MECHANISM OF THE BASIN-MOUNTAIN METALLOGENIC SYSTEM IN HIMALAYAN PERIOD IN SANJIANG CONCENTRATION AREA,SOUTHWEST CHINA

Sanjiang (Jinshajiang River,Lancangjiang River and Nujiang River) concentration area in southwest China is within the Tethys\|Himalayan tectonic domain,and it is the main area where develops Himalayan movement and relative ore deposits,such as Yulong super large Cu\|Mo deposit,Jinding super large Pb\|Zn deposit,etc ,in West China.So it is a best place to study Himalayan movement and metallogeny.1 Metallogenic geological background Sanjiang concentration area has passed complex Tethys tectonic development before Cainozoic era,and it begins Himalayan inland basin\|mountain tectonic development at the end of Yanshan movement.It commonly accepts autochthonous platform type deposits since Mesozoic era,and the basin\|mountain tectonic pattern has already appeared.Old metamorphic terrains and paleo\|Tethys orogenic belts become “mountains”,as well as microplateforms sink to become “basins”.Comparing to Mesozoic basins,Eogene basins are many smaller garben\|type extension basins or strike\|slip extension basins on the background of big large basins.