Module 10b

Question 1

What are the 3 types of kerogen?

Answer 1

Types I & II: primarily residues of small marine organisms & algae. Tend to produce oil and gas.

Type III: residues of land plant material. Tend to produce gas.

Question 2

Explain the conversion of kerogen to oil and gas

Answer 2

1. bacteria convert to organic material into the waxy substance called kerogen
2. Happened during burial of sediment: temp increases and the composition gradually changes.
3. Results in the continuous increased in the carbon content of kerogen

Question 3

What are the 3 successive temperature stages?

Answer 3

Diagenesis
Catagenesis
Metagenesis

Question 4

When does diagenesis stage form?

Answer 4

in the shallow depths and releatively low temperatures. At this stage, the source rock is considered IMMATURE

Question 5

What is catagenesis?

Answer 5

is the formation stage of oil and wet gas. This is the main zone of oil generation.

Question 6

What is metagenesis?

Answer 6

The stage in which dry gas is formed and the cracking of heavy hydrocarbon occurs. (methane and C are the end products of this stage)

Question 7

What are the temperature ranges of diagenesis, catagenesis and metagenesis?

Answer 7

diagenesis: up to 60C
catagenesis: oil- 60-176C, wet gas (176-225C)
metagenesis: dry gas- 225-315C, graphite > 315C

Question 8

What is the normal temperature increase normally for each km of depth from the surface of the earth?

Answer 8

25C for each km

Question 9

What is reservoir compartmentalization?

Answer 9

natural division of petroleum, accumulations into a number of individual compartments.

Question 10

How is compartmentalization commonly cause?

Answer 10

faulting, diapirism, and by depositional patterns

Question 11

What is an example of a compartmentalized oil field?

Answer 11

Supergiant Canadian Hibernia oil field (>1 billion barrels OOIP)

Question 12

What are 6 methods to detect compartmentalization?

Answer 12

HC geochemistry
different HC/water interfaces
seismic
pressure analysis
shale gouge ratio
radioactive tracers

Question 13

Name 4 types of fracture analyses

Answer 13

Distribution density & geometry
surface features
relative timing of formation
Geometric relationships

Question 14

Fractures may be detected in wellbores by what 4 methods?

Answer 14

Sophisticated resistivity logs
Sonic logs
Caliper curve
Down-hole oriented cameras

Question 15

What 3 categories can HC drive mechanisms be described under?

Answer 15

Primary recovery
Secondary recovery
EOR

Question 16

What is primary recovery and what are 4 examples?

Answer 16

natural energy found within the reservoir used to lift HC’s.

1. Solution gas drive
2. Gas cap drive
3. Water drive
4. Gravity drainage

Question 17

What is secondary recovery and what are 2 examples?

Answer 17

application of an artificial method to improve the recovery rate when the natural drive weakens

1. Water flooding
2. Gas injection