The wide variability in structural styles within the growth-faulted, geopressured trends of the Texas Gulf Coast is illustrated by detailed structural maps of selected areas of the Wilcox and Frio growth-fault trends and quantified by statistical analysis of fault compartment geometries.

Deep-water sandstones of the Oligocene-age Hackberry unit of the Frio Formation contain significant quantities of oil and gas and remain potentially one of the most productive exploration targets in southeast Texas.

Gas reservoirs that water out under moderate to strong water drives are normally abandoned when the expenses associated with salt-water disposal make continued operations uneconomical.