HYDROTHERMAL INFLUENCE, DEBRIS-FLOW HAZARDS, AND GLACIAL PROCESSES IN MOUNT RAINIER NATIONAL PARK, WA

Mount Rainier is an active stratovolcano, capped by a radial network of over twenty glaciers. Glacial erosion and hydrothermal alteration weaken rock, producing thick drapes of sediment on some glaciers. Rivers of meltwater emanating from these glaciers supply water, sediment, energy and nutrients to cities, farms, and ecosystems in the surrounding lowlands. This presentation will share hydrochemical analysis of glacial meltwater from Mount Rainier, revealing wide spatial and temporal variation in sediment transport and chemical composition. Some of the spatial variation may be explained by the degree to which subglacial environments are influenced by the mountain's extensive hydrothermal system; temporal variation can be attributed primarily to atmospheric influences on the glacial environment. This presentation will also share observations of and new efforts to monitor debris flow activity from South Tahoma Glacier in the southwestern quadrant of the park.