Frequency (VLF) is one of the geophysical survey technique that has been commonly used for ore exploration

and mapping faults or fracture zones. Faults or fracture zones are necessary components in providing the fluid

pathway in geothermal systems. The Candi Umbul-Telomoyo is one of the geothermal prospect sites in Indonesia,

which is located in Magelang, Central Java. Recent studies hypothesized that this site was an outflow area of

Telomoyo volcano geothermal complex. We used the VLF-EM and VLF-R techniques to infer faults or fracture

zones that might be a path for geothermal fluids in the Candi Umbul-Telomoyo. From the measurements, we got tilt

angle and ellipticity for VLF-EM data; and apparent resistivity and phase angle for VLF-R data. To interpret the

data, we used tipper and impedance analyses. The result of both analyses show similarities in the directions and

positions of anomalous conductive features which were assumed as faults or fracture zones. The inferred structures,

from the data analyses could be geothermal fluids pathways upward to the surface. We are still doing this research in

order to obtain quantitative results of the conductive anomalies.

VLF-EM and VLF-R Modelling Using 2layinv and

Karous-Hjelt MATLAB in Candi Umbul Magelang

Indonesia

Adella Putri Affanti1, a)




a)


[email protected]

Abstract. A research for geothermal energy is increased due to the need of green energy. The presence of

geothermal manifestations indicate the existence of geothermal system. One of the geothermal manifestations is

warm spring. Candi Umbul area which located in Telomoyo, Magelang has warm spring as the geothermal

manifestation. Very Low Frequency (VLF) is one of geophysical method that can be used to map the subsurface in

Candi Umbul, Telomoyo. VLF is a method using electromagnetic field that powered and transferred by the

transmitter. The receiver read the electromagnetic signal which induce the rock and give information about the

conductivity as the physical property measurred. In this research, after collecting and processing data, we modelled

VLF-EM and VLF-R data to explain the geothermal system of Candi Umbul. The modelling was conducted using

2layinv and Karous-Hjelt MATLAB. Both VLF-EM and VLF-R model were correlated for the interpretation. The

model showed an anomalous conductive feature beneath the research area. The result of this research showed that

the anomaly is oriented in NW-SE direction. This direction is assumed as a fluid path way of Candi Umbul which

become the outflow of Telomoyo geothermal system. To prove the early deduction this research is still on going.

EG-03

EG-04





64

Magnetic Data Analysis to Determine the Subsurface

Structures in Candi Umbul Geothermal Prospect Area,

Central Java

Puspita Dian Maghfira1, a)

and Sintia Windhi Niasari 1, b)

1Geophysics Sub-Departement, Faculty of Mathematical and Natural Sciences, Universitas Gadjah Mada.

a)


[email protected]

Abstract. Candi Umbul is one of the manifestation locations in Telomoyo geothermal prospect area. This

manifestation is warm spring which assumed as outflow. A magnetic study had been conducted in a geothermal

prospect area in Candi Umbul, Telomoyo, Central Java. Magnetic method is one of the geophysical methods used to

geothermal exploration. Magnetic method measures in the Earth’s magnetic field. The purpose of this research has to

map the susceptibility distribution in the subsurface due to the geothermal system. Proton Precession Magnetometer

(PPM) was used to measure the magnetic field. Data processing started from correcting magnetic data with diurnal

and IGRF correction, to achieve the total anomaly magnetic field. Then, the total anomaly magnetic field was

reduced to pole and to pseudo gravitation. For the qualitative interpretation, we used the result of the horizontal

gradient measurement, while the quantitative interpretation, we used 2D forward modelling. The 2D forward

modelling was conducted to produce the magnetic anomaly modelling with using mag2DC for windows. The result

of the quantitative interpretation is the horizontal position of the body due to the anomaly which is located close to

the Candi Umbul warm spring. This warm spring was controlled by fault which is the weak zone in this area, so the

hot water can easily passed from Telomoyo geothermal reservoir. The research is still ongoing to support the

conclusion of qualitative interpretation.

Identification and Monitoring of Subsurface Structure of

Tunnel Using Electromagnetic Method

Nadia Amalia1, M. Husaini

1, Ngurah Ade Kalyana

1, Probo Mukti Nugroho

1,

Widodo2

1Bachelor Program of Geophysical Engineering, Institut Teknologi Bandung

2Applied Geophysics and Exploration, Institut Teknologi Bandung


[email protected]

Abstract. Since ITB-Saraga tunnel was built in 1997, there was no such a monitoring ever took to investigate the

internal structure. In contrast, the information of internal structure is needed to identify the self-defect of tunnel

caused by the active traffic on the upside of tunnel. The aim of this survey is to identify and monitor the internal

structure of ITB-Saraga tunnel using Ground Penetrating Radar (GPR). GPR is chosen because it can detect defects

of tunnel using electromagnetic wave which is showed in the existence of contrast anomalies of magnetic

permeability, dielectric constant, and resistivity. To fulfil the requirements, acquisition along the surface, processing

and interpretation data, and analysing the results are necessary. The 100 MHz antenna is chosen from forward

modelling, and sampling rate value is 850 MHz with trace interval 0.1 meter. The data then is processed with

ReflexW software. The result is radargrams that shows the upper structure of the tunnel (0-8.5 meters), and further

analysis could give more detailed structures, even the self-defect tunnel itself. The results can be used as additional

information to minimize the casualties if disaster occurs.

EG-05

EG-06


65

Time Domain Electromagnetic Survey for Geotechnical

Exploration at Singa Substation

Sirelkhatim H. Mukhtar

Geophysicist, Director of Majussat Geosciences

[email protected]

Abstract. In 2008 the National Electric Corporation NEC in Sudan built an electric substation near Singa town in

the Blue Nile province in Sudan, the location is flat clay surface. Sandy slab was laid to construct the structure on

top of it. When they start building the concrete foundation of the steel towers groundwater accumulates around the

foundation. INEC recommend us to find the source of groundwater and suggest a solution for their problem, since

the water leak is very shallow we carried out 125 high resolution Time Domain Electromagnetic soundings, because

the substation is all metal structure we run our survey around the substation in a pattern so as to capture any buried

channel or water bearing sand lenses within the area. The survey was carried out using Geonics Protem system; it is

composed of digital receiver Protem 58 with air core receiver coil and high resolution time domain transmitter

Protem 47 energizing a 10x10 single turn loop, the loop-loop geometry configuration was used with offset of 15m

center to center, the measurement was carried in single frequency sweep: Ultra high frequency 273.5 Hz. The total

time span for this frequency starts from 0.035 millisecond to 3 milliseconds, soundings are spaced at 15m interval.

Due to large amount of data, Occam inversion was applied to generate smooth resistivity model, smooth models are

used to construct layered seed models for automatic inversion. Results of modeling is used to construct geo-electric

sections which reveals water saturated sandy layer overlain by 20-25 m of clay layer partially saturated with water

with 2-4m dry clay on top, as a result of NEC construction and the resulting load the water is squeezed from the clay

into the sandy slab on top which cause the foundations problem.

Utilizing of 2-D Resistivity with Geotechnical Method for

Sediment Mapping in Sungai Batu, Kedah

Z. M. Taqiuddin1, a)

, S. Rosli1, b)

, M. M. Nordiana1, c)

, I. N. Azwin1, d)

, and S.

Mokhtar2, e)

1Geophysics Section, School of Physics, 11800 Universiti Sains Malaysia, Penang, Malaysia.

2 Centre for Global Archaeological Research Malaysia, 11800 Universiti Sains Malaysia, Penang, Malaysia

a)


b)[email protected]

c)[email protected]

d)[email protected]

e)[email protected]

Abstract. Sungai Batu is Bujang Valley subdistrict, located at northern region of Peninsular Malaysia, recognized as

an international cultural and commercial crossroad for 2000 years ago, and recorded as the oldest archaeological site

in southeast Asia. The discoverer of iron smelting area (1st-4th century) shows the evidence of important iron

industry in Malay Peninsula to others civilization. Nowadays, a lot of interdisciplinary research were conducted in

this area including geophysical prospect to understand the subsurface profile for this locality. Geophysical approach

such as 2-D resistivity was performed with the main objective is to identify sediment deposit for this area. Four 2-D

resistivity survey lines were design acrossing borehole and data acquired using of ABEM SAS4000 system with

Pole-dipole array using 2.5 m minimum electrode spacing. The data obtained was process using Res2Dinv software

to produce inversion model and Surfer10 software used for interpretation and correlation with respective borehole

record. The 2-D resistivity inversion model shows that, the area dominated by clay soil with resistivity values of <50

Ωm while high resistivity values of >500 Ωm interpreted as hard layer. The saturated zone (<100 Ωm) were

identified at depth of >25 m which consider large volume of soil deposit during sedimentation process. The

correlation with the borehole recorded shows that clay profile distributed at depth >20 m. The present of shale in

certain borehole record indicate that the environment deposit is clam/stagnant water condition during the formation

process which suspected controlled by the deposition process from the land deposit.

EG-07

EG-08


66

Subsurface Imaging using Electrical Resistivity Imaging

and Geotechnical Engineering Methods in Penang,

Malaysia

Andy Anderson Bery1, M. M. Mordiana

1, Y. C. Kiu

1, M. K. A. Nur Amalina

1,

M. Saidin2, A. Mohamamad-Afiq

1, and A. M. Nur-Amalina

1

1School of Physics, Universiti Sains Malaysia, 11800 Penang, Malaysia

2Centre for Global Archaeological Research, Universiti Sains Malaysia, 11800 Penang, Malaysia


Abstract. There have been improvement in the subsurface investigation using non-destructive geophysical method.

These were supported by improvement in data inversion method for 2-D imaging method. This geophysical method

have been used for many environmental and engineering studies, such as slope monitoring, cavities detection, buried

man-made structures and so on. This paper present the 2-D data inversion in electrical resistivity method which was

carried out in Penang, Malaysia. This non-destructive method is used to image the subsurface for soil’s lithology

purpose. In addition, two inline boreholes were used to validate and verify the obtained results of electrical

resistivity imaging. Based on the electrical resistivity imaging, the subsurface is made up of four type of materials.

They are sandy silt, silty sand, sand and lastly weathered granite. Sandy silt and silty sand soils give resistivity

values of 200-300 Ω.m and 200-700 Ω.m. Meanwhile for sand and weathered granite materials, their resistivity

values are 400-800 Ω.m and 2800-3400 Ω.m respectively. Beside than electrical resistivity imaging, this work also

present the distribution of conductivity for the investigated subsurface via the 2-D conductivity model. In

conclusion, the used of the non-destructive geophysical method in this study is successful in image the investigated

subsurface lithology and the investigation coverage area is enhanced instead of information from two discrete points

of the geotechnical boreholes. Therefore, the integration of these two technical methods is capable and reliable to

give information about the Earth’s subsurface lithology.

Analyzing Soil Electrical and Strength Parameters Using

Geophysical and Geotechnical Methods in Sungai Batu,

Kedah

S Nabila1, M M Nordiana

1, I N Azwin

1 and Mokhtar Saidin

2

1School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia.

2Centre for Global Archaeological Research Malaysia, 11800 USM, Penang, Malysia.


Abstract. Engineering structures require strong foundations to prevent hazards occur due to lack of understanding

the subsurface soil. Geophysical and geotechnical surveys were conducted in Sungai Batu, Kedah to determine the

effectiveness of correlating electrical parameters for vertical resolution and to evaluate soil strength by integrating

Electrical Resistivity Tomography (ERT), Ground Penetrating Radar (GPR) and Standard Penetration Test (SPT).

Results from ERT and GPR showed heterogeneity in the subsurface stratigraphy from surface to 8.6 m depth. The

inversion model showed two zones of saturated (<150 Ωm) and dry zone (>150 Ωm). The integration of ERT, GPR

and SPT is applied at the borehole position which is at distance of 9.5 m of the survey line. The resistivity values at

distance of 9.5 m range from 7 – 30 Ωm due to soil formed by sedimentation originated from fluvial system (sandy

clay and clay). Calculated electrical conductivity values from GPR radargram coincide and in range with values

from ERT. At distance of 9.5 m, the electrical conductivity range from 32 – 148 mS/m. The N-value from SPT

showed low value with range of 12 – 20. The correlation of electrical parameters from ERT and GPR showed good

agreement which is effective for vertical resolution. Low resistivity (high conductivity), low N-value and

heterogeneity of the soil denote unstable subsurface. Sandy clay/clay in Sungai Batu are detrimental for shallow

foundation as the soil material is susceptible to subsidence and has irregular characteristics influenced by the

weather. Hence, the soils up to 8 m depth were unstable, weak and may cause harm to building structure.

EG-09

EG-10

67

Identifying Causative Factors of Mass Movements in

Terengganu, Malaysia via 2-D Electrical Resistivity

Nur Azwin Ismail1, a)

, Muhamad Iqbal Mubarak Faharul Azman1, b)

, Azim Hilmy

Mohd Yusof 1, c)


1Geophysics Section, School of Physics, Universiti Sains Malaysia, 11800 USM, Pulau Pinang, Malaysia

2Department of Geology, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia

a)




[email protected]

Abstract. The creeping of soils and mass movement often related with the unstable soil condition along the slope

area. The presence of boulders embedded within the subsurface and saturated zones have high potential to trigger the

mass movement. This study evaluates and identifies the causative factors of mass movements in Terengganu,

Malaysia by injecting current into the ground to map the subsurface of the study area. Nine 2-D electrical resistivity

survey lines were performed with 2.5m electrode spacing, giving the total length for each line is 100m. Terrameter

ABEM SAS 4000 system were used with Pole-dipole electrode configuration. Results indicate that the whole study

area is fractured metasediment shale bedrock with resistivity value of > 5000 Ωm covered with colluviums layer

with thickness and resistivity value of < 5m and 1500-3000 Ωm respectively. There are also presence of weathered

boulders are detected scattered near surface of study area with resistivity value >5000 Ωm. Saturated zones with low

resistivity value of <100 Ωm are also identified tabulated at the center of each model resistivity section as the survey

lines crossed the trough at 50m. Saturated zones and presence of weathered boulders within the subsurface are

identified as the two main causative factors of mass movement in this study area. They have potential to create the

unstable soil condition and induce slope failure and it should be taken into consideration for future development

works.

Detection of Underground Voids in Tahura Japan Cave

Bandung Using Ground Penetrating radar

Azizatun Azimmah1, a)

and Widodo2)

1Undergraduate Program of Geophysical Engineering, Institut Teknologi Bandung,

Basic Science Center-B Building, 2nd

Floor,

Ganesha St. No. 10, 40132, Bandung, Indonesia 2Lecturer of Geophysical Engineering, Institut Teknologi Bandung.

a)


[email protected]

Abstract. The detection of underground voids is important due to their effects on subsidence higher risk. Ground

Penetrating radar is one of geophysical electromagnetic methods that has been proven to be able to detect and locate

any void beneath the surface effectively at a shallow depth. This method uses the contrasts of dielectric properties,

resistivity and magnetic permeability to investigate and map what lies beneath the surface. Hence, this research

focused on how GPR could be applied for detecting underground voids in the site of investigation, The Japan Cave

in Taman Hutan Raya located in Dago, Bandung, Indonesia. We used 100 MHz GPR shielded antenna frequency

with three >80 meters long measurement lines. The result showed a different amplitude region which is proven to be

the air-filled cavities.

EG-11

EG-12

68

Underground Utility Mapping Using Multi Frequency

Ground Penetrating Radar Method in Muara Karang

Power Plant, Jakarta, Indonesia

Apulina Priskaa)

and Wahyudi W Parnadib)

Applied and Exploration Research Group, Department of Geophysical Engineering, Faculty of Mining &

Petroleum Engineering, Institut Teknologi Bandung, Jalan Ganeca 10, Bandung 40132 Indonesia

a)


[email protected]

Abstract. Ground penetrating radar (GPR) has proven as a nondestructive geophysical method that capable to give

information about the presence, location, and depth of buried object. For mapping underground conditions of vital

power plant like Muara Karang Power Plant, a nondestructive geophysical method was needed so that the power

plant activity could work normally during the mapping activity. In this paper, GPR method was used to map

underground utility condition below Muara Karang Power Plant. Multi frequency GPR method was used to give

better information about the underground condition. Using 100 MHz and 250 MHz GPR shielded antenna from

RAMAC system with CRP method survey, the underground utility mapping was performed to detect the type of pipe

network according to the pipes size. Data acquisition for this survey was performed on about 100 profile lines, with

but this paper only shows three sample profiles to show the difference of each pipe networks available in this

location. The radargram from each frequency is taken on same profile line and then combined as a composite image

using radargram combination technique by modifying the radargram using matGPR and Matlab code. Those

composite radargrams then processed using ReflexW software by applying static correction, dewow, frequency gain,

bandpass butterworth filter, background removal, and f-k filter. Composite radargram datasets were interpreted as

the overview estimation of underground utility condition of Muara Karang Power Plant. The radargram profile can

show the pipelines below Muara Karang Power Plant, with their diameter varies between 15 until 200 centimeters,

which classified as water network pipelines, gas network pipelines, and waste pipe network according to their

diameter.

Application of Geosciences Parameters in Identifying

Rock Properties at Bukit Chondong, Malaysia

A. N. Nordiana, M. M. Nordiana, and Teoh Ying Jia

School of Physics, 11800, Universiti Sains Malaysia, Penang, Malaysia.


Abstract. Rock is a naturally occurring substance. The study of rock properties and its mineral composition have

many useful information and benefits, such as for building construction and aggregates. Understanding of how rock

material was formed will reveal how it can be used in a building, its limitations and how it will weathered over time.

The research objectives are to categorize the rock properties based from the methods of geophysics, geotechnical and

petrography analysis, and to identify the possibility of the material used for construction purpose. The location of the

study is at Bukit Chondong, Beseri, Perlis, Malaysia. The study was conducted using 2-D Resistivity method,

geotechnical test and thin section analysis. For 2-D Resistivity method, the length of a single survey line is 40 m

with minimum of 1 m electrode spacing and the array used was Pole Dipole. For geotechnical test, there are two test

conducted on the core samples of mudstone and sandstone, which are permeability test and porosity test. Finally, the

core samples was analysed from thin section to observe the shape and sorting of the grains. The result was tabulated,

where sandstone has high conductivity compare with mudstone, which in the range of 8.6 to 70.0 mS/m and 3.2 to

8.0 mS/m respectively. The value of permeability for sandstone is high compare with mudstone, which is 4.48 and

0.883 (x10-22 m2) respectively. However, sandstone has low porosity of (0.9 %) compare with mudstone with

percentage of (1.6 %). By comparing both types of rocks in this area, sandstone has high conductivity, high

permeability and low porosity, while mudstone has low conductivity, low permeability and high porosity giving

sandstone and mudstone are suitable material for construction and aggregates. The methods of geophysics,

geotechnical and petrography analysis successfully identify the rock properties.

EG-13

EG-14

69

Analysis of Earthquake-Resistant Buildings in Palu City

Based on Microtremor Measurement

Mauludin Kurniawan1, Muhammad Rusli M.

2, and Muhammad Rusydi H.

2

1Tadulako Geoexploration Services, Palu, Central Sulawesi

2Physics Departement, Faculty of Mathematics and Natural Sciences, Tadulako University


Abstract. Palu-Koro Fault is one of active faults in Indonesia. The presence of of this fault caused high seismic

activity in the Palu city. The high seismic activity in Palu City should be accompanied with infrastructure based

earthquake resistant and appropriate regulatory risk reduction. infrastructure based on Earthquake resistant building

is an asset long-term government in sustainable development in the Palu city. This study aimed to find out the

suitability of public facilities in Palu city based SNI 03-1726-2012 in earthquake resistant building. Sample that be

used in this research is public fasility buildings, such as : school, government building, hospital, market, and hotel.

This daata aacquisition is done by recording the microtremor data on those buildings. Microtremor data Analysis

used Horizontal to Vertical Spectrum Ratio (HVSR) method to know natural frequency value of building. This

research result show that the building public facility that be used as sampled measurement, 70.6% of the sample

buildings do not SNI qualify and only 29.4% of buildings is eligible SNI earthquake resistant buildings.

Detection of Underground High-Voltage Electrical Cable

in Urban Area

Wahyudi W Parnadi1, a)

, Rizandi G Parnadi2, b)

, and Apulina Priska1,c)

1 Applied and Exploration Research Group, Department of Geophysical Engineering, Faculty of Mining &

Petroleum Engineering, Institut Teknologi Bandung, Jalan Ganeca 10, Bandung 40132 Indonesia 2Department of Physics, Faculty of Mathematics & Natural Sciences, Institut Teknologi Bandung, Jalan Ganeca

10, Bandung 40132 Indonesia

a)

Corresponding author: [email protected] b) [email protected]

c) [email protected]

Abstract. High-voltage electrical cable buried underground is a dangerous object for workers during man-made

construction at all building construction site if its location is unknown. Detecting and locating its existence is

therefore a very important priority activity prior to building construction. In this paper we report our effort in

detecting and locating a 150kV electrical cable at a project site for high rise building construction in Jalan Gatot

Subroto, Jakarta, Indonesia.. Due to high potential risk to work at site, we conducted Ground-penetrating Radar

(GPR) and Induced Polarisation (IP) measurements at that site. GPR measurement was carried out using RAMAC

system with 100MHz and 200MHz antenna on two 50m long profiles each frequency, whilst IP measurement was

conducted with 4 light HP IP system from Lipmann on ten 25m long profiles around GPR profiles. The Acquired

data were processed using conventional processing flow including dewow, bandpass filtering and f-k filtering. In

interpretation phase, we conducted simulation to calculate theoretically GPR response due to noise resulting from

high frequency electromagnetic wave source generated in subsurface and then proposed a method to remove such a

noise from radargram. Using such a method to reduce the influence of electrical cables locating at subsurface, we are

able to locate and detect electrical cable needed by geotechnical as well as civil engineer to plan and construct

reinforcement bar with a distinct distance from the high voltage electrical cable.

EG-15

EG-16


70

Simulation of Earthquake-Induced Landslide in West

Java, Indonesia: Geometry and Its Geoelectrical

Responses

Wahyudi W Parnadi1, a)

and Rizandi G Parnadi2, b)

1 Applied and Exploration Research Group, Department of Geophysical Engineering, Faculty of Mining &

Petroleum Engineering, Institut Teknologi Bandung, Jalan Ganeca 10, Bandung 40132 Indonesia 2Department of Physics, Faculty of Mathematics & Natural Sciences, Institut Teknologi Bandung, Jalan Ganeca

10, Bandung 40132 Indonesia

a)

Corresponding author: [email protected] b) [email protected]

Abstract. There are many landslide occurrence in Indonesia every year, especially in months October – March

during rainy season. The occurrence of earthquake induced by earthquake in Indonesia is seldom, however its

influence for human life must be taking into account. The Mw 7.5 Padang earthquake is an earthquake that caused

significant damage including landslides in some villages in and around Padang City. More than 1,100 peoples were

killed and over 2,900 injured. Such earthquake-induced landslide occurred also in West Java, including Cililin

district area. We conducted simulation to generate earthquake-induced landslide using available data from that area.

First we built land profiles with slope and determined its landslide potential through its safety factor. Safety factor is

calculated with as well as without earthquake influence. Using the same geometry, we simulated its geoelectrical

response at surface to know the effect of landslide potential on geoelectrical response. Using results of both

simulations, we proposed a strategy to monitor a landslide potential on slope based on geoelectrical data combined

with soil physical properties data.

EG-17

71

Code Paper Title

TH-01 Lembang Fault Plane Identification using Electrical Resistivity

Tomography for Disaster Mitigation

TH-02 Imaging the Northern part of the Great Sumatran Fault system based on

2D Inversion of Magnetotelluric Determinant data

TH-03 Magnetotelluric Data Analysis in Cascadia Subduction Zone, USA

TH-04 Applications of the VLF induction method for Rapid Sumatran Fault

Identification in Leuser National Park, Aceh

TH-05 Geophysical image of the hydrothermal system of Merapi volcano

TH-06 Applying 2-D Resistivity Imaging and Ground Penetrating Radar (GPR)

Methods to Identify Infiltration of Water in the Ground Surface

TH-07 Application of 2-D Resistivity Imaging and Ground Penetrating Radar

(GPR) Methods in Detecting Cavities Regarding the Geohazard

Assessment

TH-08 The General Indications of An Impact Crater Using Integrated

Geophysical Methods

TH-09 Subsurface Structure Imaging of the Sembalun-Propok Area, West Nusa

Tenggara by Using the Audio-frequency Magnetotelluric Data

TH-10 Trilogy Possible Meteorite Impact Crater at Bukit Bunuh, Malaysia Using

2-D Electrical Resistivity Imaging

TH-11 Identification of Near-surface Fault Structure Using Radio

Magnetotelluric (RMT)

TH-12 Hydrothermal System of the Papandayan Volcano from Temperature,

Self-Potential (SP) and Geochemical Measurements

TH-13 Geological Control Function for Controlled Source Audio-frequency

Magnetotelurrics (CSAMT) Interpretation

TH-14 Identification of Fault Structure along Jakarta-Bandung High Speed Train

Railway by using CSAMT and Seismic Tomography Methods

TH-15 The AMT and Gravity Across the lithology limits in PraTertiary rock of

Kebumen (Central Java)

TH-16 Application of Time Domain Electromagnetic Method to Study Lembang

Fault, West Java

TH-17 Survey the Potency of Landslides in Lembang Fault using Resistivity

Tomography

TH-14

72

Lembang Fault Plane Identification using Electrical

Resistivity Tomography for Disaster Mitigation

Sevi Maulinadya, M. Lutfi Ramadhan, Nanda Wening F., David Pinehas, and

Widodo

Geophysical Engineering Department, Faculty of Mining and Petroleum Engineering, Institut Teknologi

Bandung

Jl. Ganesha No. 10, Kota Bandung, Jawa Barat, 40132


[email protected]

Abstract. Lembang Fault is an active fault lies from West to East located 10 kilometers in north of Bandung. It is a

normal fault that its foot wall raises 40-450 meters above the ground. Its location that is not so far from Bandung,

which is densely populated and frequently visited by tourists, makes Lembang Fault a threat if it becomes suddenly

active. Its movement can cause earthquakes or even landslides that can result in fatalities. Therefore, act of

mitigation is necessary, such as educating people about Lembang Fault and its potential to cause disaster. The

objective of this study is to find Lembang Fault plane below the surface with geo electrical mapping method and

vertical electrical sounding method around Ciwarega and The Peak, Lembang (west side of Lembang Fault). Both of

these methods are using electricity current to measure rock resistivity. Currents are injected to the ground and

potential differences are measured. According to Ohm’s Law, resistivity can be calculated so that resistivity

distribution can be obtained. In this study, high resistivity contrast is obtained; it is about 1400-5000 Ohm.m. This

resistivity contrast can be caused by lateral lithology difference resulted by fault existence. This proves that there is

actually a fault in Lembang that potentially cause disasters like earthquakes and landslides.

Imaging the Northern part of the Great Sumatran Fault

system based on 2D Inversion of Magnetotelluric

Determinant data

Nazli Ismail1, Muhammad Yanis

2, and Muyassir

3

1Graduate Program in Disaster Science, Syiah Kuala University

2Physics Department, Syiah Kuala University

2Department of Geophysical Engineering, Syiah Kuala University


Abstract. It has been conducted a study for interpretation of subsurface resistivity model by using magnetotellurics

data at Seulawah Agam geothermal area, Aceh Province. The data were acquired at 7 stations along 35 km length of

a profile directed in north-south accross Seulawah Agam volcano. There is no preliminary geoelectrical strike

information in the area. Therefore the determinant of apparent resistivitiy and phase in range of frequency of 2.34 –

320 Hz were inverted using 2D inversion of REBOCC code (Siripunvarapon and Egbert, 2000). The 2D inverted

model have been able to obtain conceptual model of the geothermal system in Selawah Agam volcano based on

electrical resistivity variation within the subsurface. The upper most layer with slightly low resistivity values (i.e.

<10 Ωm) is interpreted as clay cap layer. While the layer with resistivity values range in 10-100 Ωm is interpreted as

reservoir area. The recharge areas are located at the northern and the southern part of profile.

TH-01

TH-02


mailto:nazli.ismail@unsyiah

73

Magnetotelluric Data Analysis in Cascadia Subduction

Zone, USA

Selvi Misnia Irawati a)

, Dina Sari Handayanib)

, and Wahyu Kusdyantonoc)

Geophysics Study Program, Department of Physics, Universitas Gadjah Mada.

. a)


[email protected]

c)

[email protected]

Abstract. The Cascadia subduction zone is a subduction zone that extends 1,000 km long from Vancouver Island,

Canada to California, USA. This subduction zone is formed by the subduction of Juan de Fuca plate to the North

American plate and resulted in geological features such as Cascadia Volcanic Range in the west USA. Geophysical

mapping is needed to image the subduction in this zone. From previous geophyscial research of this area, a research

that focusing on data analysis have not been conducted yet. This research is aimed to analyze the magnetotelluric

data in Cascadia subduction zone using Swift skew, Bahr skew, polar diagram, and phase tensor. From this data

analysis, we make 1-D and 2-D modeling. Then, we interpolate the 2-D model to make 3-D model. Thus, we can

make interpretation from that model. The result showed that generally data in research area are dominated by 2-D

and 3-D character. Impedance skew values varied for each site (<0.12 and >0.12 for Bahr skew and <0.2 and >0.2

for Swift skew), indicating 1-D or 2-D and 3-D character. Polar diagram and phase tensor analysis indicated the data

are mostly 2-D and 3-D, and some 1-D data also exist. Specifically, the west part of the research area, which

represent the subduction zone, has 1-D and 2-D character data. Meanwhile, the east part of the research area, which

represent the Yellowstone plume, has 2-D and 3-D character data. This characteristic makes 1-D and 2-D model are

more identical in the west part rather than the east part. Based on this research, polar diagram is the analysis

parameter that easier to use and can provide the information of geoelectrical strike in research area.

Applications of the VLF induction method for Rapid

Sumatran Fault Identification in Leuser National Park,

Aceh

Irwandi, Marwan, Muksin

Syiah Kuala University

[email protected]

Abstract. Aceh is an area that is in the active region of the volcanic and tectonic, where are many mountain

formation, folds, and active fault. One of them is Leuser mountain system in Gayo Luwes, Aceh. In this research, we

used T-VLF (Very Low Frequency) to detect fault along street from Babah Rot – Blangkejeren – Pinding which is

pass the Sumatran Fault. Preliminary identification of fault location is getting from literature and morphological

patterns of data topography of SRTM (Shuttle Radar Topography Mission). According the location we conduct VLF

observation. We have measured three profiles with a length of 12-16 km. Profile 1 has fluctuation data due to its

location related to high iron deposition. Profile 2 shows the results very consistent with the fault Blangkejeren

location. While profile 3 shows Lokop-Kutacane fracture and demonstrate the topography correction. In general

VLF method highly affected by noise which is a consequence of passive electromagnetic measurements. In order to

improve VLF processing, we need to develop a method how to integrate between topographic correction and the

VLF data to achieve geological fault mapping.

TH-03

TH-04


74

Geophysical image of the hydrothermal system of Merapi volcano

S. Byrdina 1, 2,

, S. Friedel3, J. Vandemeulebrouck

1, A. Budi-Santoso

4, Suhari

5, W. Suryanto

5,

M.H. Rizal5, E. Winata

5, Kusdaryanto

5, and H. Grandis

6

1Universite de Savoie Mont Blanc, CNRS, ISTerre, F-73376 Le Bourget du Lac, France

2IRD, ISTerre, F-73376 Le Bourget du Lac, France

3Comsol Multiphysics GmbH, Technoparkstrasse 1, CH-8005 Zürich

4BPPTKG, Jl. Cendana No. 15, Yogyakarta 55166, Indonesia

5Gadjah Mada University, Yogyakarta, 55281, Indonesia

6Institut Teknologi Bandung, Jln. Ganesha 10, Bandung, 40132, Indonesia


Abstract. We present the hydrothermal system of Merapi volcano based on results from electrical resistivity

tomography (ERT), self-potential (SP) and CO2 flux mappings. The ERT models identify two distinct low resistivity

bodies interpreted as two parts of a probably interconnected hydrothermal system: at the base of the south flank and

in the summit area. In the summit area, a sharp resistivity contrast at ancient crater rim Pasar-Bubar separates a

conductive hydrothermal system (20-50 Ωm) from the resistive andesite lava flows and pyroclastic deposits (2,000-

50,000 Ωm). The existence of preferential fluid circulation along this ancient crater rim is also evidenced by SP data.

A significant diffuse CO2 degassing (with a median value of 400 g m−2 d−1) is observed in a narrow vicinity of the

active crater rim and close to Pasar-Bubar. The total CO2 degassing across the accessible summit area with a surface

of 1.4x105 m2 is around 20 t d−1, while it was higher (about 200-230 t d−1) before the 2010 eruption. This drop can be

related to the decrease in the magmatic activity, to the change of the summit morphology, to the approximations

used, or more likely, to a combination of these factors. On the south flank of Merapi, the resistivity model shows

spectacular stratification, i.e. superficial recent andesite lava flows characterized by resistivity exceeding 100,000

Ωm and resistivity as low as 10 Ωm at a depth of 200 m interpreted as a presence of the hydrothermal system. No

evidence of a hydrothermal system on the base of the north flank at the same depth. This asymmetry might be caused

by the asymmetry of the heat supply source of Merapi whose activity is moving south and/or to the asymmetry in

topography caused by the presence of Merbabu volcano in the north. We suggest that stratified pyroclastic deposits

on the south flank of Merapi screen and separate the flow of hydrothermal fluids with the gaseous part rising through

the crater rims, while the liquid part is flowing downwards to the base of the edifice.

Applying 2-D Resistivity Imaging and Ground Penetrating Radar

(GPR) Methods to Identify Infiltration of Water in the Ground

Surface

Azim Hilmy Mohamad Yusof1, a)

, Muhamad Iqbal Mubarak Faharul Azman1, b)

, Nur Azwin

Ismail1, c)


1Geophysics Department, School of Physics, 11800, Universiti Sains Malaysia, Penang, Malaysia.

2Department of Geology, Faculty of Science, Universiti Malaya, 50603, Kuala Lumpur, Malaysia.

a)




[email protected]

Abstract. Infiltration of water into the soil mostly happen in area near to the ocean or area where rain occur

frequently. This paper explains about the water infiltration process that occur vertically and horizontally at the

subsurface layer. Infiltration act as an indicator of the soil’s ability to allow water movement into and through the

soil profile. This research takes place at Teluk Kumbar, Pulau Pinang, an area that located near to the sea. Thus,

infiltration process occurs actively. The study area consists of unconsolidated marine clay, sand and gravel deposits.

Furthermore, the methods used for this research is 2-D Resistivity Imaging by using Wenner-Schlumberger array

with 2.5 m minimum electrode spacing, and the second method is Ground Penetrating Radar (GPR) with antenna

frequency of 250MHz. 2-D Resistivity Imaging is used to investigate the subsurface layer of the soil. Other than that,

this method can also be used to investigate the water infiltration that happen horizontally. GPR is used to investigate

shallow subsurface layer and to investigate the water infiltration from above. The results of inversion model of 2-D

Resistivity Imaging shows that the subsurface layer at distance of 0 m to 20 m are suspected to be salt water

intrusion zone due to the resistivity value of 0 Ω.m to 10 Ω.m. As for the radargram results from the GPR, the

anomaly seems to be blurry and unclear, and EM waves signal can only penetrate up to 1.5 m depth. This features

show that the subsurface layer is saturated with salt water. Applying 2-D resistivity imaging and GPR method were

implemented to each other in identifying infiltration of water in the ground surface.

TH-05

TH-06

75

Application of 2-D Resistivity Imaging and Ground

Penetrating Radar (GPR) Methods in Detecting Cavities

Regarding the Geohazard Assessment

Muhamad Afiq Saharudin, M.M Nordiana, and I.N Azwin

Geophysics Section, School of Physics, Universiti Sains Malaysia, 11800, Pulau Pinang.


Abstract. Karstic features such as voids or cavities are often a major engineering risk associated with construction in

areas underlain by carbonate rocks topography. This research was conducted to distinguish the geophysical

parameters indicating between two types of cavities which are the air-filled cavity and in-filled cavity. There is one

study area acts as the air-cavity model and two study areas act as the in-filled cavity model. All the study areas

located at Universiti Sains Malaysia (USM), Pulau Pinang. The other study area is at Bukit Kalong, Perlis in which

could represents the in-filled cavity that fill with sediments. The air-filled cavity will have a higher resistivity value

between 500 Ωm until 800 Ωm while the in-filled cavity will have lower resistivity value of 10 Ωm until 250 Ωm.

The result from Bukit Kalong is compared with both of the results that have been done at USM. A higher

conductivity value of 0.0909 S/m represents as the in-filled cavity while lower conductivity value of 0.0016 S/m

represents the air-filled cavity. The attenuation value of electromagnetic (EM) wave for in-filled cavity is higher

with 65.7074 dB/m while lower value is for air-filled cavity with 0.9901 dB/m. As for the GPR results the

hyperbolic patterns will be much clearer as for the air-filled cavity compared with the in-filled cavity due to the

difference of the dielectric permittivity. Based from geophysical parameters obtained from both of those geophysical

method used, Bukit Kalong study area was considered as in-filled cavities dominated as sediments-filled cavity.

The General Indications of An Impact Crater Using

Integrated Geophysical Methods

Y. C. KIU1, a)

, S. ROSLI1, b)

, I. N. Azwin1, c)

, and S. Mokhtar2, d)

1Geophysics Section, School of Physics, 11800 Universiti Sains Malaysia, Penang, Malaysia.

2Centre for Global Archaeological Research Malaysia, 11800, Universiti Sains Malaysia, Penang, Malaysia

a)

Corresponding author email’s: [email protected] b)



[email protected]

Abstract. The study area located at the tropical region which may induced a deeply eroded structure over a complex

subsurface. Therefore, the geophysical methods were applied to estimate crater dimension and study the signature of

an impact crater. Commonly, an impact crater is characterized with the aid of potential field method which can cover

larger area and cost effective. The application of seismic measurements is to complement the potential fields’

method for better data interpretation. This study emphasized on utilizing integrated study of geophysical methods

which include potential field method (ground magnetic) and seismic for bedrock delineation on impact crater

structure characterization. The results induced a positive signs of impact crater which associate with a few

indications on crater type and its structures. The integration of ground magnetic and seismic refraction reveal the

Bukit Bunuh impact crater is a complex crater at. Both of the geophysical methods agreed with the notable size

impact crater of 5 km with central uplift at the Bukit Bunuh area.

TH-07

TH-08



76

Subsurface Structure Imaging of the Sembalun-Propok

Area, West Nusa Tenggara by Using the Audio-frequency

Magnetotelluric Data

Febriani, F1, Widarto, D. S

2, Gaffar, E

3, Nasution, A

3, and Grandis, H

4

1Research Center for Physics, Indonesian Institute of Science (LIPI), Kawasan Puspiptek Bldg. 440-442

Serpong, Banten Indonesia, 15134 2Upstream Technology Center, PT Pertamina, Jakarta, Indonesia, 10110

3Research Center for Geotechnology, Indonesia Institute of Sciences (LIPI), Jln. Sangkuriang, Kompleks LIPI,

Bldg. 70, Bandung, Indonesia 40135 3Department of Geology Engineering, Bandung Institute of Technology (ITB), Bandung, Indonesia, 40132

4Department of Geophysical Engineering, Bandung Institute of Technology (ITB), Bandung, Indonesia, 40132


Abstract. We have investigated the subsurface structure of the Sembalun-Propok Area, West Nusa Tenggara, by

using the audio-frequency magnetotelluric (AMT) method. This area is one of the geothermal prospect areas in

eastern Indonesia. There are 38 AMT observation points, which were deployed along three profiles. We applied the

phase tensor analysis on all observation points to determine both the dimensionality of and the regional strike of the

study area. The results of the phase tensor analysis show that the study area can be assumed as 2-D and the regional

strike of the study area is about N330oE. Then, after rotating the impedance tensor data to the regional strike, we

carried out the 2-D inversion modeling to know more detail the subsurface structure of the study area. The results of

the 2-D MT inversion are consistent with the geology of the study area. The near surface along all profiles is

dominated by the higher resistivity layer (> 500 Ωm). It is highly associated with the surface geology of the study

area which is characterized by the volcanic rock and mostly consist of andesitic to dacitic rocks of a calc-alkaline

suite. Below the resistive layer at the near surface, the modelings show the layer which has the lower-moderate

resistivity layer. It is possibly a cap rock layer of geothermal system of the Sembalun-Propok area. Lastly, the third

layer is the very conductive layer and possibly associated with the presence of thermal fluids in the study area.

Trilogy Possible Meteorite Impact Crater at Bukit Bunuh,

Malaysia Using 2-D Electrical Resistivity Imaging

M. Jinmin1, a)

, S. Rosli1, b)

, M. M. Nordiana1, c)

, and S. Mokhtar 2, d)

1Geophysics Section, School of Physics, 11800 Universiti Sains Malaysia, Penang, Malaysia

2Centre for Global Archaeological Research Malaysia, 11800 Universiti Sains Malaysia, Penang, Malaysia

a)

Corresponding author email’s: [email protected] b)



[email protected]

Abstract. Bukit Bunuh situated in Lenggong (Perak) is one of Malaysia’s most important areas for archeology that

revealed many traces of Malaysia’s prehistory. Geophysical method especially 2-D resistivity imaging method is

non-destructive which applied in geo-subsurface study for meteorite impact. The study consists of two stages that are

regional and detail study which a total of fourteen survey lines. The survey lines were conducted using Pole-dipole

array with 5 m minimum electrode spacing. The result of each stage are correlated and combine to produce detail

subsurface resistivity distribution of the study area. It shows that the area consists of two main layers which are

overburden and granitic bedrock. The first layer is overburden mix with boulders with resistivity value of 10-800

Ωm while the second layer is granitic bedrock with resistivity value of >1500 Ωm. This study also shows few spotted

possibility of uplift (rebound) due to the high impact which suspected from meteorite. A lot of fracture were found

within the survey area which could be one of the effect of meteorite impact. The result suggest that Bukit Bunuh is

under layer by a complex crater with diameter of crater rim is approximately 5-6 km.

TH-09

TH-10

77

Identification of Near-surface Fault Structure Using Radio

Magnetotelluric (RMT)

Rifki Mega Saputraa) and Widodo

b)

1Geophysical Engineering, Institut Teknologi Bandung

Jalan Ganesha 10, Bandung, Indonesia, 40132

a)


[email protected]

Abstract. This study area of Mygdonian Basin in Northern Greece is one of the most active seismic zones in

Europe. It is the location where was affected by the largest recent earthquake in 1978 with magnitude 6.5. The

geology of this area consists four major unit, which are the lower terrace deposit, Holocene deposit, fans, and the

metamorphic. Measurement using RMT was intended to get a better understanding of the near-surface fault

structure. We used frequency ranges from 18.3 kHz to 864 kHz. Due to high frequency and high resistivity in the top

layer, the approximation of skin depth is about 35 meters. Data were collected along one profile which had 1,250

meters in length and 50 meters of each station distance, so the RMT soundings gave a total number of 26 data. Then,

the model is presented in 1D to know information between resistivity and depth. We also made the 2D model to gain

clear structures and interpret more easily. The result implies that near-surface fault structure can be defined from

RMT data.

Hydrothermal System of the Papandayan Volcano from

Temperature, Self-Potential (SP) and Geochemical

Measurements

Svetlana Byrdina1, 2 a)

and Hendra Grandis3, b)

André Revil1, Hendra Gunawan

4

and Ugan B. Saing4

1Université de Savoie Mont Blanc, Institut des Sciences de la Terre (ISTerre), Le Bourget du Lac, France

2Institut de Recherche pour le Développement (IRD), Le Bourget du Lac, France

3Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Indonesia

4Center for Volcanology and Geological Hazard Mitigation, Indonesia

a)


[email protected]

Abstract. Papandayan is an active volcano in West Java, Indonesia. The volcano is characterized by intense

hydrothermal activities manifested by numerous fumaroles at three craters, Kawah Mas, Kawah Manuk and Kawah

Baru. The latter was created after November 2002 phreatic eruption. Since 2011, numerous volcano-tectonic B

events are encountered and Papandayan volcano is set on alert status on several occasions. The purpose of the

present study is to delineate the structure of the summital hydrothermal system using the data of self-potential (SP),

soil temperature and gas concentrations in the soil (CO2, SO2 and H2S). This combination of geophysical and

geochemical methods allows identification of the weak permeable zones serving as preferential pathways for

hydrothermal circulation and potential candidates to future landslides or flank collapses. This study is an ongoing

collaborative research project and we plan to conduct geo-electrical measurements, i.e. electrical resistivity

tomography (ERT) and also Induced-Polarization (IP) surveys. Additional data would allow the 3D imaging of the

studied area. The IP parameters will be used to characterise and to quantify the degree of alteration of the volcanic

rocks as has been shown very recently in the laboratory studies by Revil (Revil, in prep.) There are also thirteen

rocks samples that will undergo laboratory analyses at ISTerre for IP and complex resistivity parameters at sample

scale that will help to interpret the survey results.

TH-11

TH-12

78

Geological Control Function for Controlled Source Audio-

frequency Magnetotelurrics (CSAMT) Interpretation

Teuku Abdullah Sanny

Geophysical Engineering, Faculty of Mining and Petroleum Engineering, Bandung Institute of Technology

[email protected]/[email protected]

Abstract. Surface geological mapping is one of important think to discribe evidently shows of how the earth

forming of generally geological process and structured by tectonics activity. Based on some of researcher from

geodetic investigation, the Lembang fault is active fault. So, the study of Lembang fault is important thing. The

objective of this study is to determine to interprate the correlation between surfrace Lembang Fault and the

subsurface fault. For detail study we use three methodologies: (1). Identification and mapping the fault structure

along surface deformation, (2). Considering the CSAMT image, and (3) Borehole identification, considering

simulation by using Boundary Element Methods (BEM). Based on the study by using geological mapping by using

Boundary Element Methods (BEM) that is the direction Lembang fault has dominant displacement in east direction.

The eastward displacement at the nothern fault block is smaller than the eastward displacement at the southern fault

block which indicates that each fault block move at left direction relative to each other. From this study we know

that Lembang fault in this area has left lateral strike slip component. The western part of the Lembang fault move in

west direction different with the eastern part that move in east direction. Stress distribution map of Lembang fault

shown has difference between the eastern and western segments of Lembang fault. Displacement distribution map

along x-direction and y-direction of Lembang fault shown a linement oriented in northeast-southwest direction right

on Tangkuban Perahu Mountain. Based on surface geological mapping that we know the characteristic of Lembang

fault as normal fault. Based on CSAMT method the lembang fault is not single normal fault but the structure are that

different of dip which formed as graben structure.

Identification of Fault Structure along Jakarta-Bandung

High Speed Train Railway by using CSAMT and Seismic

Tomography Methods

Teuku Abdullah Sanny

Geophysical Engineering, Faculty of Mining and Petroleum Engineering, Bandung Institute of Technology

[email protected]/[email protected]

Abstract. The interest of the study was to prove the existance of fault structure and geological contact along Jakarta-

Bandung High Speed Train Railways. Based on surface geological mapping with precences of outcrops can be

determined geological contact between layer rock and geological events like fold, crack, fault, and intrusion.

Controlled source Audio-frequency Magnetotelluric (CSAMT) is a geophysical investigation method to obtaining

subsurface resistivity values which related to critical information about lithology, weathering zone, geological

structure, and hidrogeology. By involves transmitting a controlled signal at a suite of frequencies into the ground

from one location of transmitter site and measuring the electric and magnetic fields by using the receiver in the

interest area which identified having fault structure. The ratios of orthogonal,, horizontal electric and magnetic field

magnitude are used to calculate the subsurface resistivity structure. For this study, distance suite of transmitter site

and receiver site are between 5-7 km. By using CSAMT method ha proven usefull for subsurface geological and

fault structure mapping in the 300 to 500m. For CSAMT interpretation of boundary layer of geology and fault

strucure we also considered from surface geological mapping and controled by borehole. Especially for

identification along the tunnel line we considered that using the refraction seismic tomography method dan seismic

crosshole tomography. Results from both methods were integrated to get data correlation. There are good correlation

produced which succesfully proved the existence of weathering zone, lithology, fold, crack, fault, and intrusion

along Jakarta-Bandung high speed train railway which will considered by civil engineers for construction of railway

throughout 147 km and 11 (eleven) of tunnel.

TH-13

TH-14

79

The AMT and Gravity Across the lithology limits in

PraTertiary rock of Kebumen (Central Java)

Agus Laesanpura1, Darharta Dahrin

1, and Asep Sugianto

2

1Institut Teknologi bandung

2Geology Developmbent Center


Abstract. The Kebumen in central java, is famous for Pretertiary rock of old subduction zone, hence rock variation

is very high, from sedimentary, metamorphic, and also igneous rock. The relationship between these rock on limited

zone such as the limestone, igneous, and Conglomeratic-clay of Karangsambung Formation is poor recognize in

subsurface. The current survey of gravity and AMT data is executing to delineate this boundary. The gravity profile

and four point AMT is measure for reconnaissance study. The field observations is also observable, but the soil is

prohibiting deep in detail. The general result show for the deep of one and half kilo meter, the gravity data cover

the mayor rock, but the AMT is more significance in better delineating the boundary. Hence the lithology could be

distinguished for mélange rock(1000 Ohm.m) and karangsambung Formation of clay-conglomerate(80 Ohm.m), but

also diabase of volcanic-plutonic rock (4000 Ohm.m). The preliminary result show the limestone spread-out on this

area is probably the olistolit, and the extensions is more pronounce that the surface observations only, the second

mysterious of diabase is more probably as sill product rather than dike.

Application of Time Domain Electromagnetic Method to

Study Lembang Fault, West Java

Faeruz Maulana Rasyid and Widodo

Geophysical Engineering, Institut Teknologi Bandung,

Basic Science Center-B Building, 2nd Floor,

Ganesha St. No. 10, 40132, Bandung, Indonesia


Abstract. Lembang Fault is an active fault structure exceeds populous area. It is located about 9 km of the city

centre of Bandung in the West Java. We conducted electromagnetic survey that involves area of the Lembang Fault

in the Karyawangi Village, West Bandung. Time domain electromagnetic (TDEM) measurements were carried out

on two profiles, with a total number of 34 soundings. The TDEM data gives detail information of the shallow

conductivity structure down to a depth of 100 m. The 1-D models consist of three layers in the research area. The

first layer in the depth between 0 to 3 meters is dominated by low resistivity (<10 Ωm) which associates with the top

soil, the second layer is tuff in the depth of 3 to 35 meters is represented by high resistivity ( > 100 Ωm). The third

layer with resistivity of 10 – 100 Ωm is corresponds to sandstone. The model indicates a local fault structure in the

study area.

TH-15

TH-16


80

Survey the Potency of Landslides in Lembang Fault using

Resistivity Tomography

Rianty Kusuma Dewia), Donny Satrio Mahartha, Kevin Hartono, Lidwina

Grasiani Kristi, and Widodob)

Geophysical Engineering, Bandung Institute of Technology, Ganesha St 10,. Indonesia.

a)

Correspondence author: [email protected] b)

[email protected]

Abstract. Lembang especially in Langensari Village has a big potency of landslides. This potency are arising

because the existence of the Lembang fault. Lembang fault has turf layer with a big value of dip more than 45⁰, high

rate of rainfall per year, has a big the potency of earthquakes, and the important thing in this area just have a little

vegetation which makes the landslides easily happened. The aim of this research are identification potency and cause

of the landslides in Langensari Village (District Lembang, Bandung Barat), identification the shape and

characteristics of the landslides, and mapping the area which has potency of landslides. The object of this research

are structure of the fault, layering of the rocks, and water content of the rocks. We used resistivity tomography

method for understanding the layering of the stones and water content of the soils. We used dipole-dipole

configuration and processing data and forward modelling with RES2DINV. The pseudo section shows the high

contrast of resistivity and high porosity in 8 meters under the surface, the rate of rainfall 2000-2500 mm/year, and

the movement of the fault is 3-5.5 mm/year. All of the result especially high contrast can be the indication of the

landslides in the next days.

TH-17


81

Code Paper Title

RM-01 Pollution Detected Innovation of The Hazardous and Toxic Substance

Disposal by Magnetic Susceptibility Method around Cikijing River,

Rancaekek for testing water quality standards

RM-02 Construction of an inexpensive field gradiometer based on FGM3-sensor

and SCL007 IC chip

RM-03 Magnetic Properties of Deposited Sediments in Surabaya River, East

Java, Indonesia

RM-04 Low-Temperature Thermomagnetic Method and Identification of

Impurities in Ni Hyperaccumulator Plants

RM-05 Testing the Effectivity of Magnetic Stirrer in Extraction of Magnetic

Minerals from Riverine Sediments

RM-06 Identification of Magmatic Processes using Magnetic Method and

Petronenesis Approaches in Ijen Volcanic Complex, Banyuwangi, Jawa

Timur

RM-07 Magnetic Characterization of Pyroclastic Density Current (PDC) of The

1257 AD Eruption of Mt. Samalas, Lombok, Indonesia: Preliminary

Results

RM-08 Distribution Pattern of Magnetic Minerals and Heavy Metals in sediments

from Lake Limboto, Gorontalo

RM-09 Characterization of Magnetic Minerals and Heavy Metals from Sediments

in Tributaries of Citarum River, West Java

RM-10 Magnetic Susceptibility and Element Composition of Mangrove Sediment

in Malang, East Java Indonesia

RM-11 Magnetic Susceptibility and Dielectric Properties of Peatland in Central

Kalimantan, Indonesia

RM-12 Magnetic Susceptibility, Fe Content and Morphology of magnetic mineral

extracted from surface sediment of Kamp Walker and Hubai River as an

Inlet of Sentani Lake, Papua-Indonesia

RM-13 Paleomagnetism and Geochronology of Granitic Rocks in Central

Sulawesi, Indonesia: Implications for Tectonic Setting

RM-14 The Characterization of Magnetic Soil in the Burnt Garbage Zone at

Garbage Disposal Jatinangor

RM-15 Comparation high calory between low calory of coal using Susceptibility,

Electric Conductivity(EC), pH (Potential of Hydrogen) parameter in

Mining field Bengkulu, West Sumatera, Indonesia.

RM-16 Analysis of Pollution in Agricultural Land Potential Using Rock

Magnetism Method

82

Pollution Detected Innovation of The Hazardous and

Toxic Substance Disposal by Magnetic Susceptibility

Method around Cikijing River, Rancaekek for testing

water quality standards

Yovan Prananda1, Febri Taufik

1, Alief Rizki

1, Fikrianti Surachman

2, M Hardian

T3, Naufal Rachman Akbar

4, and Widodo

1

1Geophysical Engineering, Bandung Institute of Technology, Ganesa St. Indonesia

2Pharmaceutical Care, Bandung Institute of Technology, Ganesa St. Indonesia

3Chemistry, Bandung Institute of Technology, Ganesa St. Indonesia 4Biology, Bandung Institute of Technology, Ganesa St. Indonesia

a)Corresponding author: [email protected]

[email protected]

Abstract. Water pollution can be a defect to surround the source of pollution. An example is Cikijing River, located

in Rancaekek, Bandung which has expected contaminated by water disposal. Total loss approach by Total Economic

Valuation is Rp 11.385.847.532.188 (± 11,4 trillion). One of the dangerous effect is the water quality in there. The

aim of this research is to know and prove water disposal contaminated in that river. This research was conducted by

mapping the magnetic anomaly which obtained from the surrounding river. Afterward, we was modelling the

research to get the susceptibility value. In the previous research, the geological condition of our research field is

Kosambi Formation (clay, sandstone, shale). The Kosambi Formation susceptibility value estimated 0.017 cgs unit

thereafter it used to be background susceptibility. As the result of modelling magnetic anomaly from the anomaly

map, we got the susceptibility contrast which has negative value. The relation between magnetic anomaly and

susceptibility indicated the hazardous and toxic substance pollution, which affected Cikijing River and around there.

Construction of an inexpensive field gradiometer based on

FGM3-sensor and SCL007 IC chip

Ganendra Chandra Ditya, Arno Germanndaputra Sulistyanto, and Satria

Bijaksana

Geophysical Engineering Program, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung

Jalan Ganesa 10, Bandung 40132, Indonesia


Abstract. Geomagnetic survey is a well known geophysical method that has used widely in exploration of natural

resources or minerals, archeology, and detection of underground pipe and metallic objects. Apart from using

magnetometers, geomagnetic survey might also uses gradiometers that use two instead of one magnetic sensor.

Magnetometers and gradiometers are rather expensive. In this research, a construction of inexpensive gradiometer is

reported. The instrument uses two fluxgate sensors, FGM-3 (Speake & Co. Ltd., UK) and electrical circuits that are

centered on SCL007 IC chip. The body of the instrument was constructed from non-magnetic PVC pipes. To

calibrate the instrument, two specific solenoids were built. Calibration processes produce chart that convert voltage

RM-01

RM-02

83

reading from the instrument to magnetic field gradient. The linear segment of the chart is considered as to be the

working range of the instrument. The instrument is now undergoing field test and good results are expected.

Magnetic Properties of Deposited Sediments in Surabaya

River, East Java, Indonesia

Mariyanto and Satria Bijaksana

Geophysical Engineering Program, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung


Abstract. Surabaya river is one of urban rivers in East Java Province, Indonesia that is a part of Brantas river that

flows in four urban and industrial cities of Mojokerto, Gresik, Sidoarjo, and Surabaya. The urban populations and

industries along the river pose serious threat to the river mainly for their anthropegenic pollutants. This study aims to

characterize the magnetic properties of deposited sediments in various locations along Surabaya river and correlate

these magnetic characters to the level of pollution along the river. Samples were taken and measured through a series

of magnetic measurements. The mass-specific magnetic susceptibility of deposited sediments range from 259.4 to

1134.8 × 10-8 m3kg-1. The magnetic minerals are predominantly pseudo-single domain magnetite with the grain size

range from 6 to 14 µm. Magnetic susceptibility tends to decrease downstream as accumulation of magnetic minerals

in sediments is affected not only by the amount of household and industrial wastes but also by sediment dredging,

construction of embankments, and extensive erosion from farmlands.

Low-Temperature Thermomagnetic Method and

Identification of Impurities in Ni Hyperaccumulator

Plants

Abd Mujahid Hamdan1, a)

, Satria Bijaksana1, Aiyen Tjoa

2, and Darharta Dahrin

1

1 Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung

2Master Program of Geothermal

Engineering, Institut Teknologi Bandung 2 Agriculture Faculty, Tadulako University


Abstract. Ni hyperaccumulators are plants that can absorb Nickel > 1000 ppm in dry biomass. Removal of

impurities in epidermis tissues of these plants is very important to good measurement and characterization results. In

this paper, the results of low-temperature thermomagnetic experiments in identifying and removal of such impurities

are reported. In addition, the low-temperature thermomagnetic method is expected to be able to assess and describe

qualitatively the center of coordination complexes in molecules, ligands and the structure of bio-molecules in

hyperaccumulators. Measurement results showed that the samples that have been cleaned with alcohol, methanol,

and detergent still demonstrate their ferromagnetic mineral impurities. The assumption is also confirmed by TEM

(transmission electron microscopy) investigation.

RM-03

RM-04

84

Testing the Effectivity of Magnetic Stirrer in Extraction of

Magnetic Minerals from Riverine Sediments

Gesti Cita Novala, Sudarningsih, Silvia Jannatul Fajar, Marianto, Kartika Hajar

Kirana, and Satria Bijaksana

Engineering Geophysics Program, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung


Abstract. Magnetic methods have been used widely in environmental studies as they are useful in inferring heavy

metal pollution in soil and sediment. In many studies, magnetic methods often require observation of magnetic

grains extracted from sediments. As the quantity of magnetic minerals in sediments is very low, such extraction

technique is often either unsuccessful or inconsistent. In this study, we reported the effectiveness of magnetic

extraction using magnetic stirrer and manual extraction method for riverine sediment. The effectiveness of such

method tested by measuring both not extracted sediment and extracted magnetic grains through a number of

magnetic measurements that include mass-specific magnetic susceptibility, isothermal remanent magnetization

(IRM) saturation, and anhysteretic remanent magnetization (ARM) decay. Results will be presented.

Identification of Magmatic Processes using Magnetic

Method and Petronenesis Approaches in Ijen Volcanic

Complex, Banyuwangi, Jawa Timur

Aditya Pratama1, Abd. Hafidz

1, Mirzam Abdurrachman

2, and Satria Bijaksana

1

1Engineering Geophysics Program, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung

2Geological Engineering Program, Faculty of Earth and Science Technology, Institut Teknologi Bandung


Abstract. Reliable volcanic map and deep understanding of magmatic processes are very important in exploration of

natural resources and mitigation of volcanic hazards. The conservative method in volcanic mapping still depends on

qualitative approach so that it often fail to characterize volcanic products properly. Rock magnetic methods are quantitative

approach that classify rocks based on their magnetic properties. In this study, magmatic processes in basaltic lavas from Ijen

volcanic complex in Banyuwangi, East Java were studied using combined rock magnetic and petrogenesis approaches.

Samples of basaltic lavas from 13 localities were measured for their mass-specific magnetic susceptibility. The samples were

also subjected to isothermal remanent magnetization (IRM) saturation, anhysteretic remanent magnetization (ARM) decay,

and magnetic hysteresis measurements. The samples were then also subjected to petrographic and X-ray Fluorescence

Spectrometry (XRF) analyses for their minerals composition and petrogenesis. Preliminary results show that the distinction

in magnetic characters might be due to differences in magma oxidation level during formation of magnetic minerals.

RM-05

RM-06

85

Magnetic Characterization of Pyroclastic Density Current

(PDC) of The 1257 AD Eruption of Mt. Samalas, Lombok,

Indonesia: Preliminary Results

Arif Wijayaa), Satria Bijaksana

b) and Silvia Jannatul Fajar

c)

Engineering Geophysics Program, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung,

Bandung 40132, Indonesia

a)



[email protected]

Abstract. The 1257 AD Mt. Samalas eruption (Lombok, Indonesia) is one of the major volcanic eruption that cause

global climate change and ejected thick layers (50 m) of pyroclastic density current (PDC). In this study, this PDC

deposits from two different locations, namely Luk and Jugil, in northern coast of Lombok were subjected to series of

magnetic measurements that include mass-specific magnetic susceptibility, isothermal remanent magnetization

(IRM) saturation, anhysteretic remanent magnetization (ARM) decay as well as hysteresis parameter. Prior to

magnetic measurements PDC samples were sieved through to divide the samples in five different grain sizes, i.e.,

clay, silt, fine sand, coarse sand and granule and magnetic measurements were carried out for each grain size. The

results show that the predominant magnetic mineral in all samples is PSD (pseudo-single domain) and MD (multi

domain) magnetite. However, the mass specific magnetic susceptibility of clay size samples from Luk (~ 501 × 108

m3/kg) differ significantly from that of Jugil (~ 848 × 108 m3/kg) suggesting although the deposits from Luk and

Jugil were of the same sources, they came from different eruption events. So far, the concentration dependent

magnetic parameter, i.e., mass-specific magnetic susceptibility is still the best parameter to identified PDC deposits

of Mt. Samalas based on their eruptive events.

Distribution Pattern of Magnetic Minerals and Heavy

Metals in sediments from Lake Limboto, Gorontalo

Raghel Yunginger1, a)

, Satria Bijaksana1, b)

, Darharta Dahrin1, c)

, and Siti

Zulaikah2, d)

1Engineering Geophysics Program, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung

2Physics Department, Faculty of Mathematics and Natural Sciences, Malang University

a)

Corresponding-author: [email protected] b)



[email protected]

Abstract. Recorded in rocks, sediments, and soils, magnetic properties could serve as proxy indicators for

environmental changes in the past. Among the lakes in the island of Sulawesi, Indonesia, Lake Limboto one that is

currently experiencing fast sedimentation process that shrink its area significantly to the extent that Indonesian

government classified this lake as a critical that need immediate rehabilitation. In this study, surface sediments from

17 points throughout Lake Limboto Gorontalo were subjected to series of magnetic measurements to characterize

their lithogenic and anthropogenic components. Prior to magnetic measurements, the sediments were sieved (in 325

mesh size) so that only fine particles were analyzed. The magnetic methods include measurements of mass-specific

magnetic susceptibility meter, IRM (isothermal remanent magnetization) saturation and ARM (anhysteretic

remanent magnetization) decay. These magnetic measurements were complemented by AAS (atomic absorption

spectrophotometer). The results of these measurements will be presented.

RM-07

RM-08





86

Characterization of Magnetic Minerals and Heavy Metals

from Sediments in Tributaries of Citarum River, West

Java

Rizky Ramdani, Sudarningsih, and Satria Bijaksana

Engineering Geophysics Program, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung


Abstract. Magnetic methods have been used widely in mapping and detecting pollution in riverine environments.

Compared to geochemical methods, magnetic methods are generally faster and more economical, One of the major

rivers that heavily polluted in West Java is Citarum that supply water to millions of people. In this study, magnetic

characterization and heavy metal analyses were subjected to sediments from six tributaries of Citarum in the

southern part of Bandung to identify the roles of each tributary in supplying magnetic minerals and heavy metals to

the main body of Citarum. Sediment traps were set in these tributaries during the month of July 2016 for three

weeks. In the laboratory, the sediments were sieved (with 325 mesh) and then air dried. Sediment samples were then

subjected to magnetic measurements that include measurements of mass-specific magnetic susceptibility meter, IRM

(isothermal remanent magnetization) saturation and ARM (anhysteretic remanent magnetization) decay. The samples

were also subjected to AAS (atomic absorption spectrophotometer) as well as SEM (scanning electron microscopy)

analyses. The results of these measurements will be presented.

Magnetic Susceptibility and Element Composition of

Mangrove Sediment in Malang, East Java Indonesia

Rosyida Azzahroa), Siti Zulaikah

b), Markus Diantoro

c), and Pranitha Septiana

Budid)

Departement of Physics, State University of Malang,

a)

corresponding author: [email protected] b)



[email protected]

Abstract. Mangrove sediments have a unique characteristics of depositional environment. Sources of sediment in

mangrove area come from allocthonous and from aothochtonous. In this case, we investigated the magnetic

properties and chemical element compotition of the surface sediments in Clungup mangrove conservation located in

southern of Malang East Java Indonesia. The sample were taken from eight site, four site were taken from the oulet

of the river, and the rest were taken from mangrove conservation which contacted to the ocean. The measurement of

magnetic susceptibility was conducted by Bartington Magnetic Susceptibility dual frequency and the chemical

composition of mangrove sediments conducted by X – Ray Flourensence apparatus. The magnetic susceptibility of

low frequency (χLf) were ranged between (0,051 – 10,578)×10-6m-3kg-1, which shows that magnetic susceptibility of

estuary sediment is higher than that of sediment from mangrove conservation. Based on XRF analysis, we identified

seven heavy metals (Fe, Mn, Zn, Cu, Ni, Cr, Hg) are dissolved in that mangrove sediment. Fe element is still high

concentration as in common sediment.

RM-09

RM-10


87

Magnetic Susceptibility and Dielectric Properties of

Peatland in Central Kalimantan, Indonesia

Pranitha Septiana Ba), Siti Zulaikah

b), Arif Hidayat

c), and Rosyda Azzahro

d)

Department of Physics, State University of Malang. Jl. Semarang 5, Malang

a)

Corrresponding author: [email protected] b)



[email protected]

Abstract. Peat soil is wealth spread in Indonesia which includes limnis sediment that has not been used optimally. In

this study, we identify the magnetic susceptibility and dielectricproperties of peat land in Central Kalimantan,

Indonesia at six locations to characterize magnetic minerals of the peat land by using the Bartington Susceptibility

Meter (MS2B) dual frequency and to determine the nature dielectric constant. The average of magnetic susceptibility

is known at locations T1, T3 and T5 has a value range of magnetic susceptibility 6,92.10-8 m3 / kg up to 9,22.10-8

m3 / kg may classified as paramagnetic mineral. While T2, T4 and T6 which range of magnetic susceptibility from -

0,573.10-8 m3 / kg to -0,151.10-8 m3 / kg, was classified as diamagnetic mineral. Magnetic minerals in six

locations peat deducted aspyrite (FeS2) and epidote (Ca, Fe, Al silicate) due to XRF analysis. Based on the magnetic

suseptibility frequency dependence and magnetic susceptibility of low frequency, magnetic minerals grain was

dominated by Single Domain - Pseudo Single Domain (SD-SSD) and some sample shows Superparamagnetic (SP)

and Multi domain (MD) grains. Meanwhile, the dielectric constant was maximum at T6.4 of around 35 and the

minimum value at T1.11 of around 21.The high magnitude of dielectric constant could indicate samples pore is

reduced.

Magnetic Susceptibility, Fe Content and Morphology of

magnetic mineral extracted from surface sediment of

Kamp Walker and Hubai River as an Inlet of Sentani

Lake, Papua-Indonesia

Siti Zulaikah1, Dian Sisinggih

2, Zem Dani

2, Mahfud David Ong

2, and Yusuf

Bungkang3

(1)Jurusan Fisika FMIPA Universitas Negeri Malang

Lab Sentral Universitas Negeri Malang (2)

Jurusan Teknik Pengairan Universitas Brawijaya (3)

Jurusan Fisika Universitas Cendrawasih


Abstract. As an inlet of Sentani lake, Kam Walker and Hubay river has a different environment characteristic, i.e.

Kamp Walker has a proximate inhabitant, while Hubay has relatively natural environment. In this study, we

conducted measurement of magnetic susceptibility, Fe content and morphology of magnetic mineral extracted from

surface sediment of that two rivers that would be benefit for deeply understanding of Sentani lake sediment

characteristic. The magnetic susceptibility of low frequency of the sample from that two rivers are varies from (lf)

11.105 10-6 kg/m3 to 24.958 10-6 kg/m3 for Kam Walker with dependence frequency susceptibility from fd

0.031% to 0.367% and (lf) 4.561 10-6 kg/m3 to 16.926 10-6 kg/m3 with fd 0.104% to 1.033% for Hubay. Fe

content of the sample from the two river also shows a different average i.e around 60% for Hubay and 50% for Kam

Walker. That different value may because of the source of magnetic mineral on the two sediment may are lithogenic

for the Hubay and lithogenic and antropogenic for Kam Walker. The morfhology of magnetic mineral, based on the

SEM image shows a rounded and crystalline magnetic mineral.

RM-11

RM-12



88

Paleomagnetism and Geochronology of Granitic Rocks in

Central Sulawesi, Indonesia: Implications for Tectonic

Setting

Muhammad Rusli M 1, 4

, Subagyo Pramumijoyo2, I Wayan Warmada

2, and

Wiwit Suryanto3

1)Doctoral Program, Geological Engineering, Universitas Gadjah Mada

2)Depth. Geogical Engineering, Universitas Gadjah Mada

3)Depth. Geophysics, Universitas Gadjah Mada

4Geophysics Study Program, Tadulako University


Abstract. Paleomagnetism and geochronology of granitic rocks from Central Sulawesi, especially from Palu area are

presented in order to elucidate their Characteristic Of Remanent Magnetization (ChRM) and implication for

tectonic setting. The granitic rocks in these are as are dominated by granite and Monzonit-Quartz in composition,

with high-K calc-alkaline photasik (KAP) and show metaluminous-peraluminous affinity. Paleomagnetic analyses of

37 specimens from 7 sites yield Characteristic Remanent Magnetization (ChRM) directions. The measurement

results display a means direction (D=23.4, I=-27,7°, α95=16.40°, k=14.50). Interpretation the results show the

relationship syncollision between Sulawesi Island with micro-continent plate Banggai-Sula and are syn-kinematic

with Faulting Palu-Koro were active at of Neogen until now.

The Characterization of Magnetic Soil in the Burnt

Garbage Zone at Garbage Disposal Jatinangor

Faris Sarma Putraa), Denis Candra, Fikri Zain Karim

b), and Eleonora Agustine

c)



a)



[email protected]

Abstract. Garbage is a material that has no longer being used after a certain process. A garbage at jatinangor region

isn’t well managed that will harm the environmental itself, accordingly to that so we made a research which aim to

recognize the soil characterization in physical way at burnt zone Jatinangor site. The physical parameter will be

observed about soil susceptibility itself. Susceptibility research of the soil contaminated that affect from another

factor will be bigger because the soil itself already contaminated by another material – material which already exist

by the process of the burnt soil. When susceptibility value of soil will increase, so the level of soil fertility will be

decrease. We will see the comparison how much the contaminated level from the data comparison coring has been

do in the 2 site, that is a burnt soil and the original soil that has zero contaminated factor.

RM-13

RM-14

89

Comparation high calory between low calory of coal using

Susceptibility, Electric Conductivity(EC), pH (Potential of

Hydrogen) parameter in Mining field Bengkulu, West

Sumatera, Indonesia.

Timothy Antonio, Muhammad Khodhi Robbani, and Eleonora Agustine

University of Padjadjaran (Unpad), Faculty of mathematical and science, Department Geophysics

Abstract. Calorific value of coal is important in the production of coal mines, Nowdays, to identify calorie of coal

requires process in a long time. There has been no research to identify calorie of coal using a rock magnetism

method based on parameters Susceptibility, Electrical Conductivity (EC) and pH (Potential of Hydrogen).

Advantages of calory analysis on coal using this method are efisiens in determining the outcome. One field in

Bengkulu, West Sumatra, Indonesia is a coal mining area with a variety of high and low calorific value as the

location of reviews of research. Identification study was conducted in calorie coal in Bengkulu, West Sumatra,

Indonesia for coal mining land has a variety of low and high calorific value as the location of reviews of research.

Coal with high calorie and low calorie in this study is taken by way of coring as deep as 60cm in two locations of

this research, the first point in a mining are a with a low calorific value and the second point in a mining area with a

high calorific value. By using rock magnetism method on these both object of coal that has a high calorific value and

low will get a comparison of the physical properties of value Conductivity, Susceptibility. From these physical

properties can be identified character of high and low calory of coal. Data processing are using Bartington MS-2B

and Hanna combo meter to see the value of Ph,EC. The results of the measurement of physical parameters for the

susceptibility of low calory coal is 48 and 0.18 dS / cm. pH low calory coal value is head to alkaline and high

calorie coal head to the acid. low calory coal has a susceptibility and EC values higher than high-calorie coal, high

susceptibility value indicates the distribution of magnetic minerals that are contained in the coal for more.

Analysis of Pollution in Agricultural Land Potential Using

Rock Magnetism Method

Adinda Syifa Azharia), Eleonora Agustine

b), and Dini Fitriani

c)



a)



[email protected]

Abstract. Industrial activities have the potential to make pollution in agricultural land, the waste contains poisonous

material and it is dangerous for the environment. In general, waste from factory is dumped directly into the river, but

in the current study an object that is going to be conscientious is soil on around mill. There are three sampling sites

are around fertilizer plants, feed mills and original uncontaminated soil. This research has been conducted to assess

the impact of pollution resulting from the two mills for the environment. Physical parameters that used is magnetic

susceptibility. Sampling was conducted using the method of magnetic susceptibility of rock to see the value of low

frequency (XLF) and Frequenccy Dependent (FD%) using Bartington MS2B. The results from this study is at a

location close to the fertilizer plant at a depth of 0-5 cm has a value susceptibility low frequency (XLF) = 187.1 -

494.8, FD (%) = 1.37 - 2:46, at a depth of 6-10 cm susceptibility value of low frequency (XLF) = 211 - 832.7, FD

(%) = 1.04 - 5.37. Results in the area of animal feed mill at a depth of 0-5 cm value susceptibility low frequency

(XLF) = 111.9 - 325.7, FD (%) = 0.8 - 3.57, at a depth of 6-10 cm cm value susceptibility low frequency (XLF) =

189.2 to 386.8, FD (%) = 0.33 - 3.07. Results in the original soil at a depth of 0-5 cm susceptibility value of low

frequency (XLF) = 1188.7 - 2237.8, FD (%) = 2.75 - 4.65, at a depth of 6-10 cm value susceptibility low frequency

(XLF) = 977.7 - 2134.7, FD (%) = 3.06 - 6.21.

RM-15

RM-16




Contents - Geo-EM 2017gem2017.org/Program Book.pdf · 2 Contents Preface from the Chairman of the...

Documents

Transcript of Contents - Geo-EM 2017gem2017.org/Program Book.pdf · 2 Contents Preface from the Chairman of the...