Tectono-stratigraphic evolution of the Upper Kaghan Valley, Northwestern Himalayas: insights from integrated field and remote-sensing analysis

The Himalayas were shaped when the Indian and Eurasian Plates collided, and active orogenic processes created the Upper Kaghan Valley, located in the Higher Himalayas. Earlier studies could not incorporate all the necessary geological, structural, and remote-sensing information for complete tectono-stratigraphic analysis. We present a single, unified tectono-stratigraphic column for the Upper Kaghan Valley built from 1:25,000 field mapping, quantitative structural analysis, cross-section preparation, and Sentinel-1 SAR. Three deformation phases are supported by kinematic indicators: F1 (NW–SE) gentle–open folds (layer-parallel shortening), F2 (NE–SW) tight, fault-propagation folding and back-thrusting, and F3 localized E–W doming. Integrating published geochronology, we correlate mapped granites with Ordovician S-type Mansehra-style plutonism (ca. 483–476 Ma), Cenozoic Kohistan Arc I-type granites (∼75–42 Ma), and Miocene Higher Himalayan Crystalline (HHC) leucogranites (∼21–17 Ma). Among many other faults, reverse thrust and back thrust faults are widely observed, which indicate current movement, turning over, and shaping of the valley, most associated with Tertiary granites. Fieldwork and remote sensing were combined to better understand the structure and types of rocks in the Himalayan orogeny. The resulting framework constrains the sequence of deformation and uplift along the Main Central Thrust (MCT) to the Main Mantle Thrust (MMT) and provides targets for mineral prospectivity.