Topographic stress control on bedrock landslide size
Topographic stress control on bedrock landslide size
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DOI：
10.1038/s41561-021-00739-8
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发表时间：
2021-04
影响因子：
18.3
通讯作者：
Gen K. Li;S. Moon
中科院分区：
文献类型：
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作者：
Gen K. Li;S. Moon
滑坡是一种主要的自然灾害，是山脉侵蚀、化学风化和有机碳转移的主要驱动力。评估滑坡对地球系统的影响需要了解其规模的控制，这是不太清楚。在这里，我们表明，地形应力，造成构造应力和地形之间的相互作用，影响基岩滑坡的规模在景观尺度上通过调制地下材料强度，通过断裂和风化。利用三维地形应力模型，我们描述了藏东山区结晶岩地形地下开放断裂带的空间格局。然后，我们将预测的开放性断裂带与982个绘制的基岩滑坡进行比较。结果表明，具有较深的地下开放断裂带的地区往往容纳较大的滑坡。这可能是由于地形诱导的裂缝对材料强度和地下水流路径和速率的影响。我们的结论是，山坡故障的程度取决于遥远的构造力和当地的地形，减灾，景观演变和全球碳循环的影响。
Landslides are a major natural hazard and act as a primary driver of erosion, chemical weathering and organic carbon transfer in mountain ranges. Evaluating the impact of landslides on Earth systems requires knowledge about the controls on their size, which are not well understood. Here we show that topographic stress, resulting from the interaction between tectonic stress and topography, influences bedrock landslide size at landscape scales by modulating the subsurface material strength through fracturing and weathering. Using a three-dimensional topographic stress model, we characterize the spatial pattern of subsurface open-fracture zones in a crystalline-rock terrain of the eastern Tibetan mountains. Then, we compare the predicted open-fracture zones with 982 mapped bedrock landslides. The results show that areas with deeper subsurface open-fracture zones tend to accommodate larger landslides. This is probably due to the influences of topographically induced fractures on the material strength and groundwater flow paths and rates. We conclude that the extent of hillslope failure depends on both distant tectonic forces and local topography, which has implications for hazard mitigation, landscape evolution and the global carbon cycle.