The Ashele Cu-Zn (VMS) deposit is located on the southwest margin of the Altay orogen, north of the Maerkakuli deep fault in the Ertix Hercyian orogenic zone. The deposit occurs in volcanic rocks and pyroclastic rocks of the Middle and Lower Devonian Ashele Formation. After the main exhalative-sedimentary ore-forming stage, the deposit underwent metamorphic reformation, hydrothermal superimposition and supergene oxidation. The brittle ductile shear structures such as schistosity, stretching lineation, S-C fabrics, rotational porphyroclast, asymmetric pressure shadows, flow cleavage, zonal extinction of quartz are well developed in the Ashele Cu-Zn deposit.40Ar/39Ar dating of sericite formed in the brittle ductile shear zone yielded isochron age of (251.6±2.9) Ma and plateau age of (251.2±1.6) Ma. The isochron age is coincident with the plateau age within the error range, which suggests that the timing of brittle ductile shearing deformation in the ore district is the Late Permian–Early Triassic, later than the main ductile shearing deformation age of Ertix sinistral strike-slip regional fault belt. The main metallogenic stage of the Ashele deposit occurred in the Early–Middle Devonian, and Late Permian–Early Triassic brittle ductile shear deformation played some transformation role in the deposit.%新疆阿舍勒 VMS 型铜锌矿位于阿尔泰造山带西南缘的阿舍勒盆地,额尔齐斯深断裂的次级玛尔卡库里大断裂带以北,矿床赋存于下—中泥盆统阿舍勒组火山岩系中。矿床在主成矿期喷流-沉积阶段形成之后,遭受岩浆热液叠加、剪切变形作用改造以及表生氧化作用。片理、拉伸线理、S-C面理、旋转碎斑、黄铁矿不对称压力影、流劈理、石英带状消光及扭裂等剪切变形构造在矿区普遍发育。本文通过对脆-韧性剪切作用形成绢云母的40Ar/39Ar同位素测年获得等时线年龄和坪年龄分别为(251.6±2.9) Ma和(251.2±1.6) Ma,在误差范围内基本一致,从而限定矿区脆韧性剪切带形成时间为晚二叠世—早三叠世,为额尔齐斯断裂区域大规模剪切-走滑活动后的局部剪切运动。阿舍勒铜矿主成矿期形成于早泥盆世末期—中泥盆世,晚二叠世—早三叠世韧性剪切变形对矿床具有一定的改造作用。
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