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The Suru, Doda and Zanskar river valleys in the semi-arid region of Southern Zanskar Ranges (SZR) preserve a rich repository of the glacial and fluvial landforms, alluvial fans, and lacustrine deposits. Based on detailed field observations, geomorphic mapping and limited optical ages, we suggest four glaciations of decreasing magnitude in the SZR. The oldest Southern Zanskar Glaciation Stage (SZS-4) is inferred from glacially polished bedrock and tillite pinnacles. The SZS-4 is ascribed to the Marine Isotopic Stage (MIS)-4/3. The subsequent SZS-3 is represented by obliterated and dissected moraines, and is assigned to MIS-2/Last Glacial Maximum. The multiple recessional moraines of SZS-2 glaciation are assigned the early to mid Holocene age whereas, the youngest SZS-1 moraines were deposited during the Little Ice Age. We suggest that during the SZS-2 glaciation, the Drang-Drung glacier shifted its course from Suru Valley (west) to the Doda Valley (east). The study area has preserved three generations of outwash gravel terraces, which broadly correlate with the phases of deglaciation associated with SZS-3, 2, and 1. The alluvial fan aggradation, lacustrine sedimentation, and loess deposition occurred during the mid-to-late Holocene. We suggest that glaciation was driven by a combination of the mid-latitude westerlies and the Indian Summer Monsoon during periods of cooler temperature, while phases of deglaciation occurred during enhanced temperature.

The Katrol hill fault (KHF) is a 71 km long fault, striking E-W in the Kachchh intraplate region, western India which is moderately active, seismically, but exhibit high strain rate with considerable vertical deformation. It is dissected by several young transverse faults. Based on these transverse faults, KHF is longitudinally, divided into five segments. Even though there are evidences of its active nature during the Holocene Period, no studies have been carried out for quantifying the spatial variation in relative tectonic activity along the KHF, which is vital for assessing a more realistic seismic hazard potential of the fault. Quantitative geomorphic indices are employed to evaluate the ‘Relative Index of Tectonic Activity (RITA)’. It has been observed that the central part (segment 2 & 3) is the most active segment, which covers an aerial extent of 38% of total KHF (class 1), compared to the eastern (segment 4 & 5) and the western segments (segment 1), which are moderately active (class 2). Interestingly none of the segments of the KHF, corresponded to class 3 of RITA i.e. least active/inactive class. The study highlights the important role of transverse faults, which cut across the major E-W faults in the Kachchh, and may regulate the relative activity and the earthquake potential of an individual segment. The study thus, hints the KHF as an under-rated source for future seismic hazard for the Kachchh and western India region.