Strontium 87/strontium 86 as a tracer of mineral weathering reactions and calcium sources in an Alpine/Subalpine Watershed, Loch Vale, Colorado

摘要: Sr isotopic ratios of atmospheric deposition, surface and subsurface water, geologic materials were measured in an alpine/subalpine watershed to characterize weathering reactions identify sources dissolved Ca stream water. Previous studies have noted excess water above that expected from stoichiometric the dominant bedrock minerals. Mixing calculations based on 87 Sr/ 86 indicate annual basis, 26 67% export streams is atmospherically derived, 23 61% plagioclase, remainder calcite present trace amounts bedrock. A potential source error when applying isotopes catchment determination released by mineral weathering, which complicated wide range compositions, particularly older rocks, variable rates at minerals weather. In this study, base-flow chemistry was used represent derived because it effectively integrates potentially composition alpine environment.