Petroleum system
Exploring for Oil and Gas Traps | |
Series | Treatise in Petroleum Geology |
---|---|
Part | Traps, trap types, and the petroleum system |
Chapter | Petroleum systems |
Author | Leslie B. Magoon, Edward A. Beaumont |
Link | Web page |
Store | AAPG Store |
The petroleum system is a unifying concept that encompasses all of the disparate elements and processes of petroleum geology. Practical application of petroleum systems can be used in exploration, resource evaluation, and research.
What is a petroleum system?
A petroleum system encompasses a pod of active source rock and all genetically related oil and gas accumulations. It includes all the geologic elements and processes that are essential if an oil and gas accumulation is to exist.
Petroleum describes a compound that includes high concentrations of any of the following substances:
- Thermal and biological hydrocarbon gas found in conventional reservoirs as well as in gas hydrates, tight reservoirs, fractured shale, and coal
- Condensates
- Crude oils
- Natural bitumen in reservoirs, generally in siliciclastic and carbonate rocks
System describes the interdependent elements and processes that form the functional unit that creates hydrocarbon accumulations.
Elements and processes
The essential elements of a petroleum system include the following:
- Source rock
- Reservoir rock
- Seal rock
- Overburden rock
Petroleum systems have two processes:
- Trap formation
- Generation–expulsion–migration–accumulation of hydrocarbons
These essential elements and processes must be correctly placed in time and space so that organic matter included in a source rock can be converted into a petroleum accumulation. A petroleum system exists wherever all these essential elements and processes are known to occur or are thought to have a reasonable chance or probability to occur.
Petroleum system investigation
A petroleum system investigation identifies, names, determines the level of certainty, and maps the geographic, stratigraphic, and temporal extent of a petroleum system. The investigation includes certain components:
- Petroleum–petroleum geochemical correlation
- Petroleum–source rock geochemical correlation
- Burial history chart
- Petroleum system map
- Petroleum system cross section
- Events chart
- Table of hydrocarbon accumulations
- Determination of generation–accumulation efficiency
See also
- The petroleum system concept
- Identifying a petroleum system
- Naming a petroleum system
- Geographic, stratigraphic, and temporal extent
- Size of a petroleum system
- Mapping a petroleum system