The graph below shows the volume of known petroleum in different regions of the world as estimated in 1997.

Question

The graph shows that most of the known petroleum at the time was located in Region 2, which includes the Middle East and northern Africa.

Based on the large volume of petroleum in Region 2, what kind of activity must have occurred there in the past?
A.
Large amounts of carbon dioxide were released into the air and precipitated back down as petroleum.
B.
Flooding in this area resulted in rapid chemical weathering that created petroleum as rocks were broken down.
C.
Large amounts of organic matter were buried and then trapped by underground rock formations to create petroleum reservoirs.
D.
Mass wasting from northern regions resulted in the deposition of underground petroleum reserves.

Answer 1

The correct answer is:

C. Large amounts of organic matter were buried and then trapped by underground rock formations to create petroleum reservoirs.

This option accurately describes the geological processes involved in the formation of petroleum. Petroleum is typically formed from the remains of ancient marine organisms that were buried under layers of sediment and subjected to heat and pressure over millions of years, leading to the creation of oil reservoirs. The significant volume of petroleum found in Region 2 suggests a long history of such organic material being deposited and preserved in that area.