Shallow salt diapirs in the East Texas sedimentary basin are currently being considered as repositories of high-level nuclear waste (Kreitler, 1980; Kreitler and others, 1980; Kreitler and others, 1981). A crucial aspect of such an assessment involves understanding how fresh meteoric groundwater may impact long-term dome stability through dissolution. In the East Texas Basin, the zone of fresh meteoric groundwater includes the Wilcox Group, which encases or surrounds the upper 100 to 500 m (330 to 1640 ft) of most shallow diapirs.
The distribution of Wilcox depositional facies may strongly influence flow directions and velocities of groundwater around salt domes. The Wilcox Formation exhibits extreme heterogeneity due to lateral and vertical variations in the distribution of highly permeable sands and other sandstones, mudstones, and lignites with low permeabilities. Variables affecting aquifer characteristics include thickness and hydraulic conductivity, which vary partly as a function of depositional facies and sand-body geometry, including sand body thickness, permeability, and interconnectedness.
This report provides the basic facies and sand body data for computer modeling of groundwater flow around Oakwood Dome (Fogg, 1980a). Two main problems are addressed in this study: (1) determining the facies distribution and sand-body geometry of sandstones with high hydraulic conductivities and the greatest potential for possible dome dissolution, and (2) understanding how facies distribution is affected by syndepositional dome growth.Bureau of Economic Geolog
