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Line 27: − The following figure is a simple example of a fault plane profile. The sand reservoirs in the hanging wall (dark gray) and footwall (light gray) are shown on the same cross section drawn in the plane of the fault. In this example, all hydrocarbon accumulations (black) are limited by JLLPs (juxtaposed lithology leak points). Hydrocarbons cross-leak from the footwall sands into the hanging wall sands. − + + + − The fault plane profile in the following figure is similar to the profile in Figure 10-15 except that the fault is cross sealing at the fault/reservoir intersection in the lowest foot-wall sand. Despite a sand/sand juxtaposition at the crest of this reservoir, the fault traps hydrocarbons at a cross sealing segment. Higher sands continue to cross-leak. The percent fill of the lowest sand is limited by either the P<sub>d</sub> of the fault zone, the charge volume, or the top seal—not a JLLP. − + + +
Fault plane profile construction (view source)
Revision as of 22:32, 3 February 2014
, 22:32, 3 February 2014no edit summary
==Example: FPP of cross-leaking fault==
==Example: FPP of cross-leaking fault==
[[file:evaluating-top-and-fault-seal_fig10-15.png|thumb|{{figure number|10-15}}See text for explanation.]]
[[file:evaluating-top-and-fault-seal_fig10-15.png|thumb|{{figure number|1}}See text for explanation.]]
[[:file:evaluating-top-and-fault-seal_fig10-15.png|Figure 1]] is a simple example of a fault plane profile. The sand reservoirs in the hanging wall (dark gray) and footwall (light gray) are shown on the same cross section drawn in the plane of the fault. In this example, all hydrocarbon accumulations (black) are limited by JLLPs (juxtaposed lithology leak points). Hydrocarbons cross-leak from the footwall sands into the hanging wall sands.
The fault cross-leaks along its entire surface at sand/sand juxtapositions. At each sand/sand juxtaposition, a JLLP spills the hydrocarbons across the fault. There is sufficient charge to fill all closures to a fault-dependent leak point. Potential reservoirs with JLLPs at the crest are dry. The percent fill for other sands is constrained by the JLLPs.<ref name=ch10r2 /> If bed dips in the hanging wall allow entrapment against the fault, hydrocarbons could be trapped in both the hanging wall and footwall reservoirs. With sufficient charge, common hydrocarbon contacts could exist.
The fault cross-leaks along its entire surface at sand/sand juxtapositions. At each sand/sand juxtaposition, a JLLP spills the hydrocarbons across the fault. There is sufficient charge to fill all closures to a fault-dependent leak point. Potential reservoirs with JLLPs at the crest are dry. The percent fill for other sands is constrained by the JLLPs.<ref name=ch10r2 /> If bed dips in the hanging wall allow entrapment against the fault, hydrocarbons could be trapped in both the hanging wall and footwall reservoirs. With sufficient charge, common hydrocarbon contacts could exist.
==Example: FFP that cross seals, cross leaks==
==Example: FFP that cross seals, cross leaks==
[[file:evaluating-top-and-fault-seal_fig10-16.png|thumb|{{figure number|10-16}}See text for explanation.]]
[[file:evaluating-top-and-fault-seal_fig10-16.png|thumb|{{figure number|2}}See text for explanation.]]
The fault plane profile in [[:file:evaluating-top-and-fault-seal_fig10-16.png|Figure 2]] is similar to the profile in Figure 10-15 except that the fault is cross sealing at the fault/reservoir intersection in the lowest foot-wall sand. Despite a sand/sand juxtaposition at the crest of this reservoir, the fault traps hydrocarbons at a cross sealing segment. Higher sands continue to cross-leak. The percent fill of the lowest sand is limited by either the P<sub>d</sub> of the fault zone, the charge volume, or the top seal—not a JLLP.
For an example of a fault plane profile of a fault in a Gulf Coast field, refer to Figure 10-26.
For an example of a fault plane profile of a fault in a Gulf Coast field, refer to Figure 10-26.