Mobile Basin-Shelf Border in Northeast Oklahoma During Desmoinesian Cyclic Sedimentation: ABSTRACT

Abstract

Desmoinesian coal cycles and marine limestone bank episodes in northeastern Oklahoma are related to the mobility of the basin-shelf border area. This mobility may reflect the northward passage of a long-term crustal wave generated either by the Carboniferous convergence of the North American and African plates and/or the intense activity along the orogenic arcs comprising the now buried Llanoria complex in the northern Gulf of Mexico area. The shelf-edge carbonate banks (Wapanucka Limestone), located along the Choctaw fault in Early Pennsylvanian time, had moved 80 mi (128 km) north to Tulsa County by Middle Pennsylvanian (Marmaton) time and then another 80 mi (128 km) north to southern Kansas by Late Pennsylvanian time. Other tectonic and corresponding stratigraphic elem nts also show a broad northward shift. These include an isostatic compensated couplet between basinal foredeep and orogenic arc (zeugogeosyncline of Kay), a usually subsiding paleobathymetric axis and the southward-tilting slope and shelf of the craton border area. Complicating this simple picture is the overprint of eustatic rise and fall of sea level perhaps caused by waxing and waning of Gondwana glaciers that persisted throughout much of the Late Carboniferous. Rising sea level on the northern shelf was marked by coals and limestones giving way to gray to black organic clay shales; and later, stagnant to lowering sea level was marked by progradational delta and associated silty to sandy deposits and finally a deep soil profile. Together these constitute typical cyclothems which are numerous throughout the shelf areas in northeast Oklahoma and adjoining states. These include some of the more productive Oklahoma oil and gas sandstones such as the Cleveland, Skinner, Red Fork, Bartlesville, and Booch. The thicker basinal deposits of the southern Arkoma basin also contain some coals, but sandstones rather than shale or limestone commonly overlie such coals, perhaps owing to the greater ruggedness and tectonism of its source area in the east and south. End_of_Article - Last_Page 2115------------