Bedrock fracture control of glacial erosion processes and rates
Bedrock fracture control of glacial erosion processes and rates
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DOI：
10.1130/g30576.1
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发表时间：
2010-05-01
期刊：
影响因子：
5.8
通讯作者：
Stock, Greg M.
中科院分区：
文献类型：
--
作者：
Duehnforth, Miriam;Anderson, Robert S.;Stock, Greg M.
岩石类型和构造历史对冰川侵蚀速率的重要性，以及冰川采石和磨损的相对作用，知之甚少。我们使用浓度的宇宙成因Be-10在冰川抛光和测量基岩断裂间距，探讨侵蚀率和岩石断裂之间的关系在23个站点沿着图奥勒米河谷和5个站点在Tenaya峡谷在约塞米蒂国家公园，加州，美国。大多数站点产生Be-10浓度，可以最好地解释为反映单独冰后期核素积累。然而，六个地点显示出令人不安的高浓度，这意味着在末次冰期期间，冰前核素库存的不完全清除;这些要求在末次冰期循环中的侵蚀是
The importance of rock type and tectonic history on rates of glacial erosion, and the relative roles of glacial quarrying and abrasion, are poorly understood. We use concentrations of cosmogenic Be-10 in glacial polish and measurements of bedrock fracture spacing to explore the relationship between erosion rates and rock fracturing at 23 sites along Tuolumne River valley and five sites in Tenaya Canyon in Yosemite National Park, California, USA. Most sites yield Be-10 concentrations that can be best explained as reflecting solely postglacial nuclide accumulation. Six sites, however, display anomalously high concentrations, implying incomplete removal of the pre-glacial nuclide inventory during the last glaciation; these require that erosion in the last glacial cycle was