COLLABORATIVE RESEARCH: Chemical Fingerprinting of Ash Beds in the Terminal Proterozoic Nama Group, Namibia

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Collaborative research: Chemical Fingerprinting of Ash Beds in the Terminal Proterozoic Nama Group, NamibiaBeverly Saylor.0073700Warren Huff.0073834The terminal Proterozoic to Cambrian Nama Group of Namibia is one of the most comprehensive records of end Proterozoic events. The Schwarzrand Subgroup of the Nama Group contains 15 stratigraphically distinct volcanic ash beds, which are constrained by U-Pb geochronology to a time span of at most 6 m.y. These event beds have tremendous chronostratigraphic value as high-resolution, widespread, time-parallel layers. This feasibility study will evaluate the potential for using geochemical fingerprinting techniques to uniquely identify and correlate ash beds in the Schwarzrand Suybgroup. Correlations of some widespread ash beds are already well established based on the physical stratigraphy. Whole rock and fluid inclusion studies of samples from these beds will control for within bed variability of chemical signature. Three widely separated, complete sections of the Schwarzrand Subgroup preserve nearly all the ash beds in replicate. Comprehensive analyses of ash bed samples from these sections ill compare between bed vs. within bed compositional differences and will test the resolution of the fingerprinting method.