Tectonic control on 10Be‐derived erosion rates in the Garhwal Himalaya, India
Tectonic control on 10Be‐derived erosion rates in the Garhwal Himalaya, India
复制标题
印度 Garhwal 喜马拉雅山 10Beâ 侵蚀速率的构造控制
DOI：
10.1002/2013jf002955
复制
发表时间：
2014
期刊：
影响因子：
--
通讯作者：
Strecker
中科院分区：
文献类型：
--
作者：
Scherler;Bookhagen;Strecker
喜马拉雅山脉的侵蚀是地球上最大的质量再分配之一，并为气候和构造之间的反馈循环模型提供了燃料。尽管喜马拉雅山脉侵蚀的总体趋势是众所周知的，但控制侵蚀的因素的相对重要性却没有受到很好的限制。在这里，我们展示了印度北部加尔瓦尔喜马拉雅亚穆纳集水区2510Be得出的流域平均侵蚀率。尽管坡度均匀，但小喜马拉雅的支流侵蚀速率为~0.10.5 mm yr−1，高喜马拉雅的支流侵蚀速率为~1至2 mm yr−1。侵蚀速率数据与5公里半径起伏的集水区平均值、河道陡度指数和比水流功率相关，但存在不同程度的非线性。相似的非线性关系和决定系数表明，地形陡度是侵蚀空间变异性的主要控制因素，年径流量的两到三倍的差异在该地区并不重要。相反，研究区侵蚀的空间分布符合岩石抬升模式在很大程度上受喜马拉雅主逆冲断层(MHT)的缩短速率和几何形状控制的构造模式。正如地球物理数据所显示的，我们的数据支持MHT在小喜马拉雅之下的浅倾斜，随后在高喜马拉雅之下的中地壳斜坡。最后，对较大干流河流的采样结果分析表明，10Be的侵蚀速率具有显著的变异性，可能与不同支流的泥沙供应不成比例和干流河道混合不充分有关。
Erosion in the Himalaya is responsible for one of the greatest mass redistributions on Earth and has fueled models of feedback loops between climate and tectonics. Although the general trends of erosion across the Himalaya are reasonably well known, the relative importance of factors controlling erosion is less well constrained. Here we present 2510Be‐derived catchment‐averaged erosion rates from the Yamuna catchment in the Garhwal Himalaya, northern India. Tributary erosion rates range between ~0.1 and 0.5 mm yr−1in the Lesser Himalaya and ~1 and 2 mm yr−1in the High Himalaya, despite uniform hillslope angles. The erosion‐rate data correlate with catchment‐averaged values of 5 km radius relief, channel steepness indices, and specific stream power but to varying degrees of nonlinearity. Similar nonlinear relationships and coefficients of determination suggest that topographic steepness is the major control on the spatial variability of erosion and that twofold to threefold differences in annual runoff are of minor importance in this area. Instead, the spatial distribution of erosion in the study area is consistent with a tectonic model in which the rock uplift pattern is largely controlled by the shortening rate and the geometry of the Main Himalayan Thrust fault (MHT). Our data support a shallow dip of the MHT underneath the Lesser Himalaya, followed by a midcrustal ramp underneath the High Himalaya, as indicated by geophysical data. Finally, analysis of sample results from larger main stem rivers indicates significant variability of10Be‐derived erosion rates, possibly related to nonproportional sediment supply from different tributaries and incomplete mixing in main stem channels.
登录
查看更多内容
影响因子：
6.3
作者：
Hendrik Wulf;B. Bookhagen;D. Scherler
通讯作者：
Hendrik Wulf;B. Bookhagen;D. Scherler
造山的数值模拟：侵蚀规律与地壳流变学之间的相互作用
影响因子：
5.2
作者：
Vincent Godard;R. Cattin;J. Lavé
通讯作者：
J. Lavé
构造对印度普里奥-更新世喜马拉雅前陆盆地河流沉积物的影响
DOI：
--
发表时间：
2003
期刊：
影响因子：
--
作者：
Rohtash Kumar;Sumit Ghosh;R. Mazari;S. Sangode
通讯作者：
S. Sangode
影响因子：
4.2
作者：
J. Vannay;B. Grasemann;M. Rahn;W. Frank;A. Carter;Vincent Baudraz;M. Cosca
通讯作者：
J. Vannay;B. Grasemann;M. Rahn;W. Frank;A. Carter;Vincent Baudraz;M. Cosca
喜马拉雅西北地区季节性降水梯度及其对河流泥沙通量的影响
影响因子：
3.9
作者：
Bookhagen;Scherler
通讯作者：
Scherler