大别山区含柯石英榴辉岩的发现  

THE DISCOVERY OF COESITE-BEARING ECLOGITES IN THE DABIE MOUNTAINS

作　　者：潘国强 荆延仁 夏木林 梁万通[2] 王小民[3] 刘忠光[3] 丸山茂德 毛河光[5] 

机构地区：[1]安徽省地质矿产局区域地质调查队 [2]长春地质学院地质系 [3]美国斯坦福大学地质系 [4]日本东京大学地球科学系 [5]美国华盛顿卡内基研究所地球物理实验室

出　　处：《地质论评》1990年第4期359-363,T001,共6页Geological Review

摘　　要：大别山区的榴辉岩可划分为四种类型,目前已在第Ⅲ类和第Ⅰ类中分别发现了柯石英及其假像。柯石英除鉴定其光学特征外,还经显微拉曼光谱证实。含柯石英榴辉岩的形成条件为T600°—710℃,P>2.8GPa,表明其形成于上地幔。大别山区含柯石英榴辉岩是目前世界上发现的少数几处非金伯利岩型高压变质岩之一。它的形成可能与三叠纪中朝板块与扬子板块间发生的陆内俯冲作用有关。Eclogites may be divided into four types in the Dabie Mountain. Coesite and its quartz-pseudomorph have been discovered in the eclogites of the third and first types. The coesite was confirmed by Micro-Raman spectroscopy, besides the determination of its opitical characteristics. It is biaxial and shows a higher relief than quartz and lower interference colors (grey of the first order). The site occurs mostly in garnets and omphancites as inclusions. The coesite-bearing eclogites were estimated to be formed at pressures greater than 2.84 GPa and temperatures of 600—710℃ according to geothermometrs and geobarometers. The authors suggest that these eclogites originated in the upper mantle. The coesite-bearing eclogites are non-kimberlite-type high-pressure metamorphic rocks discovered in rare localities in the world at present. Its formation might be related to the intracontinental subduction that occurred between the Sino-Korean plate and the Yangtze plate in the Triassic.

关 键 词：榴辉岩 柯石英 类型 

分 类 号：P588.3[天文地球—岩石学]