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.
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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:
'''Petroleum''' describes a compound that includes high concentrations of any of the following substances: