新疆准噶尔北缘玉勒肯哈腊苏铜(钼)矿区韧性剪切变形时代--来自白-云-母和黑云母Ar-Ar年龄的约束  

Ar-Ar Dating of the Ductile Shear Zones in the Yulekenhalasu Cu-(Mo) Ore Deposit

作　　者：杨富全[1] 秦纪华[2] 刘锋[1] 张志欣[3] 刘振江[2] 耿新霞[1] 柴凤梅[4] 高文娟[5] 

机构地区：[1]中国地质科学院矿产资源研究所,国土资源部成矿作用与资源评价重点实验室,北京100037 [2]新疆地质矿产勘查开发局第四地质大队,新疆阿勒泰836500 [3]中国科学院新疆生态与地理研究所,新疆矿产资源研究中心,新疆乌鲁木齐830011 [4]新疆大学新疆中亚造山带大陆动力学与成矿预测实验室,新疆乌鲁木齐830046 [5]河北省地矿局探矿技术研究院,河北三河065201

出　　处：《大地构造与成矿学》2013年第1期1-10,共10页Geotectonica et Metallogenia

基　　金：国家自然科学基金项目(批准号:40972069)资助

摘　　要：玉勒肯哈腊苏斑岩铜(钼)矿主要赋存于闪长玢岩中,少量在北塔山组火山岩及似斑状石英二长岩中。矿化呈细脉状、细脉-浸染状和浸染状。成矿过程经历了斑岩期、剪切变形期和表生期。矿区发育韧性剪切变形带,中泥盆统北塔山组、下石炭统姜巴斯套组、岩体及矿体均发生了剪切变形作用。沿剪切面发育黑云母和白云母新生矿物。白云母的坪年龄和等时线年龄分别为283.8±1.5Ma和285.4±3.1Ma,黑云母的坪年龄和等时线年龄分别为277.0±2.0Ma和277.0±4.0Ma,在误差范围内基本一致,限定矿区韧性剪切变形时间在早二叠世(284～277Ma),与区域额尔齐斯-玛因鄂博断裂活动时间一致。主要成矿作用形成于斑岩期,成矿时代为中泥盆世(374Ma),早二叠世的韧性剪切变形作用只对铜(钼)矿化进行改造。The Yulekenhalasu porphyry copper-（ molybdenum） deposit occurs in the diorite porphyry, porphyroid quartz monzonite, and volcanic rocks of the Beitashan Formation. Mineralization occurs as veinlet, veinlet- dissemi- nated and stoekwork. The ore-forming processes can be divided into three mineralization periods： porphyry, shear deformation and supergene. The ductile shear zones are well developed in the Yulekenhalasu ore district, and the strata of the Middle Devonian Beitashan Formation and Lower Carboniferous Jiangbasitao Formation, intrusives and orebodies. The shearing related muscovite and biotite occurred in the shear surface. ^40Ar/39Ar dating was performed on the muscovite and biotite, which yielded two plateau ages of 283.8 ± 1.5 Ma and 277.0 ± 2.0 Ma, and isochron ages of 285.4 ± 3.1 Ma and 277.0 ±4.0 Ma, respectively. Two plateau ages are coincident with the isochron ages within error, which reflect the ductile shearing deformation in the ore district took place in the Early Permian （284 ±277 Ma）. The ductile shearing deformation age in the Yulekenhalasu ore deposit is coincident with the age of Ir- tysh-Mayinebo fault belt. The porphyry Cu-（Mo） mineralization took place in the Middle Devonian （374 Ma）, while the ductile shearing deformation in the Early Permian reformed the Cu-（Mo） ore deposit.

关 键 词：韧性剪切带 Ar—Ar年龄 斑岩型铜(钼)矿床 玉勒肯哈腊苏 准噶尔北缘 

分 类 号：P542[天文地球—构造地质学]