数值模拟探讨青藏高原东部应力应变场及断裂活动性

发布时间：2018-05-31 20:20

本文选题：青藏高原东部 + 数值模拟　；参考：《地球学报》2017年03期

【摘要】：青藏高原东部是我国活动构造非常强烈的区域,现今的应力应变状态对活动构造研究有重要参考意义。本文依据地质资料和岩石力学性质构建相应的有限元数值模型,以GPS观测为边界约束,计算得到了青藏高原东部应力应变场,在此基础上探讨了主要断裂的活动特征。结果显示,距离印度板块和欧亚大陆板块碰撞带较近的青藏高原,汇聚速度、最大压应变率和最大压应力均较高,而随着远离碰撞带各个数值相应降低;在青藏高原东部,以喜马拉雅东构造结为旋转中心的一系列弧形断裂滑动速率相对较高,如玉树—鲜水河—小江断裂带,巴塘—金沙江断裂带,嘉黎断裂带等,这些走滑断裂带控制着青藏高原东南缘物质旋转挤出的特征,而其它断裂带滑动速率则相对较低,在块体内部则更低;结果同时表明应变速率分配高的断裂达到屈服的时间短,对应的地震复发周期短。
[Abstract]:The eastern Qinghai-Xizang Plateau is a very strong area of active tectonics in China. The present stress-strain state is of great significance for the study of active tectonics. Based on the geological data and the mechanical properties of rock, the corresponding finite element numerical model is constructed in this paper. The stress and strain field of the eastern Qinghai-Xizang Plateau is calculated with the GPS observation as the boundary constraint, and the active characteristics of the main faults are discussed. The results show that the convergence velocity, maximum compressive strain rate and maximum compressive stress are higher in the Qinghai-Tibet Plateau, which is close to the collision zone between the Indian plate and the Eurasian plate, but decreases with the distance from the collision zone, and in the eastern part of the Qinghai-Xizang Plateau, The slip rate of a series of arc-shaped faults, such as Yushu Xianshuihe-Xiaojiang fault zone, Batang-Jinshajiang fault zone, Jiali fault zone and so on, is relatively high with the Himalayan East structure as the center of rotation. These strike-slip fault zones control the characteristics of mass rotational extrusion in the southeastern margin of the Qinghai-Xizang Plateau, while the sliding rate of other fault zones is relatively low, and even lower in the block interior, the results also show that the yield time of the faults with high strain rate distribution is short. The corresponding earthquake recurrence period is short.
【作者单位】：中国地质科学院地质力学研究所国土资源部新构造运动与地质灾害重点实验室;
【基金】：中国地质调查局地质调查项目(编号:DD20160268;12120113038000) 国家自然科学基金(编号:41641039;41574090) 中国地质科学院基本科研业务费(编号:YYWF201720)联合资助~~
【分类号】：P315.2

【相似文献】