Arrange the following processes from initial to last in the formation of a petroleum deposit:
A. Accumulation B. Generation C. Seepage D. Primary migration E. Secondary migration
Choose the most appropriate answer from the options given below:

Correct option is C

The formation of petroleum deposits involves a sequential process, starting with organic matter generation and ending with accumulation and potential seepage:
1. Generation (B):
· Organic matter buried under sediment undergoes heat and pressure over millions of years, forming hydrocarbons.
· This process occurs in source rocks.
2. Primary Migration (D):
· The hydrocarbons migrate from the source rock into porous carrier beds or rocks due to pressure differences.
3. Secondary Migration (E):
· The hydrocarbons move further through carrier rocks towards traps or reservoirs due to buoyancy forces.
4. Accumulation (A):
· The hydrocarbons are trapped in porous rocks capped by impermeable layers, forming reservoirs.
5. Seepage (C):
· If traps are not sealed properly, hydrocarbons may escape to the surface, causing seepage.
Information Booster: 1. Key Stages in Petroleum Formation:
· Source Rock Formation: Organic-rich sedimentary rocks.
· Kerogen Formation: Organic matter converts to kerogen under heat and pressure.
· Oil Window: Temperature and depth range where oil forms (60-120°C).
2. Types of Traps:
· Structural Traps: Formed by folding or faulting of rocks.
· Stratigraphic Traps: Result from variations in sediment deposition.
3. Petroleum Migration:
· Primary Migration: Movement from source rock to carrier beds.
· Secondary Migration: Movement within carrier beds to reservoirs.
4. Exploration Indicators:
· Seepage on the surface can indicate the presence of hydrocarbons below.