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Isolation And Characterization Of Thermophilic, Calcium-Precipitating Bacteria Form Calcite Deposits At Yucca Mountain, Terry Ann Else, Curtis R. Pantle, Penny S. Amy, Mark P. Buttner, Amy J. Smiecinski

Publications (YM)

Calcite deposits, composed of a mixture of calcium carbonate and silicon dioxide, were found in fractures and small cavities within the welded tuff of Yucca Mountain. This research investigation involves determining the presence of thermophilic, calciumprecipitating bacteria within these deposits. The possible existence of thermophilic bacteria may help to resolve the issue of whether these calcite deposits formed from precipitation of dissolved calcium carbonate in rain water transported from the overlying soil environment or as a result of upwelling of geothermally-heated waters transported from below the mountain. Evidence for microbially-influenced calcite precipitation in these deposits is indicated by the presence …