Plate Tectonics and Mineralization of the Tethyan Ophiolite in the Southern Sanjiang and Indo-China Peninsular Area

The research about Tethys along the eastern boundary of the Qinghai-Tebit plateau arouses great interests of geologists from all over the world.However,geological jobs keep relatively inadequate and decentralized in the Sanjiang-Indo-China multinational area.Therefore,under the Tethyan tectonic background,it is significant to determine rules of tectonic geography and mineralization of the Tethyan ophiolite complex belt,and to discover the direct evidence of ocean plates based on the former research including its stratigraphy,petrology,structural geology and paleontology.Our study covers the following aspects: (1) The suture location and the subduction direction of different periods are concluded by connecting the tectonic magma belts with the orogenic belt.A geometric pattern of a more fragmentary ophiolite geography of the paleo-Tethys contrasting to that of meso-neo-Tethys can be found easily from the paleogeography.(2) The initial location of sutures greatly changed by events of Indo-Chinese epoch,Yanshanian epoch,and Himalayan epoch can be concluded from our research of the typical ophiolite outcrop area.(3) The formation and distribution of some important mineral resources are obviously controlled by the ophiolite complex belt.The ultra basic rock belts provide the ore material resources of magmatic cobalt and nickel metallogenic belt.The large area of acid magma formed during the course of the close and collision of plates,parallel to the ophiolite belt,is the important material resource of the hydrothermal wolfram and tin deposit belts.The formation of the regional hydrothermal deposits was improved by the transition of tectonic system around the Miocene.