Tectonic Unit Division and Geological Evolution of Pakistan and Its Adjacent Regions

Pakistan is located in the middle section of the Tethyan tectonic domain, where is the junction of India plate, Eurasian plate and Arabian plate, thus it serves as one of the hot spots for studying the Himalayan orogeny and Tethys tectonic domain. Based on the previous studies, the tectonic units of Pakistan and its adjacent regions has been divided, and their geological evolution has been discussed, which provide some basic data for the geosciences comparative study of the border region in China and Pakistan. This studying area has been divided into 3 first-order tectonic units (Karakum-Tarim plate, Middle Iran-Gangdese intermediate plate and Indian plate), 13 secondary tectonic units and 11 third-grade tectonic units by taking Bamiyan-Kangxiwa suture and Kohistan-Ladakh suture as the boundaries, and then the geological characteristics of these tectonic units have been introduced. Finally, the evolution of this studying area has been discussed from the formation and evolution of Paleo-and Neo-Tethys Oceans, as well as the continent-continent collision. During the evolution process of Paleo-and Neo-Tethys Oceans, South Pamir, Qiangtang and Lhasa blocks were separated from the north margin of Gondwana supercontinent, and then the Bamiyan-Kangxiwa, Kohistan-Ladakh, Yarlungzangbo sutures, Main Karakorum and Main Mantle faults were formed successively, which constitute the main tectonic framework of this studying area. During the continent-continent collision orogeny process, a series of fault systems and related rifting systems or rifting basins were formed by the crustal extension and rifting, which reconstruct the edge and shape of original sedimentary basin and control the emplacement and spatial distribution of various rocks.