Abstract: Ancient Delta Systems in Gulf Coast Area
The interpretation of ancient sedimentary environments of deposition best is done by using petrographic criteria coupled with the study of sedimentary structures and three-dimensional geometry. However, in subsurface studies data other than three-dimensional geometry seldom are available.
The recognition of subsurface deltas and associated environments, which have proved to be the most important reservoirs for hydrocarbons in the Gulf Coast and elsewhere, depends on the use of gross-interval isopach and net-sand maps, and the use of the spontaneous-potential log profile as an indicator of vertical trends in grain size. Examples from the Wilcox (Eocene) of southwest Texas, the upper Miocene of southeast Louisiana, and the Mississippian of the Black Warrior basin (Mississippi and Alabama) illustrate the technique.
AAPG Search and Discovery Article #90975©1976 GCAGS- GC Section SEPM Annual Meeting Shreveport, Louisiana