Oleh:

RAGIL PRATIWI

GEOSERVICES

Introduction to Petroleum Geochemistry and its Significance in Hydrocarbon Exploration and How to Get Your Scholarships Abroad?

UNDIP SHARING SESSION

Semarang, 20th June 2015

Biomarker Outline

• How does petroleum form?

• What is biomarker?

• What is biomarker for?

• How can we understand oil – oil and oil – source rock correlations?

2

Petroleum Originates From Organic-Rich Source Rocks 3

Peters (2010)

Biomarkers

• Biomarkers are compounds that characterize certain biotic sources and retain their source rock correlations to assess their source information after burial sediment.

Meyers (2003)

• It is used for oil – oil and oil – source rock correlations to assess the source organofacies, kerogen types, and the degree of thermal maturity.

Waples and Machihara (1991)

4

Biomarkers: Micro–Microfossils Establish Petroleum Systems 5

Peters (2010)

Information can be

obtained from biomarkers :

a. type of organic matter

b. type of lithology

c. environment of

deposition

d. age of source rock

e. maturity

f. alteration history

Satyana (2014)

Biomarkers (Biological Markers)

Biomarker

GC

Alkanes Isoprenoids

GCMS

Saturates Aromatics

CPI Ph/Ph ratio Isoprenoids / n alkanes ratio

Triterpane Sterane

C27, 28, 29 MPI

Oleanane Index

Gammacerane

Index Ts/Tm Ratio

6

Gas Chromatography

• Gas Chromatography (GC) is used to separate volatile components of a mixture.

• The injector is set to a temperature higher than the components’ boiling points.

7

Gas Chromatography : n – Alkanes ratio

Carbon Preference Index

CPI shows source input and maturity

CPI = 0.5 x ΣC25 – C35 (odd number carbon)

ΣC24 – C34(even number carbon)

High CPI = immature source rocks from land – plant input

Low CPI = mature source rocks from marine input

8

Peters, et all. (2005)

Gas Chromatography : Isoprenoid ratio

Pristane (iC19) / Phytane (iC20)

(Pr / Ph)

High Pr/Ph ( > 3.0 ) = terrigenous organic matter under oxic condition

Low Pr/Ph ( < 0.8 ) = hypersaline or carbonate organic matter under

anoxic condition

9

Peters, et all. (2005)

Isoprenoids / n-Alkanes Ratios 10

OIL C

OIL B

OIL A

0.07

0.7

7

1 10

Pr/n

C1

7Pr/Ph

HIGHLY ANOXICANOXIC TO SUBOXIC

LACUSTRINE OR MARINEOXIC TERRESTRIAL

contamination

Selected Ion Monitoring GCMS: Characteristic Fragments 11

Peters (2010)

Selected Ion Monitoring GCMS: Characteristic Fragments 12

Peters (2010)

Mass Chromatograms Show Peaks Not Visible on GC 13

Peters (2010)

14 Biomarkers as Source and Paleoenvironment Indicators

Hunt (1996)

15 Biomarkers as Source and Paleoenvironment Indicators

Hunt (1996)

STERANES 16

Waples and Machihara (1991)

Steranes inherited directly from higher

plants, animals, and algae.

Measured by GCMS m/z 217 and m/z 218.

Steranes : C27 – C29 Plot Helps Establish Petroleum Systems in West Siberia

17

Triterpanes 18

Waples and Machihara (1991)

- Triterpanes inherited directly from bacteria.

- These compounds arepotentially powerful markers for diagenetic conditions.

- Measured by GCMS m/z 191.

Triterpanes : Oleanane 19

Oleananes are thought to be derived from a variety of terrestrial precursors,

especially angiosperms that produce abundant resin.

(Ekweozor and Udo, 1988;

Riva et al., 1988)

Because angiosperms are

believed to have evolved in

Late Cretaceous time, the

absence of oleananes in

Lower Cretaceous and older

sediments is understandable.

(e.g., Bagge et al., in press)

Triterpanes : Gammacerane 20

Gammacerane is believed to be derived from tetrahymanol. Tetrahymanol

occurs in protozoa. (Venkatesan, 1989; ten Haven et al.,1989).

Gammacerane is highly

spesific for water – column

stratification (commonly due

to hypersalinity) during source

– rock depositional position

Gammacerane is useful to

distinguish petroleum family.

4Peters and Moldowan (1994)

Caelho, et all. (2008)

21

Visser (2010) in Satyana (2014)

22

Visser (2010) in Satyana (2014)

23

Visser (2010) in Satyana (2014)

Biomarker as Maturity Parameter

24

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0

C29 aaa

S/aaa

R S

teran

es

C29 abbR+S/aaaS+R Steranes

Crossplot of Sterane Maturity Parameters

oil A

oil B

oil C

peakmature

late matureor facies effect

Maturity calibrated from Mesozoic

clastic sediments, after Miles, 1989

immature

early mature

0.05

0.5

0.1110C

30

Mo

reta

ne/H

op

an

eTm/Ts

Crossplot of Triterpane Maturity Parameters

oil A

oil B

oil C

peak

mature

late

maturepost

mature

Maturity ranges for clastic source rocks after Miles, 1989

Both parameters are relatively high in coals/coal-sourced oils

terrestrial plant influence

immature

early mature

After Milles (1989)

Biomarker as Maturity Parameter 25

F2 F1 MPI-1MPR-2

0.5

0.6

0.7

0.8

0.9

1.0

1.1

1.2

1.3

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0

Eq

uiv

ale

nt

Ro

.

MP Index

OIL A

OIL B

OIL C

peak mature

late mature

After Radke et al, 1983, 1984

and Kvalheim et al, 1987

early mature

often unreliable

METHYLPHENANTRENE INDEX

Biodegradation 26

Biodegradation 27

Wenger, et all (2002)

Biomarkers as Oil – Oil and Oil Source Correlations 28

Satyana (2014)

Questions that you like to be answered by

biomarker work:

a. Which source rock correlates with this oil?

(oil –source rock correlation)

a. Are these oils from the same source rock?

(oil –oil correlation)

Biomarkers for Oil - Source Correlation 29

Bissada, et all. ( 1992) in

Satyana (2014)