Geomorphic assessment of active tectonics in Jaisalmer basin (Western Rajasthan, India)

Abstract

The northwestern part of Indian plate consists of a number of sedimentary basins such as the Jaisalmer basin with Early Jurassic to Quaternary deposits. The NW-SE trending Kanoi fault and Ramgarh fault with Mari-Jaisalmer Arch in the basin are tectonically active. We delineate the tectonically active areas of the basin by considering watersheds, micro-scale basins and spot locations. Analytic Hierarchy Process (AHP) is applied to calculate the Index of Active Tectonics (IAT) for the watersheds. Basin asymmetry (AF), valley floor width to height ratio (Vf) and hypsometric curve are calculated/generated. Computed R2 values and the IAT identify watershed-4, Miajlai depression, to be tectonically most active. Three individual spots along the NW-trending Mari highland have tectonic control on drainage patters. The hydrocarbon fields are located in the Shahgarh and the Miajlar depression zones within watersheds 3 and 4, which are under tectonically moderate and high activities, respectively. Highlights Geomorphology of the Jaisalmer basin in response to active tectonics is investigated. Watershed 4 is tectonically active followed by watershed 3. Hydrocarbon fields are located in these two watersheds. The work will have far-reaching implication in petroleum geosciences of the area.