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STRUCTURAL GEOLOGY OF NORTH AMERICA 



Ardmore Basin. The Ardmore basin is a folded and faulted basin 

 between the Arbuckle anticline (Mountains) and Criner Hills. It con- 

 tains a thick and deeply depressed Pennsylvanian sequence of clastic 

 sediments, overlying a rather thick Cambro-Ordovician carbonate se- 

 quence with unconformable relations attesting two principal times of 

 orogeny. These will be outlined presently. 



Over 30,000 feet of Paleozoic sediments are involved, about 13,000 feet 

 of which are Pennsylvanian and include the Springer, Dornick Hills, 

 Deese, Hoxbar, and Pontotoc formations, from oldest to youngest. Most 

 of the pre-Pennsylvanian beds are limestone, and the Pennsylvanian are 

 mostly sandstone and shale. The Ardmore basin is considered a foredeep 

 by van der Gracht, north of the Wichita and Criner Hills anticlinorium. 

 At the time of deposition of the beds, the basin spread over the site of 

 the present Arbuckle Mountains as well as the present Ardmore syncline, 

 and extended to the Hunton-Tishomingo landmass (Dott, 1934). 



Anadarko Basin. North of the Wichitas is the extensive Anadarko 

 basin. It occupies the greater part of western Oklahoma. Its axis runs 

 west-northwest and approximately parallels the Wichita-Amarillo up- 

 lift. The Permian beds thicken to 4500 feet just 25 miles north of the near- 

 est granite outcrop. The thickness of the Pennsylvanian in the center of the 

 basin is unknown but may be rather great, notably in the eastern part, 

 and may be an extension of the Ardmore basin. Becker (1930) cal- 

 culates the highest part of the Wichita anticlorinium to have been 

 elevated structurally about 19,000 feet above the axis of the Anadarko 

 "foredeep." 



The Ardmore trough trends into the Anadarko basin under the blanket 

 of Permian red-beds and Cretaceous. It is not known how much Pennsyl- 

 vanian subsidence occurred in the Anadarko basin, but it is clear that 

 most of the subsidence in the Ardmore basin is Pennsylvanian, and at 

 least 4500 feet of subsidence in the Anadarko is Permian. 



Paleogeology of the Wichita-Ouachita Region 



The history of sedimentation in Oklahoma is in two distinct divisions, 

 both in time and space. An uplift and peninsula through Texas from 

 Mid-Ordovician to Mid-Mississippian separated the West Texas basin 



Fig. 15.7. Mid-Ordovician to Early Mississippian tectonic features of Texas and adjacent areas. 

 After Adams, 1954. 



from the Oklahoma basin. See Fig. 15.7. The Cambro-Ordovician 

 Arbuckle limestone sea spread across the arch in platform fashion where 

 about 1000 feet of carbonates accumulated, but in the Oklahoma basin 

 on the northeast 4000 to 6000 feet accumulated. On top of these 

 deposits, while the Texas arch was emergent, an additional 3000 feet of 

 sediments were deposited in Late Ordovician, Silurian, and Early 

 Devonian time. These were also mostly carbonates. To the north in 

 Kansas the equivalent strata are only about 1000 feet thick. The region 



