Application of Detrital Zircon Geochronology to Determine the Sedimentary Provenance of the Middle Bloyd Sandstone, Arkoma Shelf, Northern Arkansas

The sedimentary provenance of the middle Bloyd sandstone and subsequent sediment transport and dispersal patterns of the Early Pennsylvanian were interpreted by utilizing U-Pb detrital zircon geochronology. Eight middle Bloyd sandstone samples were analyzed. A total of 855 concordant analyses resulted. Peaks occurred at 350-500 Ma, 950-1200 Ma, 1300-1500 Ma, 1800-2300 Ma, and \u3e2500 Ma. These peaks were determined to represent crystalline source rocks on the Laurentian craton from Acadian-Taconic, Grenville, Midcontinent Granite-Rhyolite, Yavapai-Mazatzal, Paleoproterozoic, and Archean Superior Provinces respectively. Grenville age zircons were the most common zircons identified in the middle Bloyd sandstone samples. The Appalachian Mountain region is determined to be the primary source of sediment in the middle Bloyd sandstone as evidenced by the high percentage of grains attributed to the Acadian-Taconic and Grenville age terranes. The moderate presence of Midcontinent Granite-Rhyolite and Yavapai-Mazatzal age zircons in the middle Bloyd sandstone indicates that a secondary source of sediment for the sandstone unit likely originated from north and west of the study area. Sediments were likely transported from both north-northwestern and eastern source regions into a common drainage basin that allowed movement of sediments southward by a substantial fluvial system onto the Arkoma Shelf in northern Arkansas where the deposition of the middle Bloyd sandstone occurred as part of a large scale braided stream system near the Pennsylvanian-Morrowan coast