内蒙古色尔腾山地区花岗绿岩带糜棱岩变形变质过程探讨

采用不同研究方法分析和解读岩石和矿物的显微构造特征，能再造结晶基底岩石复杂的变形和变质演化过程和条件。通过对色尔腾山地区花岗绿岩带中韧性剪切带的糜棱岩显微构造、石英组构、矿物化学等综合分析，发现该区糜棱岩在经历了低角闪岩相区域变质及绿帘角闪岩相退变质变形之后，发生了不均匀进变质重结晶作用及中低绿片岩相退变质变形等几个演化阶段。由不同阶段温压条件所限定的p-T演化轨迹为一个在早期顺时针的基础上叠加了一个晚期逆时针环的复杂图像。

The deformation and metamorphic processes of mylonites in the granite-greenstone belt of Seerteng area, Inner Mongolia

Reconstruction of deformation and metamorphic processes and conditions can be carried out by studying micro-features of rock and minerals. This paper has investigated the microstructures, quartz fabrics, and mineral chemistry of mylonites from the ductile shear zone of the granite-greenstone belt in Seerteng area, Inner Mongolia. Synthetic analyses reveal that the mylonites underwent four evolutionary processes of deformation and metamorphism, such as lower-amphibolite facies regional metamorphism, retrograde epidote-amphibolite facies metamorphism and deformation, progressive recrystallization and retrograde greenschist facies metamorphism and deformation. The temperature and pressure combination of four metamorphic stages defines a clockwise p-T path, with the superimposition of a later anticlockwise p-T path.