Seismic data are now used quite often to detect abnormal subsurface pressure. Findings are then employed to design casing and mud-weight programs that facilitate drilling. It is also known that the long-term presence of geopressure can cause changes in rocks that affect their properties as well as those of the core fluids. Research is progressing in this area involving principally geochemistry and well logs.

It is also recognized that reservoirs beneath salt can represent favorable circumstances but also present formidable problems with seismic imaging. Here we note the possibility of analogously favorable reservoirs, but now associated with geopressure further favors having the possibility of seismic detection in advance of the drill.

First, a pressured reaction (especially shale) can constitute a formidable barrier to hydrocarbon leakage much as the case with overlying salt. Next, just as salt having high thermal conductivity more efficiently cools a section below, so thermal eddy currents could produce a similar effect. One obvious consequence of cooling is to slow down processes that destroy porosity and permeability and also affect hydrocarbon maturation which forms oil and ultimately cooks it to carbon.

Lastly, the force driving the upward movement of salt layer bedded from a redirection of the overburden forces squeezing down on the mobile salt. "Squeezing" water from an overpressured zone or leakage may cause similar compaction shielding, also possibly enhancing reservoir quality. Because the case of enhancement associated with geopressure is usually more amenable to seismic imaging, detection and assessment can be accomplished more readily than in the case of sub-salt, particularly if some well control or prior information is available. A case study from offshore Texas predicting and validating such enhancement is discussed.

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