基于大地测量与地质数据约束的红河断裂带滑移速率和闭锁特征反演研究

项目名称： 基于大地测量与地质数据约束的红河断裂带滑移速率和闭锁特征反演研究

项目编号： No.41461087

项目类型： 地区科学基金项目

立项/批准年度： 2015

项目学科： 天文学、地球科学

项目作者： 李金平

作者单位： 云南师范大学

项目金额： 51万元

中文摘要： 红河断裂带是我国云南境内一条经历长期演化的大型断裂，构造活动具有显著的分段特征，其中，北段历史强震频繁，而中－南段鲜有地震发生。关于该断裂现今的实际活动强度和地震危险性状况，目前仍有较大的争议。本项目拟对红断裂带远近场GPS和InSAR联合观测获取高分辨率的形变矢量速度场，以创建的GPS、InSAR速度矢量和地质走滑速率约束的三维形变块体模型，采用最小二乘法，反演确定断裂带的闭锁深度、深部断裂面几何展布及三维运动速率等参数，分析震间形变及断层蠕动形变过程，研究断裂带的现今构造运动模式、应变积累程度、闭锁状况，确定断层活动与区域构造应变关系，评价潜在的地震危险性。从根本上回答现今的红河断裂活动微弱，是已丧失川滇块体西南边界的地位和作用，还是目前处于强闭锁状态，仍具有发生大震的可能性这一科学问题。

中文关键词： 全球定位系统；雷达遥感；地震；构造变形；反演

英文摘要： The Red River Fault (RRF) in Yunnan is a large-scale strike-slip fault system experienced long period evolution, and tectonic activity has significant segment features. The historical strong earthquakes on RRF ruptured frequently its northern section. However, the central and southern sections of the fault have not produced a great earthquake in historic times. Today there are still a large controversy about the recent strength of actual activities and seismic hazard situation on RRF. In this project, the high-resolution deformation velocity field near and far RRF have been obtained from the geodetic techniques of GPS and InSAR. A new combined-inversion 3D block models have been constructed that is constrained by the GPS velocities, InSAR velocities and the geology-based fault slip rates. Based on 3D block model and least squares method, the geometry and kinematic parameters such as locking depth, deep fracture surface geometry exhibition and recent three-dimensional movement rate were inversed. On this basis, to analyze interseismic deformation and fault creep deformation process, to study present tectonic deformation pattern, strain accumulation and locking status. The relations were determined between the fault active and regional tectonic strain. The potential earthquake hazard were estimated. The scientific issue was answered about 'tectonic activity is weak, has lost the status and role of the southwest boundary of the Sichuan-Yunnan block or currently in a strong lock state, still has the possibility of large earthquakes occurred on the central and southern sections of RRF', and to provide decision support for regional seismic hazard assessment.

英文关键词： GPS;Radar Remote Sensing;Earthquake;Tectonic Deformation;Inversion