SOURCE ROCK EVALUATION

Faculty: Dr. P.N. Kapoor

GT Lecture 18.08.2008

Source RockThe sediments that have been able to generate or may have the potential to generate hydrocarbons

Petroleum SystemAn integrated geological syst em that:-- Generates hydrocarbons (gas & oil)

-- Concentrates and traps them

-- Produces economic deposits

Four Main Steps-- Source: Rich in Organic Matter

-- Maturation & Generation: Burial Heating

-- Migration: Movement thru permeable beds

-- Trap (Reservoir & Seal): Structural & Stratigraphic

Cross Section of a Petroleum System(Foreland Basin Example)

Overburden RockSeal Rock

Reservoir Rock

Source Rock

Underburden Rock

Basement RockTop Oil WindowTop Gas Window

Geographic Extent of Petroleum System

Petroleum Reservoir (O)

Fold-and-Thrust Belt(arrows indicate relative fault motion)

EssentialElements

ofPetroleum

System

(modified from Magoon and Dow, 1994)

O O

Sedi

men

tary

Bas

in F

ill

OStratigraphic

Extent ofPetroleum

System

Pod of ActiveSource Rock

Extent of Prospect/FieldExtent of Play

Source Rock:Organic Matter

-- Maturation-- Generation of HC-- Migration

Possible facies distribution extending from inner shelf to bathyal environmentsIn sequence stratigraphic concept

Organic Matter Source

BITUMEN

Soluble organic matter in any Organic Solvent

KEROGEN

Insoluble organic matter in any Organic Solvent

ExternalElemental Analysis Palynofacies

PETROLEUMPRODUCTS

Vitrinite

InertiniteKEROGENType IV

KEROGENType III

(Hydrogen Poor)

KEROGENTypes I/II

(Hydrogen Rich)

INERTCARBON

BP(GCB)

RE

AC

TIV

E K

ER

OG

EN

INERT KEROGEN

REFRACTORYKEROGEN

From Visual estimation

Coal Petrology

From Geochemical techniques

GASC1-C5

compounds

OILC6->C6

compunds

Algal AmorphousPalynomorphs

Epidermal TissueResin S

AP

RO

PE

LIC

Brown Wood

Black Wood

HU

MIC

LiptiniteAlginiteExiniteCutinite

SporiniteResinite

LABILE KEROGEN

Kerogen Classification

Source Component Structure

Organic Matter components

Sediment Profile

Evolution of Organic Matter

ØDIAGENESISØCATAGENESISØMETAGENESIS

DIAGENESIS

Microbial and Chemical transformations of Organic Matter produce Biogenic Methane

CATAGENESISRepresents Time -Temperature controlled conversion of Microbially transformed products into Liquid and Gaseous Hydrocarbons

METAGENESIS

Production of stable Gaseous Hydrocarbons, Immobile Polyaromatic structures and Thermogenic Gas

Hydrocarbon Generation

Amount and type of hydrocarbons generated depend largely on type of Kerogen, catagenetic stage of Evolution for a given Volume of Source Rock

Hydrocarbon Kitchen

Zone in which a Source Rock is Mature to Generate Hydrocarbons

Kerogen Qualityv Assessed on Major Atomic

Constituents-C,H,O for their HC generation Capabilityv Crossplot of H/C vs O/C

depicts degree of evolution of Kerogen with increasing maturation

Kerogen Types

ØTYPE IØTYPE IIØTYPE III

TYPE I

ü Highest H & Lipid contentü High potential for HCü Derived from Algal/ Microbial

Lipids

TYPE II

ü Hig H & Lipid contentü High potential for HCü Derived from Phyto & Zoo

Planktons Lipids

TYPE III

ü Less H & more Oxygenü Low potential for HC

adequate for Gasü Derived from Terrestrial

Higher Plants

Types of Kerogen• Type I : algal kerogen

– “best” oil source– Lipid-rich

• Type II: herbaceous kerogen– Good oil source– Includes zooplankton (sapropelic)

• Type III: woody kerogen (coaly)– Good gas source– Rich in humic components

• Type IV: amorphous kerogen

Rock Eval Pyrolysis4 Parameters

ü S1ü S2ü S3ü Tmax

S1

Measures HC liberated by heating at Moderate Temperature

S2

Measures Petroleum Constituents generated by heating Kerogen at Higher Temperature

S3

Measures CO2 liberated by heating Kerogen at convenient Temperature to avoid dissociation

Tmax

Temperature recorded at max. of peak S2Used to measure Maturation Stage

S2/S3

Signifies type of HC to be generated from the Kerogen

Tmax

ØImmature Biogenic Gas < 435 0 C TmaxØMature Oil Generation > 435 0 C - < 450 0 C TmaxØMature Gas Generation > 450 0 C - < 470 0 C TmaxØPost Mature Thermal Gas > 470 0 C Tmax

Prospect Evaluation

Source Rock EvaluationThe main source materials for hydrocarbon are the vegetal debris, including those of phytoplankton, marine and terrestrial algae as well as lipid rich land plant remains.

Application of Organic Matter

• Quality of Organic Matter• Quantity/Richness of OM• Thermal Maturation

Organic Matter Types• Structured terrestrial organic

matter (Telinite)• Spores and pollen (Sporonite)• Charcoal (Fusinite) • Biodegraded terrestrial organic

matter (Telocollinite)

Organic Matter Types• Biodegraded aqueous organi c matter • Amorphous organi c matter (Micrinite) • Finely divided organic matter

(Organic matter of bacteri al origin )• Grey amorphous organi c matter

(Corpocollinite)• Structured mari ne organic matter (a) Algae

(Alginite),(b) Dinoflagellates and Acritarchs

• Fungal remains (Sclerotinite)• Resin (Resinite)

Structured terrestrial organic matter

This type of organic matter, when altered, forms biodegraded terrestrial organic matter of semi –amorphous type and the amorphous organic matter. These two are important components of sapropelic hydrocarbon generating types.

Structured Terrestrial Wood

Outer covering of Spore/pollen is composed of sporo –pollenin; It is a resistant material and is commonly preserved in sediments. Sporo-pollenin adds to the liquid hydrocarbon potential of these sediments.

Spores pollen

Spores and Pollen

Charcoal

Structured terrestrial woody organic matter by oxidation results into charcoal.This material has no hydrocarbon source potential. Abundance of fusinite material is indicative of oxidizing depositional environment.

Charcoal

Biodegraded terrestrial organic matter

Terrestrial organic matter of vegetal origin, comprising of hard and soft parts of plants (angiosperms, gymnosperms, pteridophytes and bryophytes) is the first product that is degraded to form this type. Several stages of biodegradation have been understood.

Biodegraded Terrestrial

Biodegraded aqueous organic matter

Phytoplankton Thalloid algal matterFilamentous algae

Phytoplankton

Structured Aqueous

Amorphous organic matter

Amorphous organic matter is a completely transformed structureless matter where all recognizable cellular structures have been lost. It is very hard to distinguish the source of this matter , as terrestrial or aquatic. Such matter is spongy and appears porous. It is generally yellowish-brown or orange in colour.

Amorphous

Organic matter of Bacterial Origin

This type of organic matter forms as a result of the conversion of both terrestrial and algal organic matters by fungal and bacterial attack.

Finely Divided Organic Matter

Grey amorphous organic matter

Grey amorphous organic matter is granular or flaky appearance. Granular matter indicates a reducing environment of deposition. Flaky piece of varying sizes are associated with phytoplankton and filamentous algal remains.

Structured marine organic matter

Dinoflagellates, acritarchs, diatoms, radiolarian, red algae constitute this type of organic matter . These are good source of hydrocarbons. Biodegradation and alteration of this material also results into amorphous and semi-amorphous organic matter.

ORGANIC MATTER FACIES

The types of organic matter are broadly classified into : (1) Humic (2) Sapropelic. Humic organic matter are land or terrestrially derived. Sapropelic organic matter is derived both from marine and terrestrial sources.

FACIES % OF TOTAL OM MAIN HC POTENTIAL

I. HUMIC (H) H > 75% (PC)

a. HUMIC – WOOD (H–W) Wood + BDT > Charcoal Very good (gas)

b. HUMIC – CHARCOAL (H–C) Wood + BDT < Charcoal Poor

II. SAPROPELIC (S) S > 75% (PC) Very good (oil)

III. SAPROPELIC HUMIC (SH) H > 50% (PC)

a. SAPROPELIC HUMIC–WOOD (SH–W) Wood + BDT> Charcoal Good (gas)

b. SAPROPELIC HUMIC–CHARCOAL(SH–C) Wood + BDT< Charcoal Marginal (gas)

IV. HUMIC SAPROPELIC (HS) S > 50% (PC)

a. HUMIC SAPROPELIC – WOOD (HS–W) Wood + BDT > Charcoal Good (oil)

b. HUMIC SAPROPELIC–CHARCOAL(HS–C) Wood + BDT< Charcoal Marginal (oil)

Wood = Structured Terrestrial OM, BDT = Biodegraded Terrestrial OM, PC = Pre Condition

Richness of Organic Matter

Rich Total organic Matter 50 -100%Moderate Total organic Matter 25 -50%Poor Total organic Matter 0 -25%

Thermal Maturation

Thermal alteration index (TAI) is based on palynofossils colours. The TAI scale range of 1.00–5.00 proposed by Staplin (1969) is followed. The number assigned to a particular fossil is designated as its thermal alteration index.

Standard Colours of TAI Scale

Evaluation on integration of Parameters• Qualitative Aspect for gas/oil prone OM• Quantitative Aspect for richness of OM• Thermal Maturation• Suitable paleoenvironments for OM

accumulation• Models prepared give a lead in HC

exploration

Hydrocarbon Source Potential

Organic Matter & Conversi on of Kerogen

Controls on total organic matter

• Productivity• Grain size• Sedimentation rate• Oxidation/Reduction

Organic matter: 1%• Kerogen 90%• Bitumen 10%

Post burial chemical evolution of natural combinations of preserved organic debris conversion into

KEROGEN

Hydrogen: Carbon and Oxygen: Carbon contents of common organic and palynological types.

Post depositional alteration of

KEROGEN

into

BITUMEN

What happens when we subject kerogen to subsurface conditions?KEROGEN

Diagenesis

Catagenesis

Metagenesis

Shallow subsurfaceNormal pressure and temperatureReleased: CH4, CO2, H2O• Overall decrease in O• Overall increase in H and C

Deeper subsurfaceIncreased pressure and temperatureReleased: oil & gas• Overall decrease in H and C

MetamorphismHigh temperature and pressureOnly C remains: becomes graphite

THERMAL STAGES OF BITUMEN GENERATION :DIAGENESIS l ow-temperature/bac terial alteration CATAGENESIS intermediate-temperature alteration METAGENESIS high-temperature/pre metamorphi c alteration

PALYNOFOSSILS• SPORES• POLLEN (Gymnosperms &

Angiosperms)• DINOFLAGELLATES• ACRITARCHS• FUNGI• CHITINOZOA

(contd.)

PALYNOFOSSILS• SCOLECODONTS• SILICOFLAGELLATES• DIATOMS• CALCAREOUS ALGAE• CALC. NANNOFOSSILS• ORGANIC MATTER

PROCESSING TECHNIQUES

• Rock Samples -(cores/cuttings)

• Powdering• Treatment with Acids• Obtain Organic Residue• Slide Preparation

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . .

ROCK SAMPLE

POWDERING OFSAMPLE

TREATMENTWITH HCL

TREATMENTWITH HF

HEAVY LIQUIDSEPARATION

RESIDUE MIXED WITHPOLYVINYL ALCOHOL

DRYING OFRESIDUE BY SPREADING ON COVERSLIP

SLIDE MOUNTINGON HOTPLATE

AT 100 C

SLIDE READYFOR STUDY

O

FLOW CHART FOR PROCESSING OF SAMPLES FOR ORGANIC MATTER

. . . . . . . . . . . .

Slide No.1 depth 1200-1205mKG

-1

. . . . . . . . . . . .

CENTRIFUGE

CENTRIFUGE

Commonly Used Maturation Parameters:

Vitrinite Reflectance

Liptinite Fluorescence

Thermal Alteration Index

Spore Coloration Index

Tmax

Time Temp Index (TTI)

Oil Window based on various Maturation indicators

Indicators of HC Maturation:

Vitrinite Reflectance

&

Liptinite Fluorescence

AOM matrix showing strong but heterogeneous fluorescence

Palynomorphs fluorescing,matrix of autochthonous (plankton-derived) AOM remains predominantly non-fluorescent

AOM matrix showing moderate and heterogeneous fluorescence

Fluorescent organic matter

Ro SWL(nm) TAI Ro SWL(nm) TAI0.30 460 2.00 1.26 3.150.34 475 2.10 1.30 3.200.38 550 2.20 1.33 3.250.40 575 2.25 1.36 3.300.42 2.30 1.39 3.350.44 2.35 1.42 3.400.46 2.40 1.46 3.450.48 585 2.45 1.50 655 3.500.50 590 2.50 1.62 3.550.55 2.55 1.75 3.600.60 600 2.60 1.87 3.650.65 2.65 2.00 3.700.70 2.70 2.25 670 3.750.77 610 2.75 2.50 3.800.85 2.80 2.75 3.850.93 2.85 3.00 3.901.00 2.90 3.25 3.951.07 2.95 3.50 700 4.001.15 630 3.00 4.00 4.001.19 3.05 4.50 4.001.22 3.10 5.00 4.00

Relation between Vitrinite Reflectance (Ro),SWL and Thermal Alteration Index (TAI)

Initiation and progression of Bitumen generation

as related toKerogen type

Incipiently mature with Bitumen Formation

Light coloured immature OM

Mature OM with Bitumen Formation

Volume increase enhances both fracturing potential and pressure drive leading to Migration & Accumulation.

Source rock transformation ratio, Accumulation and Oil Composition in reservoirs

HC source potential profile in a well

Ø Determination of organic matter types, total organic matter and maturation for hydrocarbon source potential.

Ø The source rock parameters integrated with paleoenvironment, age, structure and basin configuration for identification of source rock potential facies in relation to geological and geochemical parameters for better understanding of source depocentres.

Ø To know the timing and duration of generation of hydrocarbons based on the subsidence history curves and time temperature index (TTI) plots.

Application of source rock palynological studies

Relationship of Palynofacies and Geochemical parameters

HI OI

Sapropelic >1.45 >850 10~30 Algal; amorphous

Humic Sapropelic 1.35-1.45 650-850 20-50 Amorphous;minor terrestrial

Sapropelic Humic 1.15-1.35 400-650 30-80 Amorphous;common terrestrial

Pyrolysis YieldPalynofacies H/C at vRo ~0.5

Dominantorganic matter

SapropelicHumic-Wood

0.95-1.15 250-400 40-80 Mixed;some oxidation

Humic Wood 0.75-0.95 125-250 50-150 Terrestrial; some oxidation

Sapropelic Humic-Charcoal

0.60-0.75 50-125 40-150+ Oxidised;reworked

HumicCharcoal

<0.60 <50 20-200+ Highly oxidised; highly bioturbated

Fibrous AOM, massive AOM, grey amorphous with pyrite (after Batten, 1996)

Phytoclasts, wood, cuticle, algal filaments and overmature AOM (after Batten, 1996)

• Qualitative Aspect for gas/oil prone Organic Matter

• Quantitative Aspect for richness of Organic Matter

• Thermal Maturation• Suitable paleoenvironm ents for Organic Matter

accumulation• Models prepared give a lead in HC exploration

Parameters for evaluating source potential

Burial History Curve, TTI, OM Facies, TOM, TAI and source potential in w ell RNL

PALEO-CENE OLIGO

PLIO-REC

Ma

120

110

100

90 80 70 60 50 40 30 20 10 0

30oC

40 oC

50 oC

60 oC

70 oC

90 oC

oC100

110 oC

CRETACEOUS EOCENE MIOCENE

80 oC

LR UP L UP

400m

800

1200

1600

2000

2400

2800

3200

3400

SHIYALI CL ST.VANJIYUR SST.

TITTACHERIFM.

NIRAVI FM.

KARAIKAL SH.

KAMALAPURAM FM.

PORTONOVOSH.

BVG FM.STP SH.

ANDIMADAMFM.

MADANAM LST..

-.-.-.-.-.-

NN

LM

FM.

STP

SH.

POR

TON

OVO

SH

.BV

G

FM.

AND

IMAD

AM F

M.

FM OM

FAC

IES

SAPROPELIC HUMIC-

CHARCOAL

HUMIC SAPROPELIC -

CHARCOAL

SH-C

HUMIC-CHARCOAL

KDV

NNLM FM.

TOTA

L O

MR

ICH

L M U L U L M U

SAPROPELIC HUMIC-

CHARCOAL

POO

R-

MO

D

MOD

RIC

H

TAI

2.25

2.75

+2.

75

TTI=15

TTI=61

TTI=108

SOU

RC

E PO

TEN

TIAL

MO

D -

GO

OD

MOD

POO

R

MOD

MO

D -

GO

OD

2.50

POO

R

120 oC

RNL

Seq.-1 started generation of hydrocarbon since upper most OligoceneSeq.-2 initiated generation since Early Miocene

SOURCE POTENTIAL

POOR

MOD-GOOD

VANJIYUR SST

MADANAM LST.

TIRUTURAIPUNDI SST

ANDIMADAM FM

STP SH

+

+

+

+

+

+

+

TITTACHERI FM

+

+KOMARAKSHI SH

SATTAPADI SHALE

KAMALAPURAM FORMATION

TP-A NG-A NR-A

TIRUPPUNDI FORMATION

SATTAPADI SHALE

IMM

ATU

RE

Source rock Potential facies in Nagapattinam Subbasin, Cauvery Basin

KARAIKAL

NAGAPATTINAM

0 10Km

wells studied

TP-A

NG-A

NR-A

Age

Form

atio

n

Dep

th (m

)

Sam

ple

Posi

tion

Source Rock PalynologyOrganicMatterFacies

TotalOrganicMatter TA

I

Dep

.En

v. SourcePotential

Geochemical Parameters(Rao et al., 1988)

TOC T Max. S2

Pasa

rlapu

di F

orm

atio

n

Low

er E

ocen

e

Pala

kollu

Shal

e

BMP Lst.M

.Eo

c.

3000

2900

2800

2700

2600

2500

2400

2300

2200

2100

2000

Humic-Wood

Rich

Rich

Rich

Moderate-Rich

Mainly Sand Poor Organic Matter

Humic SaproCharcoalHumic-Charcoal

2.25

2.50

2.75

Inne

r to

Mid

dle

Ner

itic

Poor

Good for Gas

Poor

Marginal forOil and Gas

2.00

1.00

1.50

2.503.503.00

3.003.504.00

430

443

446

452

0.63

–2.

990.

76 –

10.6

Palynofacies, TOM, maturation and source potenti al of Palakollu Shale and Pasarlapudi Formation in well PSP

0.50

0.30

Palynofacies, TOM, maturation and source potential of Chintalapalli Shale, Palakollu Shale and Pasarlapudi Formation in well MTP

Age Formation

Sam

ple

posi

tion

Depth(m)

SH-W

T O M TAIDepo.Env.

Geochemical data(Philip et al., 1986

TOCTMax & vRo

Late

Cre

tace

ous

(Maa

stric

htia

n)

Chi

ntal

apal

li Sh

ale)

Pasa

rlapu

di

PalakolluShale

Razole

450044004300420041004000390038003700360035003400330032003100300029002800270026002500240023002200

O MFacies

Poor-Moderate

Sapropelic Humic-Charcoal

Humic Sapro-pelic - Wood

Humic-Charcoal

Poor

Sapropelic Humic-Charcoal

Humic-Charcoal

Humic-Charcoal

SH-C

Poor

Moderate

Rich

Moderate

Poor-Moderate

Rich

Moderate2.

002.

25

Mid

dle

–In

ner N

eriti

cO

uter

Ner

itic

2.50

Upp

er B

athy

al

2.75

Poor

Source Potential

Poor

Marginalfor Gas

Poor

Marginalfor Gas

Poor

Marginalfor Gas

436-

308

436-

275

445-318

468-

237

0.76

Source Rock Palynology

0.75

0.90

1.001.50

1.00

1.50

1.502.50

1.50

2.000.900.750.80

4.003.502.50

2.00

0.75

1.00

0.80

0.90

2.00

Late

Cre

tace

ous

(Maa

stric

htia

n)

EarlyPalocene

Late

Pale

ocen

eEa

rly-M

iddl

e Eo

cene

Narasapur Claystone

0

1000

2000

3000

4000

5000

Chintalapalli Shale

Narasapur Claystone

Matsyapuri Sandstone

Pasarlapudi Formation

Palakollu Shale

Razole Formation

Dep

th in

met

ers

0 25 50 75 km

SWNE

Rajahmundry Sandstone

Lithofacies distribution across profile B -B’

B B’BMP PSP NSP GS5GS8RZLCTP

Dep

th in

met

ers

Narasapur Claystone

B B’0

1000

2000

3000

4000

5000

SWNE

Source potential facies across profile B-B’

Good for oil & gas

Moderate for oil & gas

Moderate for gas

BMP PSP NSP GS5GS8RZLCTP

Chintalapalli Sh

Razole Fm

Matsyapuri Sst

Pasarlapudi Fm

Rajahmundry SstNarasapur Cl

0 25 50 75 km

SECTION ALONG A – A’ SHOWING PALEOENVIRONMENTS

FLUVIAL

LOWER DELTA

MARGINAL MARINE

INNER NERITIC

INNER-MIDDLE NERITIC

MIDDLE-OUTER NERITIC0 10km

0m

1000m

FLUVIAL-PARALIC

KMG-A MDP-A DKR-A END-AA A’

KMG-A MDP-AEND-ADKR-A

Bay of Bengal

TANUKU HORST MANDAPETA SUBBASIN DRAKSHARAMA RIDGE

KMG-A MDP-A DKR-A END-AA A’

HUMIC SAPROPELIC-CHARCOAL

0 10km

0m

1000m

KMG-A MDP-AEND-ADKR-A

Bay of Bengal

HUMIC-CHARCOAL (H-C)

SAPROPELIC HUMIC -CHARCOAL (SH-C)

SAPROPELIC HUMIC- WOOD (SH-W)

HUMIC SAPROPELIC-WOODSAPROPELIC

TANUKU HORST MANDAPETA SUBBASIN DRAKSHARAMA RIDGE

SECTION ALONG A – A’ SHOWING PALYNOFACIES

MODERATE

MODERATE - RICH

RICH

0 10km

0m

1000m

POOR - MODERATE

KMG-A MDP-A DKR-A END-AA A’

KMG-A MDP-AEND-ADKR-A

Bay of Bengal

POOR ORGANIC MATTER

TANUKU HORST MANDAPETA SUBBASIN DRAKSHARAMA RIDGE

SECTION ALONG A – A’ SHOWING RICHNESS OF ORGANIC MATTER

SECTION ALONG A – A’ SHOWING SOURCE ROCK POTENTIAL FACIES

A’

TAI = 2.50

0 10km

0m

1000m

KMG-A MDP-A DKR-A END-AA

KMG-A MDP-AEND-ADKR-A

Bay of Bengal

P O O R S O U R C E P O T E N T I A L

MARGINAL FORGAS/OILMODERATE FOR GASMODERATE FOR OIL & GASMODERATE-GOOD FOR GAS

MODERATE-GOOD FOR OIL & GAS

GOOD FOR GAS

GOOD FOR OIL & GAS

LATE CRETACEOUS

EARLY CRETACEOUS

MID-LATE TRIASSIC

MID. TRIASSIC - PERMIAN

GAS PROD.

HYDROCARBON SOURCE POTENTI AL

Source potential facies in Kakinada area, Krishna-Godavari Basin

:s:s s s s s 11003200 s s m

:s:s s s:s:s s s:s:s s s s s:s:s ss s s s s s 1220

s ss s s s s ss s s

s s s s 13003400 s s s

s s s s s ss s

s s s s s s 1405s s s

s s s ss s s

s s s ss s s

s s s s s s 15003600 s s s

s s s s s ss s

s s s s s ss s

s s s ss

s s s ss s

s s s s 17003800 s

s s s ss s

s s s ss s

s s s ss

2120 s s s s2140 s s2160 :s:s s s 19002180 :s:s

4020 2200 :s:s2220 :s:s2240 :s:s2260 :s:s22802300 :s:s

:s:s:s:s:s:s 2100

B a

r

r e

m

i a

n

-

A

p

t I

a

nLa

te A

ptian

- Al

bian

Late

Albi

an -

Ceno

man

ian

Mod.-Goodfor gas

Top of sequence order VIIIDATUM LINEBKDBKASBKAGSZ

16001900

2100

1700

1500

1360Moderate

for gas

11000

1300

VIII

VIII

VIII

VII

VIII

VII

VII

VI

VI

VI

V

V

V

VII

IVIV

IV

VI

Mod.for oil & gas

Moderate for gas

Poor

ANNAVARAM

PITHAPURAM

KAKINADA

YANAM

BKA

SBKA

GSZ

BKD

0 Km20

FLUORESCENCE STUDIES

v Spectral wavelength is measured on Leitz MPV-3Fluorescence Microscope Spect rophotometer

v Polospores, organic matter excited by ultra violetlight of 200-400nm spectral wavelength range andemission spect ra of 400-700nm range is observed

v The maximum spectral wavelength of light emittedby specimen is considered f or calculat ion ofmaturity

v Boreholes drilled along the Hinge Zone and west of it are considered for plotting maturation profilesto interpret source depocent res

Maturation profile on the basis of Spectral wavelength in Bengal Basin during M iocene

Bihar

Orissa

N

0 20 40 60 Km

Ichapur-A

Ichapur-B

Karimpur-A

Abhay-AGalsi-BGalsi-C Palashi-A

Mainagar-A

Chandkuri-A

SWL570nm

SWL 480-530nm

SWL 560-575nm

SWL<550nm

SWL 560-570nmSME-A

SWL560-580nm

SWL 575nmImmature phase

Immature phase in all the wells during Miocene

Maturation during Maturation during MioceneMiocene

Maturation profile on the basis of Spectral wavelength in Bengal Basin during Oligocene

Bihar

Orissa

N

0 20 40 60 Km

Ichapur-A

Ichapur-B

Karimpur-A

Abhay-AGalsi-BGalsi-C Palashi-A

Mainagar-A

Chandkuri-ASWL570-585nm

SWL <570nm

SWL 580-585mm

SWL 570-585nm

SWL 585-590mm

SWL 535nm

SME-A

Immature phase

Early phase of maturation

Maturation during Maturation during OligoceneOligoceneØImmature phase in the wells Galsi-B, C, Mainagar-A, Palashi-A and Abhay-A Ø Early phase of maturation in the wells SME-A, Chandkuri-A, Ichapur-A, B and Karimpur-A

Maturation profile on the basis of Spectral wavelength in Bengal Basin during Eocene

Bihar

Orissa

N

0 20 40 60 Km

Ichapur-A

Ichapur-B

Karimpur-AAbhay-A

Galsi-BGalsi-C Palashi-A

Mainagar-A

Chandkuri-A

SWL>600nm

SWL 540-570nm

SWL 590-600nm

SWL>600nm

SWL590-600nm

SWL590nm

SWL<570nm

SME-A

Immature phase

Initiation of generationof hydrocarbons

Maturation during Maturation during EoceneEocene

ØImmature phase in the wells Galsi-B, C

ØEarly phase of maturation in the wellsMainagar-A, Palashi-A

ØInitiation of generation of hydrocarbons in the wells SME-A, Chandkuri-A, Ichapur-A, B, Abhay-A and Karimpur-A

Maturation profile on the basis of Spectral wavelength in Bengal Basin during

Paleocene

Bihar

Orissa

N

0 20 40 60 Km

Ichapur-AIchapur-B

Karimpur-AAbhay-A

Galsi-BGalsi-C Palashi-A

Mainagar-A

Chandkuri-A

SWL>630nm

SWL 570-580nm

SWL 580-590nm

SWL>600nm

SWL 585-590nm

SME-A

Mature phase

Early phase of maturation

MaturationMaturationduring Paleoceneduring Paleocene

Ø Early phase of maturation in the wellsGalsi-B, Mainagar-A, Palashi-A

Ø Initiation of generation of hydrocarbons in the wells Abhay-A and Karimpur-A

Ø Mature phase in Chandkuri-A

Maturation profile on the basis of Spectral wavelength in Bengal Basin during Cretaceous

Bihar

Orissa

N

0 20 40 60 Km

Ichapur-A

Ichapur-B

Karimpur-A

Abhay-AGalsi-BGalsi-C Palashi-A

Mainagar-A

Chandkuri-A

SWL630-655nm

SWL 590-600nm SWL590-600nm

Mature phase

Initiation of generationof hydrocarbons

SME-A

MaturationMaturationduring Cretaceousduring Cretaceous

Ø Initiation of generation of hydrocarbons in the wells Galsi-B, Mainagar-A, Palashi-A

ØMature phase in Chandkuri-A

v Maturation profiles drawn for the area alongthe Hinge Zone and west of it for Cretaceousto Miocene

v Maturation profiles indicate, organic matternear the Hinge Zone has reached maturi tylevel earlier as compared to that i n thearea far west of Hinge Zone

Interpretation on Maturation Profile

Evaluation on integration of Parameters• Qualitative Aspect for gas/oil prone OM• Quantitative Aspect for richness of OM• Thermal Maturation• Suitable paleoenvironments for OM

accumulation• Models prepared give a lead in HC

exploration

Hydrocarbon Source Potential