ABSTRACT
Petroleum, heavy oil, and tar sand bitumen are not usually found where the precursors were laid down, but in reservoirs where accumulation occurs after it has migrated from the source rocks through geologic strata. In addition, the theory that the petroleum precursors form a mix that is often referred to as “protopetroleum” (also referred to as “primordial precursor soup” or “petroleum porridge”) is an acceptable generalization (Speight, 2014). And the molecular types in any specified fraction are limited by the nature of the precursors of petroleum, their chemical structures, and the physical conditions that are prevalent during the maturation (conversion of the precursors) processes.
