攀枝花米易普威地区康定群地层变质作用特征研究  

Research on Metamorphism of the Kangding Group in the Miyi-Puwei Region,Sichuan

作　　者：梁兵 邓红 罗林洪 LIANG Bing;DENG Hong;LUO Lin-hong(No.108 Geological Team,BGEEMRSP,Chengdu 611230)

机构地区：[1]四川省地质矿产勘查开发局一0八地质队,四川崇州610000

出　　处：《四川地质学报》2020年第4期544-550,共7页Acta Geologica Sichuan

摘　　要：扬子地台西缘(即传统意义的“康颠地轴”)是华南前寒武纪地质研究的重要地区之一,其中康定群为“双层基底结构”中结晶基底的重要组成部分,区域变质作用普遍。本文选取四川省米易县普威镇一带的康定群(HtKD)的咱里组(Htzl)及冷竹关组(Htlz)地层作为研究对象,通过薄片鉴定、岩石化学、电子探针等手段对康定群变质作用进行了详尽研究,认为中条运动使增生陆核汇聚,地幔上隆,岩浆增生产生高地热梯度,汇聚应力促成强烈的构造活动,使咱里组(Htzl)及冷竹关组(Htlz)发生了动力热流变质(形成高绿片岩相的铁铝榴石带与低角闪岩相斜长石-普通角闪石带),变质时代为中条期,而随着板块之间的(Rodinia大陆)汇聚,俯冲碰撞的加剧,研究区又发生了强烈的晋宁造山运动,在这个过程中以低温动力变质作用为主,使岩石叠加了低绿片岩相的退变质。Research on metamorphism of the Kangding Group by means of rock thin section observation,petrochemistry and electron probing analysis indicates that the Zhongtiao movement made the Zanli Formation(Htzl) and Lengzhuguan Formation(Htlz) in the Miyi-Puwei region underwent dynamic thermal metamorphism,forming almandine belt of high-green schist-facies and amphibolite-plagioclase belt of low-green schist-facies during the middle Zhongtiao epoch, while low-temperature dynamic metamorphism in the Jinning epoch resulted in superimposed retrograde metamorphism of the low green schist facies.

关 键 词：米易康定群 变质岩 变质时代 结晶基底 

分 类 号：P588.33[天文地球—岩石学]