中条山早元古代变质岩石的PTt轨迹和构造演化

中条山早元古代变质岩石呈北东向分布，经历了中低级变质作用。本文在变质作用研究的基础上，结合地质构造和显微构造，利用近来发展的石榴石环带定量测量Ｐ－Ｔ轨迹的技术，建立了绛县群和中条群泥质岩石经历的ＰＴｔ轨迹。ＰＴｔ轨迹表明绛县群经历拉张作用，地壳发生抬升，产生绿片岩相变质；在中条第Ⅰ期运动中，地壳略有增厚或不变升温和抬升，产生低角闪岩相变质；而中条群岩石经历低绿片岩相埋深变质后，于中条第Ⅰ期运动中，

METAMORPHIC P-Tt PATHS AND TECTONIC EVOLUTION OF EARLY PROTEROZOIC ROCKS FROM THE ZHONGTIAO MOUNT AINS, SOUTHERN SHANXI

Early Proterozoic supracrustal rocks of the Zhongtiao Mountains consist of three groups-Jiangxian Group, Zhongtiao Group and Danshanshi Group, which range in tnetamorphic grade from greenschist to lower amphibolite facies.This discussion focuses on pelttic rocks in the Jiangxian Group and Zhongtian Group, from which information about the P-T paths of the tectonic evolution can be obtained.The P-T paths of the Jiangxian Group display slight temperature rise and pressure decline during D1 deformation and M1 metamorphism and slight pressure and temperature increases during D2 deformation and M2 metamorphism. The P-T paths of the Zhongtiao Group show temperature and pressure increases during D2 deformation and M2 metamorphism. There exist thermic metamorphism and retro-metamorphism during D3 deformation and M3 metamorphism.The rocks of the Jiangxian Group experienced uplift under the influence of the Jiangxian defomation and Zhongtiao deformation, and the rocks of the Zhongtiao Group experienced crustal thickening during the uplift and erosion of the crust.