汶川地震对华北地区水平形变场影响及有关含义的讨论  

Influence of Wenchuan Earthquake on the Horizontal Deformation Field in North China and its Implications

作　　者：杨国华[1] 杨博[1] 张风霜[1] 韩月萍[1] 刘峡[1] 

机构地区：[1]中国地震局第一监测中心,天津300180

出　　处：《地震》2009年第1期77-84,共8页Earthquake

基　　金：国家科技支撑项目(2006BAC01B03-01-01);地震科学联合基金项目(A07066)

摘　　要：通过2008年华北地区的GPS监测资料处理,初步分析表明:①华北地区(山西断陷带以东地区)水平形变在汶川地震(MS8.0)临震前数个月及同震时段(震后数个月)内整体有序且与地震相关的差异变化不明显,基本上继承了上一时段(2004—2007年)的运动方式;②从震后偏离上一时段运动方式的偏离结果来看,汶川地震的影响主要体现在山西断陷带的南端,此外也发现华北地区似乎有微弱的动态变化,其东北地区存在某种程度的偏离背景变化,东南与西北地区略有加速的迹象。从信息显著性的角度来看,由于其信息的信噪比不高,所以有关讨论则更侧重于可能性或形变迹象。Primary analysis of the processed GPS monitoring data in 2008 in North China suggests： （1） The horizontal deformation field in North China （to the east of Shanxi fault zone） on the whole follows the movement mode of the last period （2004 2007）, and differential movement related to the earthquake is not obvious several months before the Wenchuan Ms8. 0 earthquake and in the coseismic period （several months after earthquake）; （2） Carefully observing the results deviating from the last period shows that the influence of Wenchuan Earthquake is mainly at the south part of Shanxi fault zone, and there appears a faintly dynamic movement in North China. In the northeast area there exists to some extent movement deviating from the background result, and the southeast and northwest regions have the evidence of accelerating. But from the point of information notability, the related discussion is mainly focused on possibility or evidence of deformation due to the low signal-to-noise ratio of the information.

关 键 词：水平形变 动态特征 汶川地震的影响 华北地区 

分 类 号：P315.7[天文地球—地震学]