赣中变质岩带变质作用PTt轨迹演化及其地质意义  

P-T-t PATHS OF METAMORPHIC ROCKS BELT IN CENTRAL JIANGXI PROVINCE AND THEIR IMPLICATIONS FOR EVOLUTION OF METAMORPHIC ENVIRONMENT, TECTONISM AND MIGMATISM

作　　者：胡恭任[1] 刘丛强[1] 章邦桐[2] 

机构地区：[1]中国科学院地球化学研究所 [2]南京大学内生金属矿床成矿机制研究国家重点实验室,江苏南京210093

出　　处：《大地构造与成矿学》2003年第2期176-183,共8页Geotectonica et Metallogenia

基　　金：国家杰出青年基金(49625304);南京大学内生金属矿床成矿机制研究国家重点实验室开放基金;华侨大学博士科研起动资金联合资助.

摘　　要：赣中变质岩带十字石榴云母片岩中石榴石成分环带是连续反应的结果,微区成分变化规律明显。本文根据该岩石的石榴石环带成分定量计算了变质作用P-T轨迹。P-T轨迹样式表明,赣中变质岩带的变质作用可以分两大期:第一期发生在大陆碰撞带环境中,变质作用的温度压力演化受均匀地壳增厚及隆起侵蚀过程控制;第二期发生在活动大陆边缘环境,变质作用温压条件与地壳回返上升,高温热流上涌有关。The zoned garnets of the metapelites from metamorphic rocks belt in central Jiangxi Province can all be attributed to the continuous reactions. The micro district composition variation in garnet has an obvious regularity. According to the garnet zoning, the patterns of the P T paths by quanitative calculation show that there have been two important metamorphic events occuring in the past. The first metamorphic event takes place in the tectonic environment of the continental collision zone. The geological factors that control the pressure and temperature conditions are the processes of uniform crustal thickening and uplift. The second event occurs in the active continental margin tectonic setting. The P/T condition is controlled by the heat flow rising from the deep crust.

关 键 词：变质岩 变质作用 P-T轨迹 大陆碰撞带 铀矿床 成矿作用 活动大陆边缘 

分 类 号：P619.14[天文地球—矿床学] P588.3[天文地球—地质学]