The AAPG/Datapages Combined Publications Database
AAPG Bulletin
Figure
AAPG Bulletin; Year: 2023; Issue: July DOI: 10.1306/10242221068
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Figure 17.
(A) The total hydrocarbon expulsion driven by buoyancy + overpressure at different source rock permeabilities (k ). A small decrease of oil volume causes a large pressure drop in the source rock because of the low oil compressibility. As a result, the contribution from overpressure is only 10%, and most of the oil is expelled in a very short period of time (a step increase). (B) The present pore pressure in the Tuwaiq Mountain Formation. The time of emergence of isolated hydrocarbon (HC) clusters is between 20 and 13 Ma. If these clusters formed at 20 Ma, the present-day pore pressure would vary between 57 and 64 MPa. If they had formed at 13 Ma, the present-day pore pressure would vary between 45 and 47 MPa. Depending on the oil-to-gas conversion efficiency and the time when the formation-spanning cluster is disconnected, the present-day pore pressure ranges between 45 and 64 MPa.
Figure 17.
(A) The total hydrocarbon expulsion driven by buoyancy + overpressure at different source rock permeabilities (