南天山蛇绿混杂岩和中天山南缘糜棱岩的^(40)Ar/^(39)Ar年龄及其大地构造意义  

^(40)/^(39)Ar DATING OF THE OPHIOLITE MELANGE IN SOUTHERN TIANSHAN AND THE MYLONITE IN THE SOUTHERN RIM OF CENTER TIANSHAN AND THEIR TECTONIC SIGNIFICANCE

作　　者：蔡东升[1] 卢华复[1] 贾东[1] 吴世敏[1] 陈楚铭[1] 

机构地区：[1]南京大学地球科学系,南京210008

出　　处：《地质科学》1996年第4期384-390,共7页Chinese Journal of Geology(Scientia Geologica Sinica)

基　　金：国家重点攻关项目85-101-01-01

摘　　要：^(40)Ar/^(39)Ar同位素年龄测定,获得南天山蛇绿混杂岩基质黑云母石英片岩单矿物黑云母的两个坪年龄分别为(370.0±4.8)Ma和(259.0±3.3)Ma;中天山南缘长英质糜棱岩单矿物黑云母的坪年龄为(250.5±7.9)Ma,二云母花岗岩单矿物白云母的坪年龄为(348.9±0.3)Ma。结合南天山古生代沉积特征和塔里木及伊犁-哈萨克斯坦板块古地磁数据的综合分析,提出南天山晚泥盆世至石炭纪早期完成向伊犁-哈萨克斯坦板块的B型俯冲,中-晚二叠世进行陆内A型俯冲造山的板块碰撞演化模式。40Ar /39Ar age data on the ophiolite melange in Southern Tianshan and the mylonite and collisional granite in the southern rim of Center Tianshan indicate that the Tarim plate sould have collided with Yili-Kazakhstan plate during late Devonian - early time of early carboniferous period, creating a relic epicontinental sea basin or bay opening to the west in the west of Southern Tianshan. This sea basin closed during middle-late Permian which was related with the orogeny of the intracontinental A-type subduction after a B-type.

关 键 词：蛇绿混杂岩 糜棱岩 氩同位素 年龄 地质构造 

分 类 号：P588.36[天文地球—岩石学] P588.332[天文地球—地质学]