扬子陆块西缘康定杂岩的形成时代和构造环境  

The Formation Age and Tectonic Setting of the Kangding Complex in the Western Margin of the Yangtze Block

作　　者：刘文中[1] 

机构地区：[1]安徽理工大学资源与环境工程系,安徽淮南232001

出　　处：《安徽理工大学学报（自然科学版）》2006年第4期1-5,共5页Journal of Anhui University of Science and Technology:Natural Science

基　　金：教育部科学技术研究重点资助项目(104089);安徽理工大学博士研究基金资助项目(2005YB51)

摘　　要：攀西麻粒岩是扬子陆块西缘康定杂岩的重要代表。通过对麻粒岩Rb—Sr、Sm—Nd、^40Ar／^39Ar和铬石U—Pb测年结果的比较，结合麻粒岩的变质演化历史和岩石地球化学特征分析，认为角闪岩相退变质作用对麻粒岩的Rb—Sr、Sm—Nd和^40Ar／^39Ar同位素计时体系产生了重要影响。多个岩体铬石U—Pb测年结果的一致性，表明康定岩浆—变质杂岩形成于新元古代（860～750Ma）。岩石的地球化学性质还指示了康定杂岩形成于扬子陆块西缘新元古代活动大陆边缘的岛弧环境。The Panxi granulite is the most important part of Kangding complex. The comparison research between Rb—Sr, Sm—Nd,^40Ar/^39Ar and zircon U—Pb dating results and the analysis of metamorphic evolution and litho-geochemical property of granulite indicates that the amphibolite-facies retrogressive metamorphism has an important effect on the Rb—Sr, Sm—Nd and ^40Ar/^39Ar isotopic timing system of granulites. The consistency of zircon U—Pb dating resulted from various rocks indicates that the Kangding magmatic and metamorphic complex were formed at the Neoproterozoic （860～750 Ma）period. The geochemical features of the Kangding complex also suggested that they were formed at the island arc tectonic setting of active continental margin at the Neoproterozoic period in the western margin of the Yangtze Block.

关 键 词：康定杂岩 构造环境 新元古代 扬子陆块西缘 

分 类 号：P59[天文地球—地球化学]