A timeline of the Cenozoic tectonic–magmatic–metamorphic evolution and development of ore resources in the Himalayas

Abstract

A large concentration of ore deposits (i.e., tungsten, tin, lithium, beryllium, lead, zinc, silver, antimony and gold) related to metamorphism and hydrothermal activity of granite developed in the Himalayas and are located in the southern part of the Qinghai‐Tibet Plateau. As one of the newest and largest examples in the world of continental–continental collisional orogenic belts, the Himalayas are optimal for studying the coupling of continental collisions with metamorphic, tectonic, magmatic events and ore resources. Although considerable research has been conducted in the Himalayas, the timing of various geological processes remains debated, which limits the understanding of the genesis of ore deposits. To better understand the influence of orogeny on the metallogenic process, this study comprehensively presents the time of activity of the above‐mentioned four Cenozoic geological processes in the Himalayas. This contribution focuses on the context of the timeline to determine the internal connections and discusses the interrelationships of the geological processes. This study argues that Cenozoic lower crust–mantle interactions deep within the Indian continental plate below the Himalayas controlled the tectonics, metamorphism, magmatism and mineralization in the middle–upper crust. Cenozoic magmatic rocks in the upper crust are the direct results of the main‐collisional and post‐collisional stages of the Indian and Eurasian continental blocks. Intense collisional shearing and metamorphism during the Eocene formed the Himalayan fault–fold Belt and orogenic gold deposits. The break‐off, detachment and slab tearing of the Indian lithosphere during the Miocene led to the extensional structure of the middle–upper crust. There is a close coupling relationship between the exhumation of the middle–lower crust and the formation of large‐scale leucogranites during the Miocene in the upper crust, which provides the geological context for the main metallogenic period during which tungsten, tin, lithium, beryllium, lead, zinc, silver, antimony and gold ore widely developed. With technological advancements, the analytical accuracy of geological ages has gradually improved. In the future, research on the temporal constraints of important geological activities should be strengthened, and then a comprehensive evolutionary model of multiple spheres of geological processes in the Himalayas should be established.