Petrology of Bethel Sandstone of South-central Illinois

abundant aggregates altered analysis angular apatite appears arenaceous Assoc Asst bedding Bethel formation Bethel sand Bethel sandstone calcite Canadian shield carbonate cement cent chert chlorite clastic cleavage coarse coarser colorless cordierite County crystal cycle of erosion degree of rounding deposition derived detrital grains detritus diameter earlier cycles euhedral evidence feldspar finer flakes fossil fracturing furnished Geol Geological Geologist glauconite grains show green greenish heavy minerals hematite Illinois basin ilmenite indicate interstitial irregular Jour land mass leucoxene limestone Llanoria mafic mafic minerals magnetite material metamorphic numerous occurs opaque ordinarily original grain oxidation Ozarkia Paint Creek pegmatitic period of erosion Peter sandstone Petrology PH.D phi units plagioclase planes pore porosity quartz enlargement quartz grains rare replacement Research Assistant rocks rutile samples sand grains secondary enlargement secondary quartz secondary silica sediments sericite shale shale fragments shape silica solution thin tion tourmaline varieties zircon zone