Abstract

A lithofacies analysis of the subsurface Atoka clastic rocks in parts of Jack, Palo Pinto, Parker and Wise Counties, north-central Texas, was designed to provide meaningful interpretation of depositional environments that existed during Atoka time as well as the most favorable locations for production of hydrocarbons.

The Atoka clastic rocks are the product of the Ouachita orogen interacting with an epeiric sea on the west during Early Pennsylvanian time. They are a series of sediments deposited between the Caddo limestone of Strawn age and the top of Marble Falls Formation of Morrowan age. The study area is in the west-central part of the Fort Worth Basin which is a pericratonic or retroarc basin in plate tectonic terms with its deepest part being adjacent to the folded and thrust-faulted Ouachita belt on the southeast.

The subsidence of the Fort Worth Basin during Atoka time accomodated the eroded detritus from the southeastern rising Ouachita system. Limestones were accumulating in the western area where more stable conditions existed on the Concho Platform.

The investigation provided valuable information that may augment hydrocarbon exploration programs throughout the basin; the procedure of investigation can be applied to similar basins beyond the confines of the immediate area.