摘要
青藏高原山地系统地壳巨厚 ,约为正常地壳厚度的两倍 ,由于第四纪以来高原的急剧隆升而成为全球构造研究的热点。根据山地系统岩石圈运动的主要因素—构造带和断裂带 ,本文将青藏高原山地系统的地壳演变简化成一个平面问题和一个典型剖面问题的力学模型 ,应用变形体模拟构造带 ,采用摩擦模型模拟断裂带 ,并根据周边位移情况给出边界条件。应用ABAQUS有限元分析软件和位移加载 ,变成了青藏高原山地系统岩石圈应力—位移场的数值模拟分析 ,给出了应力和位移的分布规律。结果与青藏高原震源机制解P轴方位及地应力测量主应力方位吻合较好 。
Tibet plateau in mountain system is becoming one of the focuses of global technique research, because of its marvelous thick, which is twice of the normal thickness of Mountain System in lithosphere, and its rapid raise from the Forth Epoch. By using a finite element analysis software ABAQUS, the numeric analysis has been carried out and presented in this paper for the lithosphere stress field. It is the first time to use the displacement loading in the simulation of Tibet Plateau. During the analysis, the deformed elements are used to simulate the structure band, and friction mechanism is used to model the fracture band. The boundary conditions are given according to the boundary displacements around the Plateau. The stress and displacement distributions are obtained for the geological evolution of the plateau, which are consistent with P axial orientations of the seismic origin mechanism and the measured principle stress orientations. The analysis is also given for the dynamic lithosphere evolution of Mountain System in Tibet Plateau.
出处
《山地学报》
CSCD
2001年第4期289-298,共10页
Mountain Research
基金
中国博士后科学基金一等资助
