HETEROGENITY OF CLASTIC PROVENANCE TO THE PENNSYLVANIAN ANADARKO BASIN AND IMPLICATIONS FOR PALEOGEOMORPHOLOGY

The Anadarko Basin of western Oklahoma hosts a 12 km section of Paleozoic sedimentary rocks, recording Early Paleozoic rift subsidence and Late Paleozoic convergence. Pennsylvanian inversion of the Southern Oklahoma Aulacogen formed the Wichita Mountains uplift and corresponding Anadarko basin, which preserves 7.5 km of Pennsylvanian-Permian section, including the “Granite Wash” deposited in the deep Anadarko, and coeval sands that accumulated in shelfal regions. Here we integrate framework mineralogy and U/Pb detrital zircon geochronology to reconstruct Middle-Late Pennsylvanian drainage pathways into the Anadarko Basin. Preliminary framework mineralogy indicates three provenance populations: quartzose eastern shelf sands, quartzolithic western shelf sands and feldspathic-lithic deep basin sands—the latter with diagnostic Wichita Granite textures. Detrital zircon data similarly indicate three distinct provenance spectra within the shelf and deep basin sandstones. The Desmoinesian Granite Wash sands contain a predominate Wichita Igneous Suite peak. The Desmoinesian eastern shelf sands exhibit Peri-Gondwanan, Appalachian and Grenville peaks, but in distinctly differing populations. The deep Anadarko Virgilian sands contain a primary Grenville peak, with secondary Granite-Rhyolite, Yavapai-Matzatzal and Appalachian peaks. Although proximal to the Anadarko foredeep, the deep Anadarko Virgilian sands contain only three zircon grains with Wichita igneous suite ages. These results indicate that the Wichita Mountain Igneous suite forms a relatively subordinate proportion of clastic influx into the Anadarko basin. Additionally, the heterogeneity of the Desmoinesian sands suggests the influence of multiple, partitioned drainage networks that likely reflect complex regional paleogeography and reactivated basement structures. Sediment recycling explains some pre-Devonian zircon populations, but the Appalachian peak indicates some long-distance transport from the east-southeast during the Pennsylvanian. Future research will explore provenance trends on the western shelf, and compile detrital zircon data from adjacent basins to refine paleodrainage pathways.