四川米易海塔地区前震旦纪五马箐组变质作用P-T条件研究  

P-T conditions of metamorphism of the Pre-Sinian Wumaqing Formation in Haita Area,Miyi County,Sichuan Province

作　　者：范伟 陈友良[1,2] 欧何琼 顾孟娟 付于真[1] 张宝玲 詹国鑫 FAN Wei;CHEN Youiang;OU Heqiong;FU Yuzhen;GU Mengjuan;ZHANG Baoing;ZHAN Guoxin(College of Earth Sciences,Chengdu University of Technology,Chengdu 610059,Sichaun,China;Key Labora-tory of Applied Nuclear Techniques in Geosciences of Sichuan Province,Chengdu 610059,Sichaun,China)

机构地区：[1]成都理工大学地球科学学院,四川成都610059 [2]成都理工大学地学与核技术四川省重点实验室,四川成都610059

出　　处：《四川冶金》2023年第4期18-24,共7页Sichuan Metallurgy

基　　金：中国核工业地质局重点科研项目"康滇地轴前寒武纪地质构造演化及其对铀成矿的制约"(编号:2023一16);成都理工大学珠峰科技计划(编号:2022ZF11413)联合资助。

摘　　要：在扬子板块西缘的康滇陆块上分布有一套变质程度深浅不一的前震旦纪变质岩系,长期以来对这套变质岩的温压条件研究相对薄弱。笔者等以四川米易海塔地区前震旦纪五马箐组中的黑云斜长角闪片岩为研究对象,通过岩相学、矿物化学分析、变质P-T条件计算,结果表明:黑云斜长角闪片岩峰期矿物共生组合为角闪石+黑云母+斜长石+石英+榍石,其峰期变质条件为T=599℃,P=0.22 Gpa,其变质相为角闪岩相。米易海塔地区前震旦纪五马箐组经历了中温低压型变质作用,可能形成于新元古代地幔柱活动时期的裂谷环境。There is a set of pre-Sinian metamorphic rock series with varying degrees of metamorphism in Kang-Yun-nan block on the western margin of the Yangtze plate.The study on the temperature and pressure conditions of these metamorphic rocks is relatively weak.Taking the pre-Sinian Wumaqing Formation in Haita area,Miyi Coun-ty,Sichuan Province as the research object,the author et al.,by means of petrography,mineral-chemical analysis,metamorphic P-T condition calculation,the results show that:The mineral association of the peak period of the pla-gioclase amphibolite was hornblende+biotite+plagioclase+quartz+sphene.The metamorphic conditions of the peak period were T=599℃,P=0.22Gpa,and themetamorphic phasewashornblendefacies.Thepre-Sinian Wu-maqing Formation,Haita area,Miyi County,underwent mesothermal and low-pressure metamorphism and may have been formed in the rift environment during the Neoproterozoic mantle plume activity.

关 键 词：前震旦纪 五马箐组 黑云斜长角闪片岩 P-T条件 海塔地区 

分 类 号：P575[天文地球—矿物学]