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分布于皖北和苏北徐淮地区的早侏罗世侵入杂岩体主要由二长闪长斑岩组成,其形成时代为191Ma.岩体中含有大量的榴辉岩类包体,主要由榴辉岩和石榴辉石岩组成,它们经历了榴辉岩相高压变质和角闪岩相退化变质两个阶段.包体榴辉岩中的石榴石以铁铝榴石为主;单斜辉石主要是绿辉石和普通辉石.矿物组合及温度和压力计算结果表明,该类包体榴辉岩相变质的温度和压力条件为大于1.2～1.5GPa和709～861℃;角闪岩相退化变质的温度和压力条件为0.70～1.03 GPa和666～738℃.该类高压捕虏体的发现不仅对了解华北陆台南缘深部陆壳的物质组成与结构具有重要意义,而且可能对认识大别-苏鲁超高压变质带的俯冲-碰撞-折返演化过程产生重要影响.
The Early Jurassic intrusive complex distributed in the northern part of Anhui Province and the Xuhuai area of northern Jiangsu mainly consists of two long-dioritic porphyries, forming at 191 Ma. There are a large number of eclogite inclusions in the rock mass, Eclogites and garnet pyroxenes, which experienced two stages of high pressure metamorphism of eclogite facies and degenerated metamorphism of amphibolite facies. The garnet in the enclave eclogite is dominated by almandine; monoclinic The results show that the temperature and pressure conditions of eclogite facies metamorphism are more than 1.2 ~ 1.5GPa and 709 ~ 861 ℃. The amphibolite facies The temperature and pressure conditions for degenerated metamorphism range from 0.70 to 1.03 GPa and from 666 to 738 ° C. The discovery of these high-pressure xenoliths is not only important for understanding the material composition and structure of the deep continental crust in the southern margin of the Lvtai, North China, The Subduction - Collision - Reentry Evolution Process of UHP Metamorphic Belts in Bie - Sulu Area has an Important Influence.