玉树M_S7.1地震同震效应模拟与绝对重力检验
|
摘要
利用玉树震后地质调查获取的地表破裂位移,参考余震精定位结论以及地震波和InSAR反演结果,构建了玉树MS7.1地震发震断层模型。基于弹性-粘弹分层介质模型中平面矩形位错理论,考虑介质自重的影响,模拟了玉树地震同震形变和重力变化。图像显示,玉树绝对重力点刚好位于同震重力变化极值附近,变化量达到25.02×10-8m·s-2。通过对震前重力变化以及对两台FG-5绝对重力仪的一致性进行讨论,认为实测玉树台27.2×10-8m·s-2为同震重力变化,这与基于位错理论的同震模拟结果一致,是对位错理论近场变化的1次很好的验证。
Using the conclusion of aftershocks relocation, inversion on seismic wave and InSAR results, and surface rupture displacement obtained by geological survey after the earthquake, this paper constructs a faults model of Yushu MS7.1 earthquake. Based on rectangular dislocation theory in elastic-viscoelastic layering medium, we have simulated the co-seismic deformation and gravity change with gravitational effect considered. The pictures show that the absolute gravity measuring point is beside the extremum of coseismic gravity change, and the numerical value reach to 25.02×10-8m·s-2. After a discussion about the gravity changes before the earthquake and the coherence consistency between two FG-5 absolute gravimeters, we think that the measured value 27.2×10-8m·s-2 at Yushu station is coseismic gravity change. It's coincident with the simulation results based on dislocation theory. So it's good inspection to the near-field changes on dislocation theory.
Using the conclusion of aftershocks relocation, inversion on seismic wave and InSAR results, and surface rupture displacement obtained by geological survey after the earthquake, this paper constructs a faults model of Yushu MS7.1 earthquake. Based on rectangular dislocation theory in elastic-viscoelastic layering medium, we have simulated the co-seismic deformation and gravity change with gravitational effect considered. The pictures show that the absolute gravity measuring point is beside the extremum of coseismic gravity change, and the numerical value reach to 25.02×10-8m·s-2. After a discussion about the gravity changes before the earthquake and the coherence consistency between two FG-5 absolute gravimeters, we think that the measured value 27.2×10-8m·s-2 at Yushu station is coseismic gravity change. It's coincident with the simulation results based on dislocation theory. So it's good inspection to the near-field changes on dislocation theory.
引文
①徐锡伟,2011,青海玉树7.1级地震科学考察(地震地质)分队验收研究报告
陈立春、王虎、冉永康等,2010,玉树MS7.1级地震地表破裂与历史大地震,科学通报,55(13),1200～1205。
李瑞浩、黄建梁、李辉等,1997,唐山地震前后区域重力场变化机制,地震学报,19(4),399～407。
刘巧霞、杨卓欣、莘海亮等,2012,玉树MS7.1级地震部分余震重新定位及发震构造分析,地球物理学报,55(1),146～154。
申重阳、李辉、谈洪波,2008,汶川8.0级地震同震重力与形变效应模拟,大地测量与地球动力学,28(5),6～12。
孙鑫喆、徐锡伟、陈立春等,2012,2010年玉树地震地表破裂带典型破裂样式及其构造意义,地球物理学报,55(1),155～170。
谈洪波、申重阳、李辉,2008,断层位错引起的地表重力变化特征研究,大地测量与地球动力学,29(4),54～62。
谈洪波、申重阳、李辉等,2009a,断层位错引起的地表形变特征,大地测量与地球动力学,29(3),42～49。
谈洪波、申重阳、李辉等,2009b,汶川大地震震后重力变化和形变的黏弹分层模拟,地震学报,31(3),491～505。
谭凯、李杰、王琪,2007,大地测量约束下的阿尔泰岩石圈流变结构,地球物理学报,50(6),1713～1718。
王继、陈立春、田勤俭等,2010,玉树7.1级地震断层地表破裂带应急科考,中国地震,26(4),464～467。
王勇、张为民、詹金刚等,2004,重复绝对重力测量观测的滇西地区和拉萨点的重力变化及其意义,地球物理学报,47(1),95～100。
邢乐林、李辉、何志堂等,2008,成都基准台绝对重力复测结果分析,大地测量与地球动力学,28(6),38～42。
张勇、许力生、陈运泰,2010,2010年青海玉树地震震源过程,中国科学:地球科学,40(7),819～821。
周慧芳、张景发、胡乐银等,2011,青海玉树地震的InSAR数据同震形变场模拟与参数反演分析,地球信息科学学报,13(3),418～423。
Imanishi Y,Sato T,Higashi T,et al,2004,A network of superconducting gravimeters detects submicrogal coseismic gravitychanges,Science,306,476～478.
Tanaka Y,Okubo S,Machida M,et al,2001,First detection of absolute gravity change caused by earthquake,Geophys ResLett,28(15),2979～2981.
Wang R J,Francisco L M,Frank R,2006,PSGRN/PSCMP-a new code for caluclation co-and post-seismic deformation,geoidand gravity changes based on the viscoelastic-gravitational dislocation theory,Computers and Geosciences,32,527～541.
Xing L L,Li H,Li J C,et al,2009,Comparison of absolute gravity measurements obtained with FG5/232and FG5/214instruments,Geo-spatial Information Science,12(4),307～310.
陈立春、王虎、冉永康等,2010,玉树MS7.1级地震地表破裂与历史大地震,科学通报,55(13),1200～1205。
李瑞浩、黄建梁、李辉等,1997,唐山地震前后区域重力场变化机制,地震学报,19(4),399～407。
刘巧霞、杨卓欣、莘海亮等,2012,玉树MS7.1级地震部分余震重新定位及发震构造分析,地球物理学报,55(1),146～154。
申重阳、李辉、谈洪波,2008,汶川8.0级地震同震重力与形变效应模拟,大地测量与地球动力学,28(5),6～12。
孙鑫喆、徐锡伟、陈立春等,2012,2010年玉树地震地表破裂带典型破裂样式及其构造意义,地球物理学报,55(1),155～170。
谈洪波、申重阳、李辉,2008,断层位错引起的地表重力变化特征研究,大地测量与地球动力学,29(4),54～62。
谈洪波、申重阳、李辉等,2009a,断层位错引起的地表形变特征,大地测量与地球动力学,29(3),42～49。
谈洪波、申重阳、李辉等,2009b,汶川大地震震后重力变化和形变的黏弹分层模拟,地震学报,31(3),491～505。
谭凯、李杰、王琪,2007,大地测量约束下的阿尔泰岩石圈流变结构,地球物理学报,50(6),1713～1718。
王继、陈立春、田勤俭等,2010,玉树7.1级地震断层地表破裂带应急科考,中国地震,26(4),464～467。
王勇、张为民、詹金刚等,2004,重复绝对重力测量观测的滇西地区和拉萨点的重力变化及其意义,地球物理学报,47(1),95～100。
邢乐林、李辉、何志堂等,2008,成都基准台绝对重力复测结果分析,大地测量与地球动力学,28(6),38～42。
张勇、许力生、陈运泰,2010,2010年青海玉树地震震源过程,中国科学:地球科学,40(7),819～821。
周慧芳、张景发、胡乐银等,2011,青海玉树地震的InSAR数据同震形变场模拟与参数反演分析,地球信息科学学报,13(3),418～423。
Imanishi Y,Sato T,Higashi T,et al,2004,A network of superconducting gravimeters detects submicrogal coseismic gravitychanges,Science,306,476～478.
Tanaka Y,Okubo S,Machida M,et al,2001,First detection of absolute gravity change caused by earthquake,Geophys ResLett,28(15),2979～2981.
Wang R J,Francisco L M,Frank R,2006,PSGRN/PSCMP-a new code for caluclation co-and post-seismic deformation,geoidand gravity changes based on the viscoelastic-gravitational dislocation theory,Computers and Geosciences,32,527～541.
Xing L L,Li H,Li J C,et al,2009,Comparison of absolute gravity measurements obtained with FG5/232and FG5/214instruments,Geo-spatial Information Science,12(4),307～310.
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心