新疆阿尔泰—准噶尔北缘晚古生代构造演化和内生金属矿床成矿系列

Late Paleozoic tectonic evolution and metallogenic series of endogenetic metal deposits in Altai and North Jungar

阿尔泰是中亚成矿域重要的内生金属矿产集中区,该矿集区晚古生代发育有5类内生金属矿床:1)块状硫化物Cu-Pb-Zn矿床,2)斑岩型Cu-Au矿床,3)岩浆Cu-Ni硫化物矿床,4)矽卡岩型Cu-Mo-Fe矿床,5)造山型金矿床和伟晶岩型稀有金属矿床。在构造上,这些矿床的形成与阿尔泰造山带俯冲—增生作用密切相关。阿尔泰晚古生代矿床的形成可以划分为3个主要阶段:Ⅰ)早-中泥盆世,沿阿尔泰南缘古生代活动大陆边缘弧后伸展,导致在阿尔泰西部琼库尔—塔拉特地质体中形成的多金属火山成因块状硫化物矿床,以及阿尔泰东段铁—铜矽卡岩矿床;Ⅱ)石炭纪—二叠纪的地体增生和弧岩浆作用,在布尔津—二台和额尔齐斯地体中形成了广泛分布的斑岩型矿床、岩浆铜镍硫化物矿床,在额尔齐斯地体中形成的铜铁矽卡岩矿床;Ⅲ)早二叠世的持续增生导致阿尔泰南部的杜拉特岛弧形成,并伴随有矽卡岩铜钼矿床和造山型金矿的形成;晚二叠世阿尔泰地区进入造山带演化阶段,并发生区域动力热流变质作用和片麻岩穹隆,伴随有花岗岩化和重熔岩浆活动和大量伟晶岩矿床的形成。晚古生代阿尔泰南缘的俯冲—增生构造演化过程,导致了不同类型内生金属矿床的形成,构成了我国重要的内生金属矿集区和矿山后备基地。

The Altai and North Jungar is an important endogenetic metallogenic area in the central Asia orogenic belt.There are five types of endogenetic metal deposits in the Late Paleozoic in this area:1)massive sulfide Cu-Pb-Zn deposits,2)porphyry Cu-Au deposits,3)magmatic Cu-Ni sulfide deposits,4)skarn Cu-Mo-Fe deposits,and 5)orogenic gold deposists.These deposits correspondingly constitute five metallogenic series.Structurally,the formation of these deposits is closely related to subduction-accretion in the Altai orogenic belt.Altai late Paleozoic formation of ore deposit can be divided into three main stages:Ⅰ)Late Devonian to Early Carboniferous epoch,along the southern margin of the Altay Paleozoic active continental margin arc after stretching,resulting in the Altai formed in the western Qiongkuer-Talate specially plastid volcanic cause massive sulfide polymetallic deposit,and the eastern Altai iron-copper skarn deposit;Ⅱ)during the Carboniferous to Permian terrane accretion and arc magmatism,porphyry deposits and magmatic Cu-Ni sulfide deposits were widely distributed in the Puerjin-Ertai and Irtysh terrains,and Cu-Fe skarn deposits were formed in the Irtysh Basin;Ⅲ)the Permian continued accretion led to the development of Dulate arcs in southern Altai and the formation of Cu-Mo skarn deposits and orogenic gold deposits.The subduction-accretion tectonic evolution process in the southern margin of the Late Paleozoic Altai resulted in the formation of different types of endogenous metal deposits,and different tectonic evolution stages led to the formation of different deposits,forming an important endogenous metal deposit concentration area and mine reserve base in China.