Rock hammer shows meter-scale width of a felsic sill
Rock hammer shows meter-scale width of a felsic sill associated with zinnwaldite-bearing Sn-granite at the Groundhog Basin Ag-Sn-Pb-Zn deposit. The layered host rocks to the sill are garnet-quartz-biotite gneiss. Field work at Northeast flank of Groundhog Basin in the Stikine River corridor on the Transboundary Waters Project. The purpose of this work is to understand the geochemistry, mineralization, and distribution of the rocks that contribute to the chemistry of streams in the Stikine River corridor.
Sue Karl, U.S. Geological