Overriding the underthrusting Indian plate along the low angle detachment surface of the Main Himalayan Thrust (MHT), the entire Himalayan wedge, consisting of several allochthonous and autochthonous sheets is actively deforming due to ongoing India-Asia convergence. However, the information on active tectonics of autochthonous sheets exposed in tectonic windows has often been eluded due to lack of directed investigations. The present study pertains to the active tectonics of the eastern part of an autochthonous sheet exposed in Kullu-Larji-Rampur window of the Lesser Himalaya. Geomorphic features and statistically analyzed geomorphic indices of Drainage Basin Shape (Bs), Hypsometric Integral (HI), Stream Length-Gradient Index (SL), Transverse Topography Symmetry Factor (T), and Basin Asymmetry Factor (AF) reveal active crustal deformation in the window caused by tectonic activities of spatially varying magnitudes. While the spatial distribution of Bs, HI, and SL suggest differential uplift of the anticlinally folded autochthonous sheet along the MHT, the spatial distributions of AF and T suggest an overall southeastward preferential shifting of the trunk streams of 3rd-order drainage basins of the terrane; the hinge zone and northwestern part of the sheet are experiencing relatively faster uplift. The faster uplift in the northwest has caused an overall southeastward down-tiling of the terrane, and thus preferential stream migration in that direction. The faster uplift of the hinge zone is considered to indicate active tightening of the fold.

沿着主喜马拉雅逆冲断层 (MHT) 的低角度脱离表面覆盖下冲的印度板块，整个喜马拉雅楔形体由几个异地和本土板块组成，由于持续的印度-亚洲辐合而正在积极变形。然而，由于缺乏有针对性的调查，在构造窗口中暴露的本土板块的活动构造信息经常被忽略。本研究涉及出露在小喜马拉雅山 Kullu-Larji-Rampur 窗中的本土板块东部的活动构造。流域盆地形状（Bs）、测高积分（HI）、河流长度梯度指数（SL）、横向地形对称因子（T）的地貌特征和统计分析地貌指数，和盆地不对称因子（AF）揭示了由空间变化幅度的构造活动引起的窗口中的活跃地壳变形。Bs、HI 和 SL 的空间分布表明沿 MHT 背斜折叠的本土片层有差异抬升，而 AF 和 T 的空间分布表明地体三级流域干流总体向东南优先移动; 铰接带和板块的西北部正在经历相对较快的隆升。西北部较快的隆升导致地体整体向东南下倾，从而优先向该方向迁移。铰链区的快速上升被认为表明褶皱的主动收紧。Bs、HI 和 SL 的空间分布表明沿 MHT 背斜折叠的本土片层有差异抬升，而 AF 和 T 的空间分布表明地体三级流域干流总体向东南优先移动; 铰接带和板块的西北部正在经历相对较快的隆升。西北部较快的隆升导致地体整体向东南下倾，从而优先向该方向迁移。铰链区的快速上升被认为表明褶皱的主动收紧。Bs、HI 和 SL 的空间分布表明沿 MHT 背斜折叠的本土片层有差异抬升，而 AF 和 T 的空间分布表明地体三级流域干流总体向东南优先移动; 铰接带和板块的西北部正在经历相对较快的隆升。西北部较快的隆升导致地体整体向东南下倾，从而优先向该方向迁移。铰链区的快速上升被认为表明褶皱的主动收紧。AF和T的空间分布表明地体三级流域干流总体向东南优先移动；铰接带和板块的西北部正在经历相对较快的隆升。西北部较快的隆升导致地体整体向东南下倾，从而优先向该方向迁移。铰链区的快速上升被认为表明褶皱的主动收紧。AF和T的空间分布表明地体三级流域干流总体向东南优先移动；铰接带和板块的西北部正在经历相对较快的隆升。西北部较快的隆升导致地体整体向东南下倾，从而优先向该方向迁移。铰链区的快速上升被认为表明褶皱的主动收紧。