Middle Pennsylvanian (Desmoinesian) shelf to slope transition in the western Anadarko basin: stratigraphic relationships and origin of the Cherokee “Hot” Shale

Speaker: Jim Puckette

Location: Petroleum Alliance of Oklahoma

500 NE 4th St #200, Oklahoma City, OK 73104

Date: Wednesday, April 8th, 2026

Time: 11:30 am - 1:00 pm
Cost: $25 Members; $35 Non-members (lunch included)*

*Note the OCGS is unable to issue registration refunds as the luncheon catering is prepaid

Abstract:  

The Middle Pennsylvanian (Desmoinesian) Cherokee and Marmaton groups in the western Anadarko basin contain well defined shelf to slope transitions that are characterized by changes in interval thicknesses, depositional settings and facies. Except for the narrow fringe of orogenic deposits sourced from the Amarillo-Wichita Uplift, evolving Anadarko basin depocenters filled primarily with fine-grained sediments sourced from the northern Appalachian Mountains. During the Desmoinesian, cyclic eustatic changes in sea level driven largely by Milankovitch cycle induced waxing and waning of Gondwanan ice sheets resulted in mudrock dominated sequences on the slope that contain lesser amounts of thin carbonates, radiogenic organic-rich shales, and marine sandstones. Coeval sediments on the shelf were dominated by deltaic and coastal plain muds and marginal marine and valley-filling sands with abundant tidal features that indicate channel filling likely occurred during transgression that followed sea level decline and incision. Rapid transgressions of the low-declivity shelf facilitated widespread deposition of the thin radiogenic organic-rich shales, providing chronostratigraphic markers to subdivide the Cherokee and Marmaton groups. By Marmaton time, deposition on the broad northern Anadarko shelf included extensive carbonate units, including some separated by transgressive radiogenic shales formed during maximum flooding. On the shelf, the Little Osage and Excello radiogenic shales can be separated by tens of feet of Ft. Scott/Oswego Limestone. On the slope where water depth and/or turbidity prevented carbonate formation, the Ft. Scott Limestone is absent and the Little Osage Shale occurs on or within a few feet of the Excello Shale, increasing the total thickness of radiogenic and organic-rich shale in the “Cherokee Shale” interval and forming the Cherokee Hot Shale marker.

Speaker Biographical Sketch: 

Jim Puckette is Professor Emeritus in the Boone Pickens School of Geology at Oklahoma State University (OSU). Jim specializes in physical stratigraphy, sedimentology and petroleum geology. Prior to joining the faculty in 2000, he was an exploration geologist working for small independent companies that operated mostly in the northern and central Oklahoma. A native of eastern Oklahoma, Jim has championed studies related to Oklahoma’s water and oil and gas resources. He is presently involved in studies of conventional and unconventional oil and gas reservoirs including the Hunton Group and Pennsylvanian sandstones and carbonates. His interest in water resources resulted in participation in studies of the Arbuckle, Simpson, and Boone bedrock aquifers and alluvial and terrace aquifers along the Arkansas River. He has mentored 75 M.S. and 2 Ph.D. graduates. Jim is active in outreach through in-service teacher training and programs to school and youth groups. Jim thrives field work and was the Director of the OSU Les Huston Geology Field Camp near Cañon City, Colorado for more than 25 years.