Hydrocarbon accumulation and entrapment under hydrodynamic conditions

2 Hydrocarbon accumulation and entrapment under hydrodynamic conditions 

Hydrodynamic conditions affect the sealing capacity of a rock or fault, and consequently influence the holding capacity for hydrocarbons of hydrostatic structural, stratigraphic and combination traps. In addition, hydrodynamic conditions may create additional regions of minimum potential energy for separate phase hydrocarbons, i.e. purely hydrodsmamic trapping positions. 

Hubbert (1967) described a trap for either oil or gas as an underground region of low potential for the respective fluid, which is either completely enclosed by equipotential surfaces and regions of higher potential, or else jointly enclosed by higher equipotential surfaces and an impermeable boundary. The potential of a unit mass of separate phase hydrocarbons in water-saturated rock under hydrodynamic conditions is given by 

As outlined in Chapter 4, the net driving force for separate phase hydrocarbon migration is (Equation 4.11). 

Hydrodynamic influence on holding capacity of conventional hydrostatic traps 

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