SEDIMENT PROVENANCE USING COUPLED U/PB DETRITAL ZIRCON AND 40AR/39AR DETRITAL MUSCOVITE ANALYSIS, CARBONIFEROUS OUACHITA-ARKOMA BASIN, SOUTHEASTERN OKLAHOMA

The Ouachita and Arkoma Basins record the transition from a passive to tectonically active margin during the mid-Carboniferous. Gondwanan arc terranes (microcontinents) docked onto the Laurentian margin, a result of a relatively “soft collision”. The Ouachita Basin, a remnant ocean basin, experienced slow sedimentation throughout much of the Paleozoic. The Arkoma Basin, a peripheral foreland basin filled with syntectonic sediments exceeding ~6 km thickness. The relatively sediment starved basin underwent rapid deposition during the Mid-Carboniferous as a direct result of closing the Ouachita Basin, collision of Laurentia and Gondwana, and concurrent eustatic sea level regression. Increased tectonic load from the suturing between Laurentia and Gondwana tilted the North American Craton exposing cratonic rocks that subsequently altered depositional patterns, provenance, and drainage pathways. The present study uses detrital minerals from Late Miss. to Middle Penn. strata of the Arkoma-Ouachita Basins to investigate the impacts that the Ouachita orogenesis and the Mid-Carboniferous Eustatic Event had on sediment dispersal as the basin evolved. Detrital zircon U/Pb ages from 6 Carboniferous samples (n>480 total), 4 from uppermost Miss. Stanley Group and 2 from lowermost Penn. Jackfork Group, along with 14 Carboniferous 40Ar/39Ar detrital muscovite samples from Late Miss. Stanley Group to Middle Penn. Krebs Group (n>1400 total). Detrital zircon ages from the Miss. Stanley Group show a significant amount of ages from 500-700 Ma with an equally prominent Mesoproterozoic mode, while zircon ages from the Penn. Jackfork Group display a dominant Mesoproterozoic mode with subordinate Taconic and Acadian modes. The detrital muscovite ages give a consistent Taconic mode (ca. 455 Ma) throughout most samples along with two lesser Acadian modes ca. 370-375 Ma and 400-405 Ma. Resembling the zircon record, the Miss. Stanley Group muscovite also has a considerable amount of Peri-Gondwanan grains older than 460 Ma. The detrital ages of the Miss. Stanley Group suggest that there were multiple sources of detritus into the basin from both Laurentian and Gondwanan crusts. The dominant Taconic and Acadian modes seen throughout the Penn. imply an interior longitudinal system sourcing sediment into the Ouachita-Arkoma Basins.