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Detrital zircon geochronology and provenance analysis of the Desmoinesian (Middle Pennsylvanian) Bartlesville and Red Fork sandstones, Cherokee Platform and Anadarko Basin, Oklahoma

Tunin, Zachery T.
The Middle Pennsylvanian was a critical time in the evolution of the North American Craton. Tectonic events caused major changes in paleogeography, resulting in the emergence of new sediment sources that changed sediment dispersal patterns and initiated new and complex variations in detrital compositions of sediments. During the early Desmoinesian, the principal change in the Midcontinent Region was the introduction of lithics and, more specifically, metamorphics of unknown provenance to the northeast-southwest trending fluvial, deltaic sediment dispersal systems. This permitted the development of rock compositions and fabrics favorable for dissolution and reservoir genesis. These sandstones became the prolific oil- and gas-producing reservoirs of the Cherokee Group. This study reports 867 new concordant detrital zircon U-Pb ages and 120 new EHf(t) values from three early Desmoinesian, lower Cherokee, sandstone samples to determine sediment provenance. These samples include cuttings from the Red Fork Sandstone in the Anadarko basin and outcrops of the Taft Sandstone and Bartlesville Sandstone in northeastern Oklahoma.
Zircons in the analyzed sandstones are characterized by two major signatures: Type 1 and Type 2. Type 1 quartzarenites (Taft Sandstone) have a significant age cluster corresponding to the Yavapai-Mazatzal (1600-1800 Ma) province. In contrast, Type 2 sublith- to litharenites (Bartlesville and Red Fork sandstones) have major age clusters corresponding to the Appalachian Synorogenies (350-490 Ma) and the peri-Gondwanan (Neoproterozoic) terranes (530-760 Ma). Comparative analysis of published detrital zircon ages and EHf(t) signatures from Pennsylvanian aged sandstones and early Paleozoic strata and basement rocks across the North American Craton suggests the lower Cherokee sandstones reflect both local sourcing within the Midcontinent and sourcing by distal, extrabasinal, fluvial systems. Detrital zircon signatures from the Type 2 sandstones support the exhumation of exposed peri-Gondwanan basement material and the recycling of Cambrian-Ordovician sedimentary cover in the northern Appalachian region as the primary source of lithics (including metamorphic fragments) that emerged in early Desmoinesian sandstones on the Midcontinent. Signatures from Type 1, Taft, Sandstone indicate that quartz-rich detritus along the western flank of the Ozark Uplift was likely sourced from recycled late Mississippian strata and granitic basement exposed on the Ozark Uplift. Together, these compiled data support the extension of a NE-SW transcontinental sediment dispersal system with headwaters in present-day southeast New England to the southern Midcontinent in the Middle Pennsylvanian. This system was primarily sourced and influenced by the Alleghenian orogeny on the eastern Laurentian margin. Periodic filling of intracratonic basins also partially influenced the dispersal system. Local variation in detrital composition, including the absence of lithics in the Taft Sandstone, is attributed to local drainage networks that collected sediment from unroofed paleohighs.