ABSTRACT An attempt is made to explain the relationship of landslides to litho-tectonic and precipitation regimes. The possible influence of these factors on the dimensional pattern of landslides is also inferred. The Yamuna River valley, NW Himalaya, which traverses the Higher Himalaya (HH) and Lesser Himalaya (LH) rock mass, endures disastrous landslides and hence is taken as the case for study. To achieve the objectives, proxies like stream length gradient, topographic profile, steepness index, and ratio of valley floor width to valley height were used to infer a spatially varying tectonic regime, whereas rainfall data and Normalized Difference Vegetation Index were used to determine spatial differences in precipitation and vegetation variability, respectively. Dimensional patterns of landslides utilized the landslide area and volume. The higher reaches of the HH and lowest part of the LH show rockfall dominance associated with relatively high tectonic activity, whereas most of the debris slides coincide with regional thrusts. Total area and volume occupied by the landslides are ~1.5 ± 0.16 × 106 m2 and ~4.7 ± 1.2 × 106 m3, respectively. Dimensions of debris slides were found to be less influenced by the litho-tectonic and precipitation regimes, whereas the dimensions of rockfalls were found to be more sensitive to these conditions.

中文翻译：

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岩石构造和降水对山体滑坡的影响，亚穆纳河谷，喜马拉雅西北部

摘要 试图解释滑坡与岩石构造和降水制度的关系。还推断了这些因素对滑坡空间格局的可能影响。横跨高喜马拉雅山 (HH) 和小喜马拉雅山 (LH) 岩体的喜马拉雅西北亚穆纳河谷经历了灾难性的山体滑坡，因此被作为研究案例。为实现目标，使用河流长度梯度、地形剖面、陡度指数和谷底宽度与谷高比等代理来推断空间变化的构造状况，而降雨数据和归一化差异植被指数则用于确定空间差异分别在降水和植被变异方面。滑坡的维度模式利用了滑坡面积和体积。HH 的上游和 LH 的最低部分显示出与相对较高的构造活动相关的落石优势，而大多数碎屑滑坡与区域逆冲相吻合。滑坡的总面积和体积分别为~1.5 ± 0.16 × 106 m2 和~4.7 ± 1.2 × 106 m3。发现碎屑滑坡的尺寸受岩石构造和降水制度的影响较小，而落石的尺寸对这些条件更敏感。