Observation on the Structure of the Main Mantle Thrust at Jijal, Kohistan, Pakistan
Abstract
Structures in the lower part of the MMT at Jijal include a blastomylonite zone, Z-folds in the balstomylonite, and abundant slickensides in a breccia block. Blastomylonite foliation is cross-cut by intermediate granitic intrusive. A multi-stage history of the MMT involving (1) SE thrust motion on a deep shear zone, (2) uplift and granitic intrusion, (3) renewed thrust faulting and breccia formation at a shallow crustal level, and (4) folding of the MMT and cessation of thrust motion is suggested.
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