2011年日本Mw 9.0级地震的GPS响应研究  

GPS responses to the 2011 Mw 9.0 earthquake in Japan

作　　者：刘焱雄[1,2] 范士杰[1,2,3] 乔方利[1] 周兴华[1] 张健[1] 

机构地区：[1]国家海洋局第一海洋研究所,山东青岛266061 [2]武汉大学测绘学院,湖北武汉430079 [3]中国石油大学(华东)地球科学与技术学院,山东青岛266555

出　　处：《海洋学报》2012年第6期59-65,共7页

基　　金：国家"863"计划(2009AA12Z127);国家海洋局GNSS业务运行项目

摘　　要：2011年3月11日日本宫城县以东太平洋海域发生Mw 9.0级特大地震,造成了地表的严重错位并引发海啸。文中利用位于日本及周边国家的IGS站和国家海洋局GPS业务站观测数据,采用作者研制的精密单点定位(PPP)软件UniP,对此次地震的GPS数据响应进行了研究。结果表明:(1)GPS观测数据能清晰、连续地记录震时地表形变的过程,我国CHAN,NCST等站点水平方向的震时最大位移在10cm以内,高程方向的震时最大位移在15cm以内,且形变以可恢复性的弹性形变为主。(2)我国距震中较远,受此次日本地震的影响较小,且大部分站点是在东坐标方向出现不同程度的震后永久性位移。其中CHAN站点的震后位移最为明显,东向形变量为(1.8±0.11)cm;NCST、NLHT站点次之,东向形变量分别为(1.1±0.26)cm和(1.0±0.18)cm。(3)地震波传输到国家海洋局GPS业务站NCST、NLHT等的时间约为10min,比海啸在深海的传播速度快约14倍,可为海啸预警提供所需的时间差。这些结果显示出GPS能够为地震监测和动力学特征研究提供有价值的基础资料,也表明中国沿海GPS业务观测系统在海底地震监测、海啸预警服务中的应用潜力。A massive Mw 9.0 earthquake occurred on 11 March 2011, off the Pacific coast of the east of Miyagi, Japan. The earthquake caused severe surface dislocations and launched a tsunami. In this paper, our developed software UniP, based on the precise point positioning mode, is used to extract the co-seismic and post-seismic surface movement information from IGS data and Chinese coastal GPS data. The results show： （1） The co-seismic surface deformation processes are clearly recorded by the GPS kinematic positio- ning results, and these elastic deformation on CHAN and NCST sites is up to 15 cm. （2） The massive earthquake did not cause obvious permanent position shift of GPS sites in China, because of distant range. The maximum eastward shift on CHAN is（ 1.8±0.11）cm. （3） The travel time is almost 10 minutes for seismic wave to NCST and NLHT site. The propagation velocity of seismic wave is about 14 times faster than that of tsunami. So the arrival time difference may be enough for the tsunami prediction. These re- sults reveal that GPS technology can provide valuable basic data for earthquake monitoring and dynamic characteristics. It further demonstrates the application potential of Chinese Coastal GPS monitoring system in seaquake monitoring and tsunami warning services.

关 键 词：GPS 地震 精密单点定位 地表形变 海啸预警 

分 类 号：P731.235[天文地球—海洋科学]