Subsurface Structural and Crustal Assessment on the Basis of Gravity Data Along Bagh, Dir Kot and Adjoining Areas of Azad Jammu and Kashmir, Pakistan

Abstract

The research work is based on gravity data is taken from numerous parts of an active tectonic belt of AzadKashmir to delineate the crustal thickness and demarcation of thin- skin and thick-skin structures in the study area. Thestudy area includes Bagh, Dhirkot, Arja, Kohala, Sudhan Gali, Ghazi Abad, Chikkar and Chakoti. The study areabounded by the latitude 33°59′3″ and 34°9′22″ N and longitude 73°37′26″ and 73°40′16″ E. The proposed study area isa complex geological entity and is an active zone. This study has been focused to assess the subsurface lithology andstructural geometry present in Bagh and surrounding areas. For this purpose the gravity data has been acquired with thehelp of CG-5 Auto-grav using multi-profile survey technique. Gravity model suggested that Riasi Thrust in the studyzone is plunging at an angle of 42° NE and pierces to a depth of 7 km in the sub-surface. The model also suggested thatBagh Basement Fault in the study area is dipping at an angle of 75° NE in the crystalline basement up to Moho depth.Shaheed Galli Thrust has been delineated in Dhirkot area. The fault dips at 49° NE and penetrated up to a depth of 8km in the sedimentary/meta-sedimentary wedge. The geological model demarcated, 11 km depth of sedimentary/metasedimentary wedge in the southwest and 13 km in the northeast area. The crustal thickness increases from 51 km in thesouthwest area to about 53.17 km in the northeast area.