Geology of Hettangian to Middle Eocene Rocks of Hazara and Kashmir Basins, Northwest Lesser Himalayas, Pakistan

-The Mesozoic to Eocene sedimentary succession of Hazara Basin dominated by carbonates is characterized by a distinct package of sediments punctuated by a number of diastems, hiatus and unconformities. The Hazara Basin evolved in Hettangian with the development of lagoonal to upper shoreface conditions on the northern margin of northward flying India. It was followed by a thick pile of middle Jurassic to upper Cretaceous sediments representing deposition in supratidal to outer ramp settings. During late Cretaceous the basin was exposed subaerially when the Indian Plate established its first contact at 67±2Ma with the Kohistan Island Arc. During this time the Kashmir Basin remained exposed. Sedimentation resumed in Hazara and Kashmir basins with the development of transgressive shoreline and Hangu Formation was formed in Danian. The Hazara and Kashmir basins and adjacent areas experienced the last marine incursion at the close of Danian in which a sequence of carbonates and siliciclastics represented by Lockhart Formation, Patala Formation, Margala Hill Formation and Chorgali Formation were deposited. This was followed by main collision between India and Asia sandwiching the Kohistan Island Arc at 40 to 50Ma. This collision was followed by retreat of sea, uplift of Himalayas, development of a foredeep and deposition of a fluvial package, by meandering river system, from Himalayan provenance namely Murree Formation.