Gravity and magnetic studies in the region of Main Boundary Thrust, west of Himalayan Syntaxis
Abstract
The interpretation of gravity measurements in the west of Hazara Kashmir syntaxis, particularly around Main Boundary Thrust region suggests that the crustal thickness in the region is around 47km, and the Moho dips at an angle around 1.0 degree towards northeast against the calculated dip of about 4.0 degrees just south of Margala ranges. The residual gravity which corresponds reasonably to a generalized lithostructural model of the area predicts also some anomalous situation which get support from magnetic results. The density modelling along Islamabad-Haripur section gives the possibility of existence of basement or ultra-basic slices near Islamabad at a depth of 5km. Further, the MBT and Langrial faults seem to be changing dips downwards to 25o or more.
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