关键词: 剪切带, 斑晶, 塑性大变形, 计算机模拟, 太行山

Abstract: Numerical modeling for porphroblast's rotation and deformation of augen fabrics in ductile shear zones is done by a large plastic deformation programm based on detailed investigation to three ductile shear zones, Taihangshan Mountains. Some results acquired by computer calculation show that the rigid garnet pophyroblasts can rotate as their matrix flow, and the rotational degree depends on the shear force, ratio of poephroblasts to matrix and the locations of porphyroblasts in the model. Formation of augen fabrics is decided by the ductile deference between the porphyroblast and matrix in deformation rock. Plastic strain first starts from ambient of the porphyroblast, and then develops to rims of porphyroblast and gradually transfers to the centers of porphyroblasts. The brittle remains in the central parts of porphyroblasts come to be decreased through the plastic deformation development, which is accordance with the banding of intensity in many mylonitization zones on wild occurrences and observation in the fabrics of mylonitization rocks under microscope.

Key words: Taihang Mountains, Shear zones, porphyroblast, large plastic deformation, numerical modeling