hydrodynamic trapping

geology

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June 29, 2026

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Hydrodynamic trapping is a rare geological phenomenon where petroleum accumulates not in a typical structural or stratigraphic trap, but due to a "water block". This occurs when high water saturation in low-permeability sediments significantly reduces hydrocarbon permeability to near zero. Consequently, the petroleum is pushed down the structural dip of a sedimentary bed, accumulating below the water in the formation, rather than rising to the top of a trap as it normally would. This contrasts with standard petroleum traps, which rely on impermeable cap rock to prevent the upward or lateral escape of oil and gas.123

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petroleum
Traps
A rare exception is hydrodynamic trapping, in which high water saturation of low-permeability sediments reduces hydrocarbon permeability to near zero, resulting in a water block and an accumulation of petroleum down the structural dip of a sedimentary bed below the water in the sedimentary formation.
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A rare exception is hydrodynamic trapping, in which high water saturation of low-permeability sediments reduces hydrocarbon permeability to near zero, resulting in a water block and an accumulation of petroleum down the structural dip of a sedimentary bed below the water in the sedimentary formation.
Read More