[关键词]
[摘要]
利用2013~2017年3期GPS观测资料,获得精河6.6级地震前震中附近区域水平运动速率、主应变率、面膨胀率及最大剪应变率,并结合区域构造背景分析该区域变形动态特征。结果表明:震前震中附近区域速度场速率逐渐增大,发震断裂两盘构造运动速率不均,震中附近区域GPS测点的速率和运动方向存在差异,反应了地壳应变能量积累。震中区域主压应变率变化反映出应力调整过程,沿断层走向的张压转换的形变高梯度带、最大剪应变梯度带可为地震预测提供参考。
[Key word]
[Abstract]
Using an examination of three stages of Global Positioning System(GPS)observation dating from 2013 to 2017,we obtained the horizontal movement velocity,principal strain rate,surface expansion rate,and maximum shear strain rate around the epicenter area before the Jinghe MS6.6 earthquake. Combined with regional tectonic background analysis of the dynamic features of regional deformation,we find the results that in the area near the Jinghe earthquake foreshock velocity anomaly area,the rate gradually increases the rate changes unevenly,and the crustal strain accumulates. The direction change of the velocity field in the epicentral region promotes the occurrence of the earthquake. The change of the main pressure strain rate reflects the process of stress adjustment. The deformation high gradient belt and the maximum shear strain gradient belt are helpful for earthquake prediction.
[中图分类号]
P315
[基金项目]
中国地震局地震科技星火计划项目(XH17044)、新疆维吾尔自治区自然科学基金项目(2016D01A062)、中国科学院战略性先导科技专项(XDB18000000)共同资助