Tectonic study of the Sub-Himalayas based on geophysical data in Azad Jammu and Kashmir and northern Pakistan

Abstract

The tectonic study based on geophysical data has been carried out in Sub-Himalayas in Azad Jammu and Kashmir and northern Pakistan. A series of thin skinned and thick skinned faults have been delineated in the investigated area on the basis of present study. In the study area compressional stresses caused by the collisional of Indian and Eurasian plates developed the northwestsoutheast trending faults which are Shaheed Gala thrust, Bagh basement fault, Kashmir boundary thrust and Kawai fault or Indus Kohistan seismic zone. The crustal thickness increases towards north due to the stacking of the thrust sheets along these faults. The Murree Formation thrusts over the Siwaliks molasse along the Shaheed Gala thrust. This fault dips at an angle of 43º northeast and joins the thick skinned Bagh basement fault in subsurface which are penetrated up to Moho depth. In the northeast of Bagh basement fault the northwest-southeast trending Kashmir boundary thrust has been delineated in the sedimentary-metasedimentary wedge which joins the Indus Kohistan seismic zone in the subsurface. The present study suggested that the Kawai fault which is running within Murree Formation cuts 16 km thick sedimentary-metasedimentary wedge and also joins the Indus Kohistan seismic zone in the subsurface.

Keywords

tectonic study / Sub-Himalayas / Bouguer anomaly / magnetic anomaly / gravity modeling

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