ABSTRACT: Geochemical denudation rates and solute transport mechanisms in a maritime temperate glacier basin

CGRG Bibliography of Canadian Geomorphology
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Abstract

Cation and silica transport in supraglacial, subglacial, and valleyside waters from a temperate glacier fluvial system in British Columbia is reported. Dissolved cation loss from the basin of Berendon Glacier is calculated at 947 mequiv/sq meter/yr, with calcium accounting for nearly all of this loss. The geochemical denudation rate is substantially greater than the world average of 390 equiv/sq m/yr, but agrees with similar studies from the Cascade Range in the U.S. Abundant precipitation is probably responsible for the significant geochemical denudation, despite reduced chemical activity at low annual temperatures. When absorption is considered in the removal process, the major cation denudation rate increases by about 10% and doubles the loss of certain cations such as sodium. Debris-water contact time appears to exert a significant control on the cation and silica concentrations exhibited by the various water types moving through the basin. Firn, glacier ice, and supraglacial streams generally possess the lowest ionic concentrations, and subglacial streams, valleyside streams, and ponds generally contain the highest. Anthropogenic chemical input to the Berendon basin is measurable and consists of trace metal rich dust originating at a mining and milling operation close to the glacier terminus. Aeolian transport is responsible for distributing Cu, Cr, Ni, and Pb throughout the watershed

Bibliography of Canadian Geomorphology