Fabric and Deformation of Omphacite in Dabie Ultra-high-pressure Ecologites  

作　　者：JIAO Shuqiang JIN Zhenmin JIN Shuyan TAN Zishan 

机构地区：[1] Department of Environmental and Resource Engineering, Fuzhou University, Fujian 350002 [2] Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074

出　　处：《Acta Geologica Sinica(English Edition)》1999年第4期411-417,共7页地质学报（英文版）

摘　　要：The rheological characters of omphacites in Dabie ultra-high-pressure eclogite have been studied in terms of fabric, dislocation and micro-structures. 1. The eclogite has undergone high-temperature deformation, thus forming omphacite lattice preferred orientation. In addition to creep dislocation, the omphacite ductile deformation may have other mechanisms, such as diffusion creep and grain boundary migration. 2. The main-phase deformation of eclogite is coaxial, but asymmetry strain also exists due to strain partitioning in the Dabie orogenic belt. 3. The twin measured by the universal stage is (100), indicating that omphacite high-T deformation was superimposed by low-T deformation. 4. Subgrain structure is common in omphacite, but the deformation features of the omphacites in the Shuanghe area and Bixiling area are different, the latter being dominated by dynamic recrystallization. 5. The Flinn plots show that the strain of omphacite belongs to the constriction ellipsoid and stretching strain, which is similar to the result of the omphacite fabric analysis.The rheological characters of omphacites in Dabie ultra-high-pressure eclogite have been studied in terms of fabric, dislocation and micro-structures. 1. The eclogite has undergone high-temperature deformation, thus forming omphacite lattice preferred orientation. In addition to creep dislocation, the omphacite ductile deformation may have other mechanisms, such as diffusion creep and grain boundary migration. 2. The main-phase deformation of eclogite is coaxial, but asymmetry strain also exists due to strain partitioning in the Dabie orogenic belt. 3. The twin measured by the universal stage is (100), indicating that omphacite high-T deformation was superimposed by low-T deformation. 4. Subgrain structure is common in omphacite, but the deformation features of the omphacites in the Shuanghe area and Bixiling area are different, the latter being dominated by dynamic recrystallization. 5. The Flinn plots show that the strain of omphacite belongs to the constriction ellipsoid and stretching strain, which is similar to the result of the omphacite fabric analysis.

关 键 词：OMPHACITE FABRIC ultra-high-pressure eclogite RHEOLOGY 

分 类 号：P588.125[天文地球—岩石学]