Newly identified Active Faults in the Peshawar Basin
Keywords:
Keywords: Peshawar Basin, Active Faults, Digital Evaluation Mode (DEM), Alluvial deposits, and Active deformation.Abstract
Recent studies reveal that the Peshawar Basin, in the northwestern region of the Himalayas, is actively deforming in response to the ongoing tectonics of the Himalayas. Geological research on the Peshawar Basin has been limited despite thousands of reported low to moderate-magnitude earthquakes over the past two decades. After analyzing the Digital Elevation Model (DEM), seismic data, and geophysical data along with field observations, we have been able to identify six active faults that extend from the Southeast to the Northwest. Between 1978 and 2018, several earthquakes with a magnitude greater than 5 indicate neotectonics activity in the Peshawar Basin. Previous research has identified active faults only in the southern region of the Basin. This study presents a comprehensive mapping of active faults in the Peshawar Basin. These identified faults cut through the towns with the highest population density, given that the Peshawar Basin has only 10% of the exposed rocks. Field observations and fracture data from various infrastructures
confirm that the Ghorghasti and Pir Sabak faults are thrust faults, while the Charsadda-Takhbhai, Mardan, Pir Piai, and Swabi faults are normal faults. Moreover, the alluvial deposits show normal faults and anticlinal folds, indicating widespread active deformation along these fault lines.
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