【摘要】 榴辉岩是华中高压变质带的特征岩类之一。根据其共生的矿物组合可划分出四类榴辉岩:角闪(蓝闪)榴辉岩,蓝晶石榴辉岩、柯石英榴辉岩和石英榴辉岩。其中蓝闪榴辉岩主要分布于团麻断裂以西地区;柯石英榴辉岩均出露于团麻断裂以东地区。根据矿物对地质温压计和变质矿物组合估测,西部地段榴辉岩的形成条件为p=1.1～1.5GPa,t=540～600℃,中东部地段榴辉岩为p≥2.5GPa,t=700～800℃。 根据岩石组合、矿物组合和构造环境分析,绝大多数(如果不是全部的话)榴辉岩与围岩经历了相同的高压—超高压变质作用,是同一构造运动旋回中不同构造部位的变质产物。蓝闪榴辉岩和柯石英榴辉岩的地质环境和退变质作用特征具有重要的大地构造意义。更多还原

【Abstract】 The eclogites in central China,occurring as a belt more than 2000km long and 40 to 100km wide which are approximately parallel to the blueschist belt, run across Hubei,Anhui,Jiangsu and Shandong provinces.Geologically and geo-graphically,the eclogite belt can be divided into three parts by the Tuanshan-Macheng and Tancheng-Lujiang fault zones.The differences between western and middle-eastern parts are obvious and mineral compositions.Eclogite bodies,which are generally tabular in western part in Mid-Upper Proterozoic and lenticular and Archean, have a chemical exchang with their host rocks.The eclogites in central China are classified into four varieties according to their mineral assemblages,they are Na-amphibole(Glaucophane)eclogite,kyanite ec-logite,coesite eclogite and quartz eclogite.Each of the former three has regular geologic and retrogressive features.The eclogites are hosted by different rocks such as meta-basites,gneisses,marbles and ultramafic rocks.On the basis of petrological and geochemical studies,especially on the research of relict high pressure minerals in host rocks,the authors believe that most(if not all) eclogites are symmetamorphic products with their country rocks. Thus the evolution of glaucophane eclogite(540-600℃ ,1.1-1.5 GPa)and coesite eclogite (700-800℃,≥2.5 GPa)isof great importance to explain the tectonic evolution of the high pressure metamorphic belt in central China.更多还原