Thermal Impact of Salt
Published:January 01, 1994
In the previous section (Salt Tectonics and Hydrocarbon Plays), there was a brief discussion of salt movements which could create shapes that serve as hydrocarbon traps. In this section, there is a discussion of the thermal conductivity of salt and the thermal impact the salt may contribute to creating mature hydrocarbons and thermally-induced traps. Note that the section is taken from Yu, et al., 1992.
Salt has a thermal conductivity 2-3 times greater than that of typical sedimentary rocks (O'Brien and Lerche, 1988; Lerche and O'Brien, 1987). Salt bodies in the subsurface act as conduits for heat transport vertically or horizontally. When salt bodies occur in massive diapirs (sheets), with large vertical (horizontal) relief, they provide a path of low thermal resistance for the conduction of heat in the basin. Local thermal anomalies in the vicinity of salt are expected, owing to the focusing and defocusing of heat by salt. The temperature distribution in the basin has a marked impact on the occurrence of oil and gas, especially through the influence of temperature on hydrocarbon maturation. Maturation can be modeled as a first- order chemical reaction, in which the reaction rate doubles with every 10°C rise in formation temperature (Lopatin, 1971); thus, any effect which causes a significant variation in temperature distribution from the regional trend may have a substantial influence on hydrocarbon generation and accumulation in the subsurface.
Here, a two-dimensional fluid flow/compaction model is used, which allows for both thermal conduction and convection
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Seismic Stratigraphy and Hydrocarbon Traps: Louisiana Onshore and Offshore
“Synergisms among tectonics, sedimentation, and climate/sealevel oscillations provide hydrocarbon source, reservoirs, and traps. This book from the SEG Course Notes series examines these traits, as they exist in the on- and offshore region of Louisiana.”