位处新疆东昆仑祁漫塔格地区的白干湖是中国西部最新探明的一个具超大型远景规模的钨锡矿田,柯可卡尔德是其中勘查程度最高、规模最大的钨锡矿床.文章在对柯可卡尔德钨锡矿地质特征详细野外调研和剖析的基础上,重点开展了控矿构造和白云母40Ar-39Ar定年研究.结果表明,该矿区内构造活动强烈且具多期次性,可划分为成矿前向西右旋剪切构造、成矿期以NE向为主的左旋张扭性断裂和成矿后近SN向正断层性质断裂等3期.应用白云母40 Ar-39 Ar同位素测年技术,分别测得了强云英岩化钨锡矿化花岗岩脉内白云母的积分年龄为(411.7±2.6) Ma,等时线年龄为(411.8±4.7) Ma(n=8,MSWD=0.21)；黑钨矿-石英脉垂直脉壁生长的片状白云母的积分年龄为(412.8±2.4) Ma,等时线年龄为(414.6±3.9) Ma(n=10,MSWD=0.22),厘定了该矿床的成矿时代为晚志留世,认为其形成于东昆仑地区加里东造山旋回的后碰撞构造阶段.%The Baiganhu W-Sn orefield, in the western part of the Qimantage mountains, eastern Kunlun orogenic belt, is the most recently discovered, large, W-Sn discovery in Xinjiang Uygur Autonomous Region, NW China. The orefield comprises four W-Sn ore deposits: Kekekaerde, Baiganhu, Bashierxi and Awaer. Of them, the Kekekaerde W-Sn deposit is largest and has highest exploration intensity. In this study, based on detailed field geological investigation, the ore-controlling structures and age determination on W-Sn ores have been carried out. The results show us that intensive and multi-stage structural activites had took place. They are, from early to late, right-lateral shear structure at pre-metallogenic stage, NE-striking predominately tenso-shear structure at metallogenic stage and nearly SN-striking normal fault at post-metallogenic stage. The 40Ar-39Ar incremental heating method was used to date, the results yield a40Ar-39Ar plateau age of (411.7±2.6) Ma and an isochron age of (411.8 ± 4.7) Ma with MSWD being 0.21 for muscovite separated from strongly greisenized W-Sn mineralization granite, a 40Ar-39Ar plateau age of (412.8 + 2.4) Ma and an isochron age of (414.6 ±3.9) Ma with MSWD being 0.22 for muscovite separated from quartz-wolframite vein with muscovite vertically growing along both walls of quartz vein, respectively. It is shown that the Kekekaerde W-Sn deposit was formed at late Silurian, corresponding to post-collisional stage during Caledonian tectonic cycle in eastern Kunlun area.
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