3D Reservoir

Characterisation

Geophysical Analysis

Lithology &

Saturation, porosity

Structural/ Strat.

Model

3D Seismic

Interpretation

Reservoir

UTP COURSE : ReservoirGeophysics

AttributesAttributes

Field Economics

Up or Down

Scale ??

Final Reservoir

Sedimentology

Model Characterisation

Model/Static

Fluid Flow Modelling

• Well Test

•Permeability

•PVT/MDT

•Production History

Matching and

Forecast

Facies

Hi Res-Sequence

Stratigraphy &

Environment

Sequence boundary

Maximum Flooding

SurfacePetrophysical/

Wire Line

Property

Model

Reservoir

Simulation

Dynamic

Optimum

Field

Development

Plan

GeostatisticsVariogram

Uncertainity

Final Reservoir

Model

Model

PlanningBlock

Acquisition

Frontier

Exploration

Prospect

EvaluationDrilling

Discovery Volumes AppraisalReserve &

Economic

LIFE OF FIELD

ExplorationExploration

AppraisalAppraisal

Reservoir

Static ModelSimulation

Production

Forecast

PVT

RFT

DST

Development

Plan

Infill

Drilling

Field DevelopmentField Development

EOREORFLOODI2G FLOODI2G

I2JECTIO2I2JECTIO2 SECO2DARY SECO2DARY

RECOVERYRECOVERY

PRODUCER & PRODUCER &

I2JECTORI2JECTOR

Secondary RecoverySecondary Recovery

“Exploration Success Through

Innovative Solution

ACQ/PROCESSI2G - Seismic Data Acquisition- Seismic Data Processing

- Survey and Positioning- Seismic Survey Design

- OBC 4 C / Shear Seismic

GEOPHYSICAL EXPERTISE

SEISMIC

I2TERPRETATIO2

”

SEISMIC METHOD

QUA2TITATIVE

GEOPHYSICS- AVO & Rock Physics- Seismic Inversion

- Structural Modeling & Imaging

Seismic Attribute Analysis

-Reservoir Modelling

-Full Field Development

- Time Lapse Seismic

I2TERPRETATIO2

3D Visualisation

Seismic Interpretation

RESERVOIR

GEOPHYSICS

SEISMIC SECTIO2 FROM 2ORTH VIET2AM

55TOP CARBO�ATE RESPO�SE IDE�TIFIED FROM

GEOLOGICAL FIELD A�ALOG ( �ORTH VIET�AM )

BrazilWest Nile Delta

DEEPWATER IMAGES

66

Courtesy BG plc

L in e 3

5 0 0 m

West Africa

Courtesy BP

Courtesy Enterprise Oil/Shell

GORGE

DEEPWATER GEOLOGICAL MODEL

& SEISMIC RESPO2SE

3D SEISMIC IMAGE

SHALE DIAPIAR

POCKMARK

SEDIME2T

TRA2SPORT

FA2 LOBE

In Deep Water environment hi – res 3D images provide excellent

tool to develop, Calibrate & Test Geological conceptual models.

Sand-rich environment

Petroleum System Processes

Seal RockSeal Rock

ReservoirRockReservoirRock

OilOil

WaterWater

Gas CapGas Cap

EntrapmentEntrapment

24803

120° F120° F

350° F350° FGenerationGeneration

MigrationMigration

RockRock

Source: AAPGSource: AAPG

FORWARD & INVERSE SEISMIC FORWARD & INVERSE SEISMIC PROBLEMPROBLEM

ACQUISITION

SYSTEMS

START

WAVELET

RECOVER

� Structure

� Velocity

� Rock, Fluid, Lithology

END

MO

DELLIN

G

INVER

SIO

N

t

99

EARTH PROPOGATION

EFFECT

CONVOLVE

EARTH MODEL

• Vp, Vs, ρ

• Porosity

• Structure

• Saturation

SEISMIC RESPONSE

DECONVOLVE

RECOVER

GEOLOGY

MO

DELLIN

G

INVER

SIO

N

t

**

THE SEISMIC EXPERIMENTInteraction of Geology & Geophysics

SEISMIC SOURCEGEOLOGICAL

STRUCTURE Depth

Km

Courtesy GX Technology

Various wave modesVarious wave modes

Up-going Wave

1111

Down-going Wave

Identify various wave types:

a) Downgoing wave c) distortion in wave shape

Snell’s Laws of Reflection and

common depth point (CDP)

method

Snell’s Laws of Reflection and

Refraction

Sin i/V1 = Sin r / V2

UnderstandingUnderstanding Wave BehaviorWave Behavior

1313

FAULTED SYNCLINAL STRUCTUREM

OD

ELLIN

G

Depth 2.0

km

3.0

INVER

SIO

N (IM

AG

ING

)

**

1414

SEISMIC DIFFRACTION RESPONSE

MO

DELLIN

G

Time 1.0

secs

2.0

INVER

SIO

N (IM

AG

ING

)

**

3D VISUALISATION OF 3D VISUALISATION OF

GAS FIELDGAS FIELD

Fault

Gas

1515

HorizonWell

Path

CONVOLUTION MODEL OF SEISMIC TRACECONVOLUTION MODEL OF SEISMIC TRACE

→→→→ →→→→ →→→→*

AI(t) RC(t) W(t) S(t

)

M O D E L I 2 G

→→→→ →→→→ →→→→*

I 2 V E R S I O 2

AI : Acoustic impedance RC : Reflection coefficient

W : Wavelet S : Seismic trace

2 2 1 1

2 2 1 1

V VRc

V V

ρ ρ

ρ ρ

−=

+

VELOCITY MODELLI2G

Figure 3.8.31 : Instantaneous Phase Map for E1213 reservoir. Comparison between 1984 and 2002 seismic data

Block S3 Block S3

Base survey (1984) Monitor survey (2002)

SEISMIC IN LIFE OF FIELDSEISMIC IN LIFE OF FIELD

By

DR DEVA GHOSH

Compiled by:

Salbiah Mad Sahad

SEISMIC INTERPRETATIONAL SEISMIC INTERPRETATIONAL

FRAMEWORKFRAMEWORK

By

DR DEVA GHOSH

P.R.S.B

Compiled by Salbiah Bt M

Sahad

Structure & Strat.

Mapping

Geological Models

Concept

3D Seismic

SEISMIC I2TERPRETATIO2 VALUE CHAI2

Recommendation

To Drill

Attribute Analysis

3D Seismic

Well Data

Rock Physics

Prospect

Evaluation

Resources

& Risks

3D VISUALISATION OF GAS FIELD3D VISUALISATION OF GAS FIELD

Fault

Gas

HorizonWell

Path

Depth map

GWC 1417m

Channels viewed using

transparency.

3D Visualisation of Channel Play

M A L A Y B A S IN

Channels maybe

difficult to recognize

on traditional

displays.

SEISMIC WAVE

0- +

High Frequency

10 – 60 Hz (Cycles/sec)

Polarity (Hard)(Soft)

Amplitude (-)

(Reservoir)

2525

0° Phase

90° Phase

180° Phase

Wavelength

λλλλ = v / ƒƒƒƒ

= 3000/30

Resolution = 25 m

= 100 m

Low Frequency

6 – 35 Hz

SEISMIC VARIABLES & ITS ATTRIBUTES

AMPLITUDE � Sand quality NTG

� Porosity

� Fluid & Lithology

2626

FREQUENCY

PHASE� Resolution

� Thin beds/Tuning

� Channel detection � Seismic well match

� Discontinuity faults

� Unconformity

All seismic attributes are linear combination of these three basic variable. While

interpreting seismic data use has to be made of all information derived from these attributes

Class I :

Structural Attributes

Classification of Seismic AttributesClassification of Seismic Attributes

Class 2 :

Spectral Attributes

Flat spot

DHI Indicator : Flat Spot

Class 3 :

Lithology/Porefill

Attributes

Structure and fault volume Interpretation can be

done with transparency in 3D Viz

Semangkok Timur-1

Semangkok Timur-2

Semangkok Timur Deep-1

Ridan-2

EC

EC

Semangkok Timur-1

Semangkok Timur-2

Semangkok Timur Deep-1

Ridan-2

EC

EC

Semangkok Timur-1

Semangkok Timur-2

Semangkok Timur Deep-1

Ridan-2

EC

EC

Semangkok Timur-1

Semangkok Timur-2

Semangkok Timur Deep-1

Ridan-2

EC

EC

Semangkok Timur-1

Semangkok Timur-2

Semangkok Timur Deep-1

Ridan-2

EC

EC

Semangkok Timur-1

Semangkok Timur-2

Semangkok Timur Deep-1

Ridan-2

EC

EC

Stratigraphic channels Imaging on

Spectral Decomposition Abrupt termination on AVO envelope

attribute in a gas reservoir, Sarawak

Amplitude shut off and Phase change on a

producing field in Malay basin

Better imaging at higher frequency

At 45 Hz At 65 Hz

I-25 Channel System

RMS Amplitude Extraction

Diwangsa-1

I-25 Channel System

STRATIGRAPHIC CHA22ELI2GMALAY BASI2

Korbu-1

Analog

Best Chances of Finding

sands are in Point bars3D Seismic Far Offset

Malay Basin Malay Basin StratigraphicStratigraphic Channel PlayChannel Play

Low sinuosity meandering channel

Seismic Image has to be

interpreted in context of

Depositional Environment .

Determine :

Geometry ( L/W/D) Sinuosity

Flow direction

3D Seismic Image Geological Models & Analogues

3D Visualization & Channel (white)

cutting coal layer

ATTRIBUTE ANALYSIS

Seismic Waveform Seismic Waveform FaciesFacies IdentificationIdentification

Seismic Waveform classification using supervised

neural network of geological facies well motif

INTERPRETIVE GEOPHYSICS

SEISMIC IMAGE

CRISP FAULT

IMAGING

3131

COHERENCY

Significance of AmplitudeSignificance of Amplitude

�� Quality of sand: NetQuality of sand: Net--toto--Gross.Gross.

�� Porosity.Porosity.

�� Pore fill: gas, oil or brine.Pore fill: gas, oil or brine.

�� LithologyLithology, hard on soft shale, coal., hard on soft shale, coal.

�� Thin bed Interference AVOThin bed Interference AVO

0.01

0.10

1.00

10.00

100.00

1000.00Perm

eability (m

d) Series1

Fluvial channelsFluvial channels

Proximal lower

shoreface

Distal lower

shorefaceFlood

plain

RESERVOIR QUALITY FROM SEISMICAMPLITUDE & FACIESRESERVOIR QUALITY FROM SEISMICAMPLITUDE & FACIES

POOR……… POROSITY GOOD

…… Seismic

Amplitude

Sedimentology & FaciesRESERVOIR

EFFICIE2CY

0.01

0.00 5.00 10.00 15.00 20.00 25.00

Porosity (%)

Reservoie Efficiency of K Reservoir In a Malaysia Field as aFunction Of Depositional Facies

Poor ………SAND QUALITY…… .’’ Good

POOR……… POROSITY GOOD

Bunga Zetung 1

Bunga Zetung 1

For Data From 20 to 30 Hz

Direct Hydrocarbon Indicators (DHI)Direct Hydrocarbon Indicators (DHI)

2ot all bright spots are DHI.For example: the

following can cause a bright spot

• Hard shale on soft shale.• Hard shale on soft shale.

• Brine sand.

• Anisotropy.

DHIs are best studied in the AVO-Inversion domain.

However, on the stacked section the DHIs have

recognizable patterns that an experienced

interpreter can detect.

• Structural conformity

GAS

3. ) INSTANTANEOUS 3. ) INSTANTANEOUS

FREQUENCY : DROP ( Gas FREQUENCY : DROP ( Gas

Play)Play)

Amplitude InterpretationAmplitude Interpretation: :

Direct hydrocarbon IndicatorsDirect hydrocarbon Indicators

Gas masking at crest

Gas-water contact

1.) STRUCTURE CONFORMABLE 1.) STRUCTURE CONFORMABLE

AMPLITUDE AMPLITUDE

Red – Low

Frequency

35352.) FLAT SPOT OF FLUID 2.) FLAT SPOT OF FLUID

CONTACTCONTACT

2D 3D

4.) AMPLITUDE SHUT OFF 4.) AMPLITUDE SHUT OFF

& PHASE REVERSAL& PHASE REVERSAL

Gas-water contact

KUMANG-1KUMANG-2

W

ES

T

AR

EA

EA

ST

AR

EAMo

del

KUMANG-3_Prop

I II

IIIGWC –1018 m TVDSS

STRUCTURE CO2FORMABLE AMPLITUDES – A DHI

BU-1 B80

BU-3 B80

BU-4 B80

BUD-1 B80

BU-3 B100

BU-3 D10

920

930

940

950

960

970

980

990

1000

BU-1 B80

BU-3 B80

BU-4 B80

BUD-1 B80

BU-3 B100

BU-3 D10

920

930

940

950

960

970

980

990

1000

In all closures related to Structure ( 4 way Dip or Fault )

Amplitudes conform to structure if related to Hydrocarbon

BU-3 D10

BU-4 D10

BU-2 D34

BU-3 D34

BU-4 D34

BUD-1 D34

BU-4 D36

BU-1 D60

BU-2 D60

BU-4 D60

Normal Water Line

Normal Water Line

0.433 psi/ft

Gas Line

0.08 psi/ft

1660 1680 1700 1720 1740 1760 1780 1800 1820 1840 1860 1880 1900 1920 1940 1960 1980 2000 2020 2040

Formation Pressure (psia)

1000

1010

1020

1030

1040

1050

1060

1070

1080

1090

1100

1110

1120

1130

1140

1150

1160

1170

1180

1190

1200

1210

1220

1230

1240

1250

1260

1270

1280

1290

1300

1310

1320

1330

1340

1350

1360

1370

1380

1390

1400

1410

Depth (m TVDss)

BU-3 D10

BU-4 D10

BU-2 D34

BU-3 D34

BU-4 D34

BUD-1 D34

BU-4 D36

BU-1 D60

BU-2 D60

BU-4 D60

Normal Water Line

Normal Water Line

0.433 psi/ft

Gas Line

0.08 psi/ft

1660 1680 1700 1720 1740 1760 1780 1800 1820 1840 1860 1880 1900 1920 1940 1960 1980 2000 2020 2040

Formation Pressure (psia)

1000

1010

1020

1030

1040

1050

1060

1070

1080

1090

1100

1110

1120

1130

1140

1150

1160

1170

1180

1190

1200

1210

1220

1230

1240

1250

1260

1270

1280

1290

1300

1310

1320

1330

1340

1350

1360

1370

1380

1390

1400

1410

Depth (m TVDss)

Gas Water Contact

PRESSURE PLOT

2ear Angle Far Angle

AVO Process

AVO CLASSES

23

AVO RESPO2SE I2 TURBIDITE

2EAR FAR

Both the primary target and a potential prospect show typical Class II type anomaly,

predrill. The primary target was discovery

SEISMIC SECTIO2

EXPLORATIO2 PITFALLAbandoned Clay Channel

FULL STACK AMPLITUDE

Channels

GSM 2008

Stack amplitude cannot

distinguish H.C sand from

clay channel

Importance of Low

Seismic InversionSeismic Inversion

SEISMIC INVERSION

Well AIInverted AI

(10-80 Hz)

Wavelet SeismicAI from Inversion

TRVEAcousticImpedance

Importance of Low Frequency

Inverted AI

(0-80 Hz)

FIG. 2 : (0 - 10Hz) LOW FREQUENCIES OF PRIME IMPORTANCE IN RECOVERING PROPER IMPEDANCE

3D SEISMICGEOLOGY

GEO-STATISTICS

WELL/PETROPHYSICAL

I2VERSIO2OUTPUT

Importance of Low

Frequency 0- 8HzSABAH, KINARUT

LITHOLOGY SECTION

Full Refl

Knr 2S2 Knr 2Knr 1

Shale

SandTD=8300ftah

Base Kinarut sand

Top

Lower

Kamunsu

sand

Knr 3

GWC

Vp / Vs

2.0

1.5

Shl

Snd

SIMULTANEOUS

INVERSION

3D SEISMIC

SAND

SHALE

FIG. 2 : (0 - 10Hz) LOW FREQUENCIES OF PRIME IMPORTANCE IN RECOVERING PROPER IMPEDANCE

3D REPRESE2TATIO2 OF AVO ATTRIBUTE

Vs

POISSON’S

RATIO

SHEAR

IMPEDANCE

B – THI2 BED

RESOLUTIO2

ACOUSTIC

IMPEDANCEVp

θθθθ

RATIO

ELASTIC IMPEDANCE

I2VERSIO2 IMPROVED

SEISMIC RESOLUTIO2

Courtesy CSMP

Coal

Channel

AI EI

CoalCoal--HC Discrimination in Elastic DomainHC Discrimination in Elastic Domain

Gas sand

CoalAI

AI

Coal HC Sand

EI

Q.I. Analysis

DHI

In EI domain coal effect can

Coal Masks HC & Channel

Response

In EI domain coal effect can

Overlap zone

Poisson’s Ratio

EI

Courtesy PETRONAS - PTT

Coal

EI

Seismic Amplitude InversionWORKFLOW

• 3D Seismic

(2ear, Mid, far)

• Well Data

• Rock Physics

• Geological Analysis

ACOUSTIC

IMPEDA2CE

Vs

Vp θθθθ

POISSO2’S

RATIO

SHEAR

IMPEDA2CE

ELASTIC

IMPEDA2CE

Seismic PropertiesVp , Vs ,Sigma, Rho

REFLECTIVIT

Y A.I./ E.I.

Pressure/

Saturation

Porosity

Sand%

Probalistic HC Prediction & Volume

Reservoir /Fluid

Properties

Porosity, Sand %,