Inferences for yucca mountain unsaturated-zone hydrology from secondary minerals

摘要

Secondary calcite and opal deposits contain information on past unsaturated-zone percolation flux within Yucca Mountain. Physical,geochronological and isotope data are used to interpret the history and physical processes of fracture flow at the potential radioactive waste repository site.Results suggest that some of the vertical fracture flux in the unsaturated zone may be diverted laterally within non-welded tuff units to zones of structural displacement where vertical percolation may resume.Temporal variations in deep percolation flux also may be dampened by the site hydrogeology in spite of variable infiltration caused by past changes inclimate.