PETROLEUM SYSTEM

THE PROCESSES

DEFINITION

THE ELEMENTS

Accumulation order in reservoir rock

  • depends on density of hydrocarbon component

The driving force is TEMPERATURE & PRESSURE

1. Source Rock (sedimentary rock at depth at considerable time &T)
Ex:

  • Shales
  • Sandstones
  • Carbonates

2. Reservoir Rock

  • Oil & gas accumulates here
  • Must hv features of porosity and permeability

3. Seal Rock

  • Oil & Gas can't move effectively through it
    -Ex: Mudstone, Claystone

4. Migration Route

  • route for oil & gas moves from source rock to trap
    Ex: fault / fracture

1. Generation

3. Migration

4. Accumulation

Formation of hydrocarbon (oil) in source rock.

Source rock contain dead plants & animals for millions of yrs

Dead plants need high T, P & depth to transform to HCs

Movement of HCs through porous and permeable rock

High T, HCs migrate from source rock to reservoir rock

  • Gathering of oil & gas in reservoir rocks
  • Oil & gas found in traps in reservoir rock
  • cap rock / seal rock (prevent oil & gas from escaping)

5. Trap

  • Configuration that concentrates oil & gas into accumulation
  • Ex: Stratigraphy trap, structural Trap

Combination between geologic components & HCs generation/ accumulation processes

    1. water is heavy
    1. oil is light
    1. gas lighter
      cap rock

FARHAH NABILAH BINTI FADZIL
E18A0028

5. Preservation / Recovery

  • Economic value oil & gas

2. Expulsion

  • Has gas & oil window

SEDIMENTARY BASIN?

Only place for petroleum generation