Quantitative Characterization of Early Pennsylvanian Laurentian Fluvial Systems and Detrital-Zircon U-Pb and ɛHf Provenance Studies of the Deepwater Ouachita basin
The Paleozoic Appalachian orogeny resulted in large-scale reorganization of North American river systems and sediment routing. Several detrital zircon studies document the arrival of Appalachian-derived age populations beginning in the Carboniferous in western North America, including in the Grand Canyon, the Ancestral Rocky Mountains in Colorado, and the Bighorn basin of Wyoming, and inferred large-scale east-to-west sediment transfer (Gehrels et al., 2011; May et al., 2013; Nair et al., 2018). However, there are numerous topographic obstacles to an east-to-west flowing fluvial system, including several north-south trending paleovalleys associated with the Illinois and Appalachian basins, and the Ouachita deepwater sink. Quantitative characterization of these paleovalleys from source terrains to deepwater deposits will test this continental-scale fluvial system hypothesis and refine the character of late Paleozoic North American sediment routing. I propose a detrital zircon U-Pb and ɛHf provenance study of the Early Pennsylvanian (Morrowan) Jackfork Group and Johns Valley Shale of the deepwater Ouachita basin and a sedimentological study of potential feeder fluvial systems to examine potential sediment routing corridors. This study will determine whether sediment that comprises the Jackfork Group and Johns Valley Shale was from the northern (craton), eastern (Appalachian orogen), or southern (including exotic magmatic arc) parts of Laurentia, or some combination of these source areas. The delineation of these potential north-to-south feeder fluvial systems will constrain large-scale east-to-west sediment transfer on late Paleozoic Laurentia.
AAPG Datapages/Search and Discovery Article #90351 © 2019 AAPG Foundation 2019 Grants-in-Aid Projects