PERI-GONDWANAN DERIVED SEDIMENT IN THE ARKOMA BASIN FROM THE NORTH OR SOUTH?: THE DETRITAL ZIRCON RECORD OF A UNIQUELY CONCENTRATED NON-LAURENTIAN SOURCE SIGNAL IN THE LATE PALEOZOIC

Late Paleozoic sediment transport within and across Laurentia informs us on the processes affecting the Earth’s surface (e.g., tectonics, climate) during the most recent episode of super-continent assembly. Peri-Gondwanan terranes that collided with the eastern and southern margins of Laurentia host unique detrital zircon ages relative to the adjacent continent. However, due to their similar geologic histories, detrital zircon U-Pb dates alone make it difficult to discriminate between peri-Gondwanan terranes. Along southeastern Laurentia, in the Arkoma Basin (modern-day Arkansas-eastern Oklahoma, U.S.A.), we identify a brief episode in the Middle Pennsylvanian when a relatively concentrated peri-Gondwanan detrital zircon signal appears in the stratigraphic record. The Sabine terrane to the south of the basin is the most likely source given its proximity. However, contextual data such as predominantly north-to-south paleocurrents and proximal to distal facies relationships support a northern source (e.g., Ganderia-Avalonia-Megumia terranes). In further support of a northern source, while the arrival of the peri-Gondwanan detrital zircon signal in the Arkoma Basin and on the Cherokee shelf appears to have been coeval, this signal persisted on the shelf, which is north of the basin, after it had been diminished in the basin. To evaluate northern versus southern peri-Gondwanan detrital sources in the Arkoma Basin, we use other provenance identification tools such as bottom-up source modeling, source mapping, and sandstone petrography to characterize the nature and distribution provenance in and around the basin. Furthermore, we explore the implications of northern versus southern sourcing scenarios on late Paleozoic tectonics and continental-scale drainage dynamics.