Crustal Evolution of the Himalaya since Paleoproterozoic

Abstract

Understanding the crustal evolution of any orogen is essential in delineating the nomenclature of litho units, stratigraphic growth, tectonic evolution, and, most importantly, deciphering the paleogeography of the Earth. In this context, the Himalayas, one of the youngest continent-continent collisional orogen on the Earth, has played a key role in understanding the past supercontinent cycles, mountain building activities, and tectonic-climate interactions. This chapter presents the journey of Himalayan rocks through Columbian, Rodinia, and Gondwana supercontinent cycles to the present, as its litho units consist of the record of magmatism and sedimentation since ~2.0 Ga. The making of the Himalayan orogen started with the rifting of India from the Gondwanaland and its subsequent movement toward the Eurasian Plate, which led to the closure of the Neo-Tethyan ocean in the Late-Cretaceous. India collided with Eurasia between ∼59 Ma and ∼40 Ma. Later, the crustal thickening and shortening led to the metamorphism of the Himalayan crust and the development of the north-dipping south verging fold-and-thrust belt. The main phase of Himalayan uplift took place during the Late-Oligocene-Miocene. This chapter also provides insights into the prevailing kinematic models that govern the deep-seated exhumation of Himalayan rocks to the surface through the interplay of tectonics and climate.