新疆西昆仑北缘叶城棋盘-西河休一带构造岩浆活动与成矿关系

Tectonic Magmatic Activity in Relation to Mineralization in the Yecheng-Xihexiu area,Northern Margin of the West Kunlun,Xinjiang

新疆叶城地区处于西昆仑弧盆系和塔里木地台的衔接地带,横跨铁克里克与西昆仑两大成矿带,近年来发现一批与岩浆活动有关的热液型矿床(点),显示出较好的成矿前景。在总结已有矿床(点)基本特征和相关岩浆活动的基础上,结合高精度成岩成矿年龄数据,叶城地区岩浆活动可分为古元古代、早古生代和晚古生代三期岩浆活动,其中早古生代岩浆活动主要发育于西昆仑地块上,从寒武纪到志留纪,形成一个较完整的岩浆演化旋回,与特提斯洋裂解、扩展和消亡的循环密切相关。并将与构造岩浆活动有关的矿点(床)划分为早古生代与老结晶基底、岩浆作用有关的Pb、Zn-Fe-玉石矿成矿系列,早寒武世与基性火山作用有关的Au-Cu成矿系列,晚泥盆世与构造岩浆活动有关的Pb、Zn-Cu成矿系列。早古生代(尤其是奥陶纪)是研究区大规模的成矿期,形成与中酸性岩浆活动有关的沉积-热液改造型铅锌矿、矽卡岩型铁矿、接触变质型玉石矿等。

The Yecheng area of Xinjiang is located in the junction between the West Kunlun arc basin and Tarim platform,which crosses two large metallogenic belts of the Tiekelike and the West Kunlun.In recent years,a number of hydrothermal deposits(spots)related to magmatism have been discovered there,indicating a better prospect of metallogenic deposits.The magmatic activity in the Yecheng area can be divided into three periods:Paleoproterozoic,Early Paleozoic,and Late Paleozoic based on existing ore deposits(points)and related magmatism in combination with high precision diagenetic mineralization ages.There into,the Early Paleozoic magmatic activity occurred on the West Kunlun block from Cambrian to Silurian,forming a relatively complete cycle of magma evolution,which was closely related to the cycle of the Tethys Ocean's breaking,extension and subduction.The ore spots(deposits)related to tectonic magmatism can be divided into three metallogenic series:①Early Paleozoic Pb-Zn-Fe-jade ore metallogenic series related to old crystalline basement and magmatism.②Early Cambrian Au-Cu metallogenic series associated with basic volcanism.③Late Devonian Pb-Zn-Cu metallogenic series related to tectonic magmatism.To sum up,Early Paleozoic(especially the Ordovician)is a large-scale mineralization period in the study area,during which formed sediment-hydrothermal reform-type lead-zinc ore associated with intermediate-acid magmatism,skarn iron ore,contact metamorphic type jade ore and so forth.