Petroleum Systems

Question 1

List the essential elements of a petroleum system and describe each element

Answer 1

Source rock: a rock with abundant hydrocarbon prone organic matter.
Migration route: Avenues in rock through which oil and gas moves from source rock to trap.
Reservoir rock: A rock in which oil and gas accumulates.
Seal rock: A rock through which oil and gas cannot move effectively.
Trap: the structural and stratigraphic configuration that focuses oil and gas into accumulation.

Question 2

List the essential processes of the petroleum system and describe each system.

Answer 2

Generation: burial of source rock to temperature and pressure regime sufficient to convert organic matter to hydrocarbon.
Migration: movement of the hydrocarbon out of the source rock and towards/into the trap.
Accumulation: a volume of hydrocarbon migrating into a trap faster than the trap leaks, resulting in accumulation.
Preservation: Hydrocarbon remains in reservoir and is not altered by biodegradation or water washing.
Timing: Trap forms before and during hydrocarbon migration.