Integrated examination of petrology, diagenesis, and depositional environment of the Catahoula Formation in Jasper County, Texas

Although extensive work addressing petrology, diagenesis and depositional environment of the Catahoula Formation in south and central Texas has been completed, limited information is present for units of east Texas, specifically Jasper County, Texas. Through field investigation, optical microscopy of thin sections, XRPD of clay sized fraction, and SEM, this study examines the petrology, diagenetic history, and depositional environment of the Catahoula Formation in Jasper County, Texas. Sandstone units are dominantly mature medium-fine grained sub-litharenites consisting of approximately 85% quartz, 4% feldspar, and 11% rock fragments (mean %). Quartz types are monocrystalline, 95%; and polycrystalline, 5%. Monocrystalline quartz types consist of undulose extinction, 36%; straight extinction, 39%; rutilated quartz, 17%; and coarse-medium silt sized quartz, 8%. Feldspars are 97% alkali and 3% plagioclase. Rock fragments are 88% sedimentary (SRF) and 12% volcanic (VRF). SRF consist of 66% chert and 34% lithic grains. VRF are vitric air-fall tephra. Devitrification of volcanic tephra and dissolution of feldspars are the primary sources of authigenic montmorillonite, kaolinite, and opal-CT cements. Units were never buried to significant depth based on absence of illite, quartz overgrowths, and solution contacts. Depositional facies are crevasse splay, floodplain, lacustrine, and fluvial channel.