Emplacement of the Bibai and Gogai Nappes, Northeast of Quetta
Abstract
Emplacement of the nappe structures has been studied in an area ENE of Quetta. The area is underlain by sedimentary rocks of Mesozoic and Cainozoic era with minor volcanic intercalations. Two large thrust sheets, i.e. the Bibai and Gogai nappes, were emplaced between Middle Eocene and Early Oligocene epochs. The Gogai nappe is a hinterland dipping duplex in which thrusting was in piggyback fashion while a blind imbricate zone is present along the Bibai thrust.
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