新疆东天山西段却勒塔格蛇绿岩地球化学特征  

GEOCHEMICAL CHARACTERISTICS OF QUELETAGE OPHIOLITE IN THE WEST OF EAST TIANSHAN,XINJIANG

作　　者：朱志新[1] 田文全[2] 倪梁[3] 澎蔚兰[2] 冯新昌[2] 李嵩龄[2] 

机构地区：[1]中国地质大学研究生院,湖北武汉430074 [2]新疆维吾尔自治区地质矿产勘查开发局第一区域地质调查大队,新疆乌鲁木齐830011 [3]新疆维吾尔自治区国土资源厅,新疆乌鲁木齐830001

出　　处：《新疆地质》2004年第2期131-135,共5页Xinjiang Geology

摘　　要：新疆东天山西段乌什通沟—干沟蛇绿混杂岩带分布在干沟断裂南侧,该断裂是准噶尔板块与塔里木板块的分界面,该断裂北侧却勒塔格蛇绿岩围岩为古元古界变质深成岩(Sm-Nd全岩等时年龄(1 859±66)Ma)及白云岩、白云质大理岩、石墨大理岩和变质火山岩等.却勒塔格蛇绿岩以构造包体形式赋存在古变质岩中,镁铁质超基性岩具高Mg,贫Al、Ca、K、Na的特点,属阿尔卑斯型高钛蛇绿岩组合,形成时代为中晚震旦世(辉长岩Sm-Nd全岩等时年龄(728±110)Ma),闭合时代为中晚奥陶世.却勒塔格蛇绿岩和前震旦古变质岩的发现,具有重大地质意义。Wushitong-Gangou Ophiolit complex in east Tianshan of Xinjiang occurs in the south of the Gangou fault and formed the important interface between Junggar craton and Tarim craton. Queletage ophiolit was found in 2001 during the 1:50000 geological survey process. Its wallrock is earler proterozoic metamorphic plutonite( Sm-Nd isotope age for whole rock is 1859±66Ma), dolomite, dolomite marble, graphite marble and metamorphic volcanic rocks. Queletage ophiolite occurs as tectonic: enclave in age-old metamorphic rocks. Mafic ultrabasic rock which belongs to Alpine type high Ti ophiolite association and with forming age of middle-later Sinian ( Sm-Nd isotope age for gabbro is 728±111Ma), closing age of middle-later Ordovician, is characterized by high Mg, low Al, Ca, K and Na. The founding of Queletage ophiolite and Presinian metamorphic rocks is of important geological significance, which means that Aqikuduke fau t should occur at 2-3km north from Gangou fault in this area.

关 键 词：蛇绿岩 东天山 变质岩 地球化学特征 超基性岩 蛇绿混杂岩带 形成时代 山西 新疆 形式 

分 类 号：P588.3[天文地球—岩石学]