IUGF Presentation FINAL
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Transcript of IUGF Presentation FINAL
Potential Shale Gas Basins of India
Possibilities & Evaluations
Dr.V.K.Rao
Conventional Oil/Gas Exploration
In pursuit of conventional Oil/Gas Exploration
over the years,Geologists regarded Shales as:
Cap rock by virtue of their impermeable nature
and compactness thus acting as good seal
Source Rock by virtue of the richness of
organic material content, its maturity ,generation
potential and geographic spread over large
areas
Gauging Shale Gas reservoirs
Methane in shales is generated from the transformation of organic material by bacterial(biogenic) and geo-chemical (thermogenic) processes
The gas so generated gets stored by multiple mechanisms as free gas in micropores/microfractures and as adsorbed gas on the internal surfaces
Thus shale gas is a combination of sorbed gas and micropore gas
The challenge in these accumulations is not of finding it BUT to exploit it commercially
Thus it is more of technological challenge which has been met by innovative hydraulic fracturing and multi-lateral horizontal drillingtechniques.
USA has emerged as the pioneer in developing and using this technology for commercial production of shale gas.
Geological parameters for Shale gas
evaluation
Thickness & areal extent
Organic matter type & its richness
Thermal maturity
Mineralogy,Faults & Fractures
Gas content /Gas Storage
Adjacent water bearing Formations
India-Likely acolyte of shale Gas revolution
Rapidly growing Gas markets
India has high Natural Gas prices
Increasing dependancy on LNG imports
Nascent CBM industry
Widening Demand-Supply gap
Rising Energy Consumption
Rising economic growth
Potential Shale Gas Basins
• : Potential
• Cambay
• Assam-Arakan
• Gondwana
• Vindhyan
• Rajasthan
• Bengal
• Krishna-Godavari
• Cauvery84
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C
B
Cambay Basin
Narrow elongated rift
Basin extensively
explored petroliferous
basin
Sanchor-Patan Block
Ahmedabad-Mehsana
Block
Tarapur-Cambay Block
Broach-Jambusar Block
Narmada-Tapti Block
Shales in Stratigraphy
• Tarapur Fm(Up.Eocene-
Oligocene)
• Kalol Fm(Mid.Eocene)
• Younger Cambay Shale
Fm(Lr.Eocene)
• Older cambay Shale
Fm.(Paleocene-
Lr.Eocene)
• Olpad Fm.(Paleocene)
Cambay Shale Fm.
Source:DGH
Formation Thickness(m) TOC (%) VRo (%) Kerogen Type
Olpad 340-2700 1.5-4.0 0.75 II & III
Older Cambay
Shale
500-1900 1.5-4.0 0.75-0.85 II & III
Younger
Cambay Shale
520-1500 1.00-4.0 0.75-0.85 II & III
Kalol 200-300 0.75 II & III
Tarapur 60-400 0.53
Shale characteristics of Cambay Basin
Prognosticated Resource Potential of 90 TCF is estimated
Assam-Arakan Basin
• Assam Shelf
• Naga-Schuppen Belt
• Assam-Arakan Fold
belt
• Zunki Schuppen Belt
• Ophiolite Complex
• Naga Metamorphic
Complex
Shales in Stratigraphy
Formation Thickness(m)
TOC
%
VRo % Kerogen
Type
Up.DisangGp.
2000-3000 0.69-4.0 0.90-1.94 II & III
Kopili >500 1.0-6.2 0.92-1.44 II & III
Jenam 900-1200 2.5-4.5 0.64-1.20 II & III
Bhuban 800-1000 No data 0.90-1.00
No dataBokabil 400-1000
Shale characteristics of Assam-Arakan Basin
Prognosticated Resource Potential of 55 TCF is estimated
Gondwana Basins
(South Rewa Basin)
• Intracratonic rift Graben Basin
• Criss crossed by a number of ENE-WSW trending Faults
• Lr. & Up. Gondwana sediments are present .
• Barakar and Raniganj Fms. Consist of coal seams and massive shales /sandstones
• Deccan Trap outpouring during Late Cretaceous -Paleocene
Age GROUP Formation Thick-ness (m) Generalised lithology
Recent UP.
GONDWA
NA
Alluvium
Cretaceous to Paleocene Deccan Traps Basalt and Dolerite
Unconformity
Late Cretaceous Lameta 50 Sandstone cake, clays Limestone,
Mart.
Unconformity
Early Cretaceous Bansa Chandia 100 Sandstone, Conglomerates, clays,
shales and Chert
Unconformity
Late Traissic Parsora 450 Sandstone, Mudstone
Middle-Early Triassic LR.
GONDWA
NA
Pali-Tihki 450-600 Mudstone, shale & sandstone
Unconformity
Raniganj 800-1250 Sandstone, Shale, Clays, Coal
Barren Measures 140-600 Sandstone, Red clays
Early Permian Barakar 175-900 Sandstone, grey shales and coal
Umaria Marine Bed 3-5 Fossiliferous sandstone and clays
Unconformity
Talchir 15-400 Sandstone & Shale,
Manendragarh Marine Bed Green Shale & Sandstone
Unconformity
Precambrian Basement Granite, Gneiss, Schist, Phyllites
Shales in Stratigraphy of South Rewa Basin
Geological section along NW-SE trend of South Rewa Basin
Formation Thickness(m) TOC
%
VRo % Kerogen
Type
Raniganj 800-1250 1.06-
18.40
0.40-0.60 III
Barakar 170-900 1.06-
14.72
0.40-0.60 III
Shale characteristics of South Rewa Basin
CHANDRAPUR
ASWARAOPETA
BHADRACHALAM
ASIFABAD
ASP-1
0 30 KM
Scale
SIRONCHA
BHUTARY
+ + +
+++
+
++ +
+
+
+
+
+
+++
++
+
+
+
+++
+
+
+
++
+ + +
+
++
+ + ++ + +
++
+ + + ++ + + +
++
+
+
+ + ++
++ +
+ ++ +
+
+
++ +
++ + + + + +
++
+ + ++ +
+
+
+ + +
++
+ ++
+
+
++ +
+
+
++
+
++
+ +++
CHINTALAPUDI
NORTHWESTERN SECTOR
CENTRAL SECTOR
SOUTHEASTERN SECTOR
NORMAL / REVERSE FAULT
WRENCH FAULT
+
ANTICLINAL AXIS
SYNCLINAL AXIS
BASEMENT
PG-ONN-2001/1
Gondwana Basins
(Pranhita-Godavari Basin)
Intracratonic Rift Basin trending WNW-ESE
Three Sub Basins are identified:
-Eastern Albaka
-Central Pakhal
-Western Chandarpur
BASEMENT+
SANDSTONE SHALE /
CLAYSTONE
COAL
AGESUPER
GROUPFORMATION
LIT
HO
LO
GY
PALEOCENE -
CRET.
JURASSIC
TRIASSIC
LO
WE
R
GO
ND
WA
NA
PERMIANBELLAMPALLI
BASEMENTPRECAMBRIAN
TALCHIR
BARAKAR
JAI PURAM
POTAMADOGU
MANER
MALERI
TARVAI
KOTA
DECCAN TRAP / LAMETA
THICK.
(m)
CHIKIALA / GANGAPUR
KUDUREPALLI
KHANAPUR
V V VV V
+ + +
1
1.
UP
PE
R
GO
ND
WA
NA 400
600
900
1200
150
600
200250
350
600
300
400+
Stratigraphy in Pranhita-Godavari Basin
Formation/
Group
Thickness
(m)
TOC
%
VRo % Kerogen
Type
Lower
Gondwana
Gp.
400-550 6.41% 0.67 III
Upper
Gondwana
Gp.
900-1100 No Data
Shale characteristics of Pranhita-Godavari Basin
Vindhyan Basin
• Peri-Cratonic basin
located in the central
part of Indian massif
Main Tectonic
Features are:
• Great Boundary Fault
• Bundelkhand massif
• Son-Narmada Geo-
fracture Zone
Shales in Stratigraphy
• Binita,Nimbahera
&Suket shales
• Rewa, Ganorgarh and
Sirbu shales
• Chakaria Olive,
Hinolta and Pulkova
shales
WEST VINDHYAN EAST VINDHYAN
GROUP SUB
GROUP
FORMATION THICKNESS(M) FORMATION THICKNESS(M)
UPPER
VINDHYAN
BHANDAR SIRBU SHALES 250 SIRBU
SHALES
85
SAMARIA 30 -
GANURGARH 75 GANURGARH 45
REWA UPPER REWA 150 UPPER REWA 55
BIJAIGARH 35
LOWER
VINDHYAN
SEMRI SUKET 30 CHAKARIA 320
NIMBHERA 150 PULKOVA 210
BINOTA 100
HINOTA 120
Shales in Vindhyan stratigarphy
Formation Thickness(m) TOC
%
VRo % Kerogen
Type
ChakariaOlive shale
185 0.60-1.04
No Data
II & III
Hinota shale 90 0.56-3.89 II & III
Rewa shale 225 0.07-0.40 II&III
Pulkova shale 210 35.0-37.85 II & III
Suket shale 100 0.04-0.37 No Data II & III
GanurgarhShale
75 No Data
Shale characteristics of Vindhyan Basin
Cauvery Basin
• Intracratonic rift basin located between two cratonic masses viz: Indian peninsula and Sri Lankan Massif
Main Tectonic elements are:
• Ariyalur-Pondicherry sub basin
• Kumbhkonam-Madnam-Portonovo High
• Tanjore-Tranquebar sub basin
• Pattukottai-Mannargudi-Karaikal High
• Nagapattinam sub basin
• Vedarniyam High
• Pattukuttai-Manargudi high
• Ramnad-Palk Bay sub basin
• Mandapam Ridge
• Gulf of Mannar sub basin
• Vedarniyam – Tiruchirapally terrace
Shales in Stratigraphy
• Sattapadi Shales in
Uttatur Group
• Kudavasal shales &
Portnovo Shales in
Ariyalur Group
• Komarakshi Shales in
Ariyalur Group
• Karaikal Shales in
Nagore Group
Geological Section across Cauvery basin
Isopach and Shale disposition
Sub Basin Thickness(m)
Approx;
TOC
%
VRo % Kerogen
Type
Ariyalur-Pondicherry
1500 0.31-2.78 1.15 II & III
Tranquebar 2000 0.31-4.76 0.65-0.79 II & III
Nagapattinam 1500 1.68-1.89 0.45-0.34 II & III
Mannar 2000 1.50-1.75 1.0-1.12 II & III
Shale characteristics of Cauvery Basin
Other Prospective Basins
• Krishna-Godavari
Basin
• Bengal Basin
• Rajasthan Basin
Summary
• Shale gas Exploration in India is in nascent stages
• An anology with USA shale Gas basins implies that India could have significant shale gas potential in its major sedimentary basins
• Shale Gas production could be a “Game changer”in energy mix
• In order to assess the shale gas resources basic shale gas specific data requires to be generated through laboratory studies and well data in major shale gas prone basins
Summary
• ONGC has already initiated the process and 1st
Shale gas exploratory well is under drilling in
Bengal basin.
• Initiatives being taken by Govt. of India through
DGH & MoPNG to have international multi task
ventures is a welcome step in this direction
• We are awaiting for the 1st bid round of shale
gas blocks proposed to be offered by MoPNG
by the end of 2011.