Chemical weathering in the temperate glacial environment of the Northern Cascade Mountains

摘要: Chemical weathering activity in the South Cascade Glacier area of Northern Cascades is both intensive and extensive. The presence chemical shown by (1) pedogenic clay assemblages which vary according to bedrock mineralogy, (2) distinctive water types co-exist with discrete (3) striking transformation as it runs over bedrock. mechanisms are primarily carbonation oxidation. Even though zoned soils rare or absent, minerals such vermiculite, smectite, gibbsite lepidocrocite accumulate locally. Cationic denudation watershed (930 mE/m2yr) substantially higher than world average (390 mE/m2yr), indicating intensity an environment. Evidently low temperatures generally associated active glacier do not inhibit reactions. On contrary, turbulent well-aerated flows prevalent environment promote constantly replenishing acid potential water. Also, mechanical effects glaciation apparently expedite process continuously reviving fresh surface rock exposed A crucial limiting factor seems be supply hydrogen ion from atmosphere. By virtue fact that temperate glacial represents extreme hydrologic activity, may, therefore, represent even absence normal biologic processes soil.