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《地震研究》[ISSN:1000-0666/CN:53-1062/P]

卷:

44

期数:

2021年04期

页码:

613-621

栏目:

出版日期:

2021-11-10

文章信息/Info

Title:

Vertical Deformation in the Northern Section of the North-South Seismic Belt before and after the Wenchuan M_S8.0 Earthquake Based on GPS Data

作者:

梁洪宝; 杨国华

(中国地震局第一监测中心,天津 300180)

Author(s):

LIANG Hongbao; YANG Guohua

(First Crust Monitoring and Application Center,China Earthquake Administration,Tianjin 300180,China)

关键词:

GPS;  汶川M_S8.0地震;  南北地震带北段;  垂向形变

Keywords:

Global Positioning System;  the Wenchuan M_S8.0 earthquake;  the Northern section of the North-South Seismic Belt;  vertical deformation

分类号:

P315.72

DOI:

-

摘要:

2008年汶川M_S8.0地震对南北地震带北段垂向变形产生了影响,对1999—2016年多期GPS观测数据进行精密解算,采用多面函数方法分别对研究区垂向运动进行周年运动剔除和空间滤波,获取了汶川地震前后垂向形变特征。结果表明:①以巴颜喀拉块体与华南块体交界带西侧为界,其西部自东向西呈指数函数衰减; 东部自西向东呈对数函数形式衰减,且东部衰减程度大于西部,两块体交界南北段垂向形变特征存在差异性,北段隆升速度和变化梯度均弱于南段; ②地震前后南北地震带北段垂向形变特征具有明显差异性,相对震前,震后大部分区域隆升速度加快,平均约为2 mm/a,局部区域加快程度较大,最大值达7 mm/a; ③垂向速度的差异性变化对地壳的垂向应变积累具有影响,最大正影响区域为巴颜喀拉块体与华南块体交界及其西侧区域,增大了约10×10^-8/a,约为震前的2倍,最大负影响区域为川滇块体北部局部区域,减小了约7×10^-8/a 。建议对巴颜喀拉块体与华南块体交界及其西侧区域和川滇块体北部局部区域强化跟踪分析。

Abstract:

In view of the influence of the 2008 Wenchuan M_S8.0 earthquake on the vertical deformation of the northern segment of the North-South Seismic Belt,we calculate with high precision the multi-period GPS observation data during 1999-2016,the features of vertical deformation before and after earthquake are obtained by using the method of polyhedral function to eliminate annual motion and spatial filtering respectively.The results show that:① In the west side of the junctions of the Bayan Har Block and the South China Block,the vertical deformation attenuates from the east to the west in the form of an exponential function,while in the west side the vertical deformation attenuates from the west to the east in the form of a logarithmic function,and the attenuation in the east is greater than in the west.The vertical-deformation characteristics in the north are different from the ones in the south of the two Blocks’ junctions.The uplift rate and the change gradient in the northern section are weaker than the ones in the southern section.② The vertical deformation of the Northern section of the North-South Seismic Belt before the Wenchuan earthquake was obviously different from the one after the earthquake.The uplift rate accelerates in most areas after the earthquake,with an average of about 2 mm/a and a maximum of 7 mm/a in the local area.The uplift rate of the local area decreases and the amplitude decreases within 2 mm/a.③ The variation of the vertical velocity has an effect on the vertical strain accumulation in the Crust.The largest positive influenced area is the junction of the Blocks and its western region,with increments about 10×10^-8/a and about 2 times of the ones relative to pre-earthquake.The largest negative influenced region is the northern part of the Sichuan-Yunnan Block,with a reduction about 7×10^-8/a.It is necessary to conduct an intensive GPS observation of the junction between the Bayan Har Block and the South China Block and its western region as well as the northern part of the Sichuan-Yunnan Block should be strengthened.

参考文献/References:

陈运泰.2008.汶川特大地震的震级和断层长度[J].科技导报,(10):26-27.
杜方,闻学泽,张培震,等.2009.2008年汶川8.0级地震前横跨龙门山断裂带的震间形变[J].地球物理学报,52(11):2729-2738.
黄媛,吴建平,张天中,等.2008.汶川8.0级大地震及其余震序列重定位研究[J].中国科学:地球科学,38(10):1242-1249.
江在森,方颖,武艳强,等.2009.汶川8.0级地震前区域地壳运动与变形动态过程[J].地球物理学报,52(2):505-518.
李强,游新兆,杨少敏,等.2012.中国大陆构造变形高精度大密度GPS监测——现今速度场[J].中国科学:地球科学,42(5):629-632.
牛之俊,马宗晋,陈鑫连,等.2002.中国地壳运动观测网络[J].大地测量与地球动力学,22(3):88-93.
滕吉文,白登海,杨辉,等.2008.2008汶川M_S8.0地震发生的深层过程和动力学响应[J].地球物理学报,51(5):1385-1402.
王东振,赵斌,余建胜,等.2021.流动GPS观测资料能否用于地壳垂直形变监测?——以中国大陆为例[J].大地测量与地球动力学,41(3):290-295.
王敏,沈正康,董大南.2005.非构造形变对GPS 连续站位置时间序列的影响和修正[J].地球物理学报,48(5):1045-1052.
武艳强,江在森,杨国华,等.2009.利用多面函数整体求解GPS应变场的方法及应用[J].武汉大学学报(信息科学版),34(9):1085-1089.
徐锡伟,闻学泽,叶建青,等.2008.汶川M_S8.0地震地表破裂带及其发震构造[J].地震地质,30(3):597-629.
杨少敏,兰启贵,聂兆生,等.2012.用多种数据构建2008年汶川特大地震同震位移场[J].地球物理学报,55(8):2575-2588.
占伟,李斐,朱爽,等.2016.应用GPS连续观测修正流动观测垂向速率的分析与实验[J].武汉大学学报(信息科学版),41(7):963-968.
朱守彪,石耀霖.2005.青藏高原地形扩展力以及下地壳对上地壳的拖曳力的遗传有限单元法反演[J].北京大学学报(自然科学版),41(2):225-234.
朱守彪,张培震.2009.2008年汶川M_S8.0地震发生过程的动力学机制研究[J].地球物理学报,52(2):418-427.
朱文耀,付养,李彦.2003.利用GPS高程导出的全球高程振荡运动及季节变化[J].中国科学:地球科学,33(5):470-481.
邹镇宇,江在森,武艳强,等.2015.基于GPS速度场变化结果研究汶川地震前后南北地震带地壳运动动态特征[J].地球物理学报,58(5):1597-1609.
Alexander L,Densmore,Michael A,et al.2007.Active tectonics of the Beichuan and Pengguan faults at the eastern margin of the Tibetan Plateau[J].Tectonics,26(4):1-17.
Brown L D,Reilinger R E.1980.Releveling Data in North America:Implications for Vertical Motions of Plate Interiors.Dynamics of Plate Interiors[M].American Geophysical Union(AGU):131-145.
B?hm J,Nill A,Tregoning P,et al.2006.The Global Mapping Function(GMF):A new empirical mapping function based on numerical weather model data[J].Geophysical Research Letters,25(33):L07304.
Chang L J,Flesch L M,Wang C Y,et al.2015.Vertical coherence of deformation in lithosphere in the eastern Himalayan syntaxis using GPS,Quaternary fault slip rates,and shear wave splitting data[J].Geophysical Research Letters,42(14):5813-5819.
Fu Y,Freymueller J T.2012.Seasonal and long-term vertical deformation in the Nepal Himalaya constrained by GPS and GRACE measurements[J].Journal of Geophysical Research,117(B3):B03407.
Hao M,Qin S L,Shen Z K,et al.2014.Present day crustal vertical movement inferred from precise leveling data in eastern margin of Tibetan Plateau[J].Tectonophysics,632(29):281-292.
Herring T A,King R W,McClusky S C.2010a.GAMIT Reference Manual.GPS Analysis at MIT version 10.4[M].Cambridge:Massachusetts Institute of technology.
Herring T A,King R W,McClusky S C.2010b.GLOBK Reference Manual.Global Kalman filter VLBI and GPS analysis program[M].Cambridge:Massachusetts Institute of Technology.
Liang H B,Zhan W,Li J W.2021.Vertical surface displacement of mainland China from GPS using the multisurface function method[J].Advances in Space Research,https://doi.org/10.1016/j.asr. 2021.02.024.
Liang S M,Gan W J,Shen Z K,et al.2013.Three-dimensional velocity field of present-day crustal motion of the Tibetan Plateau derived from GPS measurements[J].Journal of Geophysical Research Solid Earth,118(10):5722-5732.
Liu R L,Li J C,Fok H M,et al.2014.Earth surface deformation in the North China Plain detected by joint analysis of GRACE and GPS data[J].Sensors,14(10):19861-19876.
Liu S,Jiansi Y,Tian B F,et al.2016.Seismic anisotropy determined by shear-wave splitting beneath the eastern Tibetan Plateau[J].Pure and Applied Geophysics,173(2):439-445.
Lyard F,Lefevre F,Letellier T,et al.2006.Modelling the global ocean tides:Modern insights from FES2004[J].Journal of Geophysical Research Atmospheres,56(5):394-415.
Royden L H,Burchfiel B C,Hilst R D V D.2008.The geological evolution of Tibetan plateau[J].Science,321(5892):1054-1058.
Royden L H,Burchiel B C,King R W,et al.1997.Surface deformation and lower crustal flow in eastern Tibet[J].Science,276(5313):788-790.
Schmid R,Steigenberger P,Gendt G,et al.2007.Generation of a consistent absolute phase center correction model for GPS receiver and satellite antennas[J].Journal of Geodesy,81(12):781-798.
Tesmer V,Steigenberger P,Dam T V,et al.2011.Vertical deformations from homogeneously processed GRACE and global GPS long-term series[J].Journal of Geodesy,85(5):291-310.
Tregoning P,van Dam T.2005.Effects of atmospheric pressure loading and seven-parameter transformation on estimates of geodetic motion and station heights from space geodetic observations[J].Journal of Geophysical Research Solid Earth,110(B3):B03408.
Tregoning P,Watson C.2009.Atmospheric effects and spurious signals in GPS analyses[J].Journal of Geophysical Research:Solid Earth,114(B9):B09403.
Wang Q,Qiao X,Lan Q G,et al.2011.Rupture of deep faults in the 2008 Wenchuan earthquake and uplift of the Longmen Shan[J].Nature Geoscience,4(9):634-640.
Yang G H,Liu Z G,Feng S T,et al.2013.Simulation of land subsidence in North China based on campaign GPS data in a decade[C].Frontiers of Discontinuous Numerical Methods and Practical Simulations in Engineering and Disaster Prevention,513-517.

备注/Memo

备注/Memo:

收稿日期:2021-02-02
基金项目:国家自然科学基金项目(41974011)和国家重点研发计划课题(2018YFC1503606)联合资助.

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更新日期/Last Update: 2021-11-10