RUI: Upper Devonian Black Shales in Eastern North America, Conodont Biostratigraphy, Frasnian-Famennian Mass Extinction Horizon, and Absolute Dates from Associated Ash Layers

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9614314 Over The Upper Devonian black shales in eastern North America are important for hydrocarbon resources, understanding of global climate change, and the occurrence of a global mass extinction event, have never been systematically collected to determine the complete conodont biozoneation. this is simply because workers have had difficulties recovering conodonts from the black shales and have instead focused on green shale and carbonate interbeds. The result is undescribed taxa, incomplete zonations, and tenuous correlations of black shales in the Appalachian, Illinois, and Michigan basins. High resolution biostratigraphy and recognition of global event horizons is possible by careful sampling of black shale horizons. Biozones, cryptic disconformities, the Frasnian-Famennian boundary, and the Devonian-Carboniferous boundary have been recognized in the Woodford Shale of Oklahoma - entirely within black shale. Similar sampling and processing techniques in the northern Appalachian Basin have recovered new taxa, as well as isolated the Frasnian-Famennian boundary in the Hanover Shale of New York and the Upper Olentangy Shale of Ohio. Conodonts have been described from the Middlesex and Pipe Creek shales, two petroliferous black shales that had previously been unzoned. The purpose of this project is to expand upon previous studies and preliminary sample materials that are currently under investigation to systematically collect black shale sequences in the three eastern North American basins, describe conodont faunas, and utilize revised taxonomy and correlation techniques to prepare complete zonal schemes for the Antrim Shale (Michigan Basin), Chattanooga Shale (southern Appalachian Basin), and New Albany Shale (Illinois Basin). This study will differ from previous works by collecting the black shale horizons. This will enable recognition of minor disconformities, ash horizons, and determine the ranges of biozones. Within this biostratigraphic framework small scale depositional cyc les will be correlatable between basins and absolute dates of known ash beds (e.g., Center Hill, Belpre), as well as ash beds found during recent sampling, will be tied together. The result will be a clearer understanding of biozone and depositional cycle intervals, and an indication of depositional rates for the different members of the eastern shale formations on relative and absolute time scales. This will also allow precise correlation of discrete members and beds within the black shale facies. Undergraduate research participation is a primary focus within the project. Students will collect, process, and analyze strata for microfossils and characterize ash horizons utilizing petrographic techniques, the scanning electron microscope, and energy dispersive x-ray analysis for elemental determination.