新疆-甘肃-内蒙古衔接区古生代构造背景与成矿的关系

新疆-甘肃-内蒙古衔接区可划分为星星峡-旱山微板块和敦煌微板块,二者以红柳河-牛圈子-洗肠井缝合带为界。古陆裂解初期的寒武纪浅海—次深海具有形成磷钒铀锰沉积矿产的有利背景;奥陶纪洋盆及弧后盆地具备形成与海相火山-沉积岩系有关铜矿的有利背景;志留纪—泥盆纪岛弧火山建造具备形成斑岩铜矿的有利背景;石炭纪—二叠纪陆内裂谷具备形成火山沉积铁矿、铜矿、斑岩铜矿和与基性超基性岩有关铜镍矿的有利背景;各单元古陆壳活化重熔型花岗岩具有形成钨锡稀有金属矿的有利背景。

The relationship between Paleozoic tectonic setting and mineralization in Xinjiang-Gansu-Inner Mongolia juncture area

The Xinjiang-Gansu-Inner Mongolia juncture area is divided into two parts,i.e.,Xingxingxia-Hanshan micro-plant and Dunhuang micro-plant,and the suture line between them is Hongliuhe-Niujuanzi-Xichangjing ophiolite belt.Paleozoic tectonic evolution of the area underwent three stages： Sinian-Ordovician belonged to the old landmass divergence and ocean basin spreading stage,Silurian-Devonian belonged to the plate subduction and collision-orogeny stage,and Carboniferous-Permian belonged to the continental rift stage.In Cambrian,the shallow marine basin of old landmass was divergent frequently,and sedimentary deposits could be formed,such as phosphorus-vanadium-uranium-manganese mineral resources.In Ordovician ocean basin and back-arc basin,volcano-sedimentary type copper-zinc minerals could be formed,and Silurian-Devonian island-arc volcanic formation might serve as host rock of porphyry copper deposits.The volcano-sedimentary type iron deposits probably occurred in Carboniferous-Permian continental rift sedimentary formation,and porphyry copper deposits and copper-nickel deposits of basic rock type could be formed.The palaeocontinunt crust melting type granite mass constituted favorable background for the formation of metallogenic W,Sn and rare metal deposits.