Post-Hunton Unconformity and Its Effect on Pre-Mississippian Distribution in Southern Oklahoma: ABSTRACT

Abstract

The post-Hunton unconformity in southern Oklahoma is evidenced by the age of the rocks encountered at the base of the Woodford shale. A pre-Pennsylvanian paleogeologic map, showing surface distribution, accompanied by a pre-Woodford distribution map, illustrates the extent of post-Hunton folding and suggests a tectonic framework for dividing southern Oklahoma into six geologic provinces. thickness contours define areas of pre-Woodford structural movement. It is suggested that the first pronounced structure building and truncation of beds occurred during middle time at the close of the Silurian period. The exhibits radical variations in End_Page 213------------------------------ thickness as a result of the post-Hunton unconformity, and Woodford rests unconformably on rocks varying from Arbuckle in the Hollis basin in southwest Oklahoma to Upper in south-central Oklahoma. A unique carbonate sequence with maximum thickness of 125 feet in the subsurface occurs at the base of the Woodford shale, and rests unconformably on beds as old as Viola along the Mansville-Aylesworth trend in Marshall County, Oklahoma. This carbonate is an oil reservoir on the north flank of the Aylesworth anticline, and has been informally called Misener and Hunton detritum in the Ardmore area. This carbonate occurrence, its lithologic description, and its possible relationship with the outcrop are briefly discussed. End_of_Article - Last_Page 214------------