Seismogenic structure of Yongqing MS4.3 and Langfang MS3.0 earthquakes
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摘要: 基于首都圈数字地震台网的宽频带资料,首先采用CAP方法确定了永清MS4.3地震和廊坊MS3.0地震的震源机制解:永清地震节面Ⅰ的走向、倾角和滑动角分别为52°,62°和−140°,节面Ⅱ的走向、倾角和滑动角分别为300°,55°和−35°;廊坊地震节面I的走向、倾角和滑动角分别为48°,57°和−147°,节面Ⅱ的走向、倾角和滑动角分别为299°,63°和−38°。两次地震的震源机制解较为一致,推测它们可能具有相同的发震断层。利用近震转换波获得两次地震的震源深度,分别为19 km和13 km。利用双差法对两次地震的主余震进行重新定位,结果显示:两个地震序列的震中均呈NE向分布,余震震源深度均浅于主震震源深度,震源深度分别集中在17—20 km和12—13 km范围内,两个序列的短轴剖面揭示了震源分布均呈现倾向SE,倾角陡立的特点。将地震序列的分布与震源机制解的结果进行对比,认为两个序列的水平展布方向与其对应的主震震源机制解中节面Ⅰ的走向比较接近,深度分布的高倾角特征也与节面Ⅰ比较相似,因此认为发震断层面均为节面Ⅰ。通过将震源机制解中节面Ⅰ的参数和地震序列的分布与区域活动断层的产状性质进行比较,取得了一些关于发震构造和地震成因的重要认识:① 永清MS4.3地震和廊坊MS3.0地震的发震构造不是上地壳的先存正断裂−河西务断裂,不排除与中下地壳的新生构造或深大断裂有关;② 永清、廊坊地震发生在13—19 km深度上,结合地壳结构、断裂构造以及区域流变结构等资料,推测该深度范围可能是廊固凹陷的壳内脆性−韧性转换区域,是地震孕育和发生的有利构造部位。Abstract: On February 12, 2018 and February 3, 2019, the MS4.3 and MS3.0 earthquakes occurred in Yongqing county and Langfang city, Hebei Province, and the two epicenters were less than 10 km apart. In order to study the seismogenic structure of these two earthquakes, based on the wide-band data of the digital seismic network of the Capital Circle, the focal mechanism solutions of the two earthquakes were determined by the CAP method first. For the Yongqing earthquake, the strikes, dip angle and rake angle of nodal plane I are 52°, 62° and −140° separately; and the strikes, dip angle and rake angle of nodal plane II are 300°, 55° and −35° separately; For the Langfang earthquake, the strike, tilt angle and slide angle of nodal plane I are 48°, 57° and −147° separately, and the direction, inclination and sliding angle of joint II are 299°, 63° and −38° separately. The focal mechanism solutions of the two earthquakes are relatively consistent, hence it is speculated that they may have the same seismogenic fault. The source depths of the two earthquakes obtained by converted waves of near earthquakes are 19 km and 13 km, respectively. The double-difference method was used to relocate the main and aftershocks of the two earthquakes. The results show that the epicenters of the two earthquake sequences are NE-directed, and the aftershocks all occur above the main shock. The focal depths are respectively concentrated in the range of 17−20 km and 12−13 km. Besides, the short-axis profiles of the two sequences reveal that the source distributions are characterized by SE tendency and steep dip angle. By comparing the seismic sequence distribution with the focal mechanism solutions, it found that the horizontal distribution direction of thesequences ars closer to the trend of the joint surface I in the focal mechanism solutions of the two earthquakes, and the high dip angle characteristics of the depth distribution are also similar to the joint surface I. Therefore, the seismogenic fault plane is considered to be nodal plane I. By comparing the parameters of nodal I from the focal mechanism solutions, the distribution of seismic sequences and the attitude properties of regional active faults, some important knowledge about the seismogenic structure and the origin of earthquakes was obtained: ① The seismogenic structure of the Yongqing MS4.3 earthquake and the langfang MS3.0 earthquake are not the pre-existing normal fault of the upper crust−the Hexiwu fault, and it may relate to the nascent structure of the middle and lower crust or deep faults. ② The Yongqing and Langfang earthquakes occurred at a depth of 13−19 km. Synthesize the crustal structure, fault structure and regional rheological structure, it is speculated that this depth range may be the intracrustal brittle-ductile transition area in the Langgu depression, which is favorable structural part for earthquake preparation and occurrence.
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图 1 首都圈地震台站和永清MS4.3地震、廊坊MS3.0地震震中位置及断裂分布图
(a) 地震台站与地震震中位置分布图;(b) 永清、廊坊地震震中附近断裂分布
Figure 1. Distribution map of Capital Circle stations and epicenters of Yongqing MS4.3 earthquake and Langfang MS3.0 earthquake along with the faluts around
(a) Distribution of seismic stations and epicenters;(b) Faults distribution near the epicenters of Yongqing and Langfang earthquakes
图 3 永清MS4.3地震震源机制解及理论波形(红色)与观测波形(黑色)对比图
波形左侧数据依次为台站名、震中距 (单位:km)及方位角 (单位:°),波形下方的数字表示理论波形相对于实际波形的移动时间 (单位:s) 及二者的相关系数
Figure 3. Focal mechanism solutions and comparison diagram of the synthetic (red) and observed (black) waveforms for the Yongqing MS4.3 earthquake
The station names are given on the left,and the numbers on right and below are epicentral distances (unit in km) and azimuths (unit in degree). Number below the traces are the time shift (unit in second) of the synthetic waveforms relative to the observed ones as well as the corresponding cross-correlation
图 7 永清MS4.3地震序列和廊坊MS3.0地震序列双差精定位结果
(a) 两次地震序列的震中分布图; (b) BB′ 剖面震源深度分布图; (c) A′ A剖面震源深度分布图; (d) C′ C剖面震源深度分布图
Figure 7. Relocated results of Yongqing MS4.3 and Langfang MS3.0 earthquake sequences by HYPODD
(a) Epicenter distributions map of earthquake sequences;(b) Focal depth distribution of BB′ profile; (c) Focal depth distribution of A′ A profile;(d) Focal depth distribution of C′ C profile
表 1 基于不同地壳模型的永清MS4.3地震和廊坊MS3.0地震震源机制解对比
Table 1 Comparison of the focal mechanism solutions of Yongqing MS4.3 earthquake and Langfang MS3.0 earthquake based on different crust models
地震 节面Ⅰ 节面Ⅱ T 轴 B 轴 P 轴 深度
/km速度模型 走向
/°倾角
/°滑动角
/°走向
/°倾角
/°滑动角
/°方位角
/°仰角
/°方位角
/°仰角
/°方位角
/°仰角
/°永清MS4.3 52 62 −140 300 55 −35 175 4 81 43 269 47 19 本文 53 62 −142 303 57 −34 177 3 84 44 268 46 19 谢祖军 (2013) 廊坊MS3.0 48 57 −147 299 63 −38 354 4 88 45 261 45 14 本文 49 56 −142 295 59 −41 353 2 85 41 261 49 14 黄建平等 (2009) -
常健,邱楠生,赵贤正,许威,徐秋晨,金凤鸣,韩春元,马学峰,董雄英,梁小娟. 2016. 渤海湾盆地冀中坳陷现今地热特征[J]. 地球物理学报,59(3):1003–1016. doi: 10.6038/cjg20160322 Chang J,Qiu N S,Zhao X Z,Xu W,Xu Q C,Jin F M,Han C Y,Ma X F,Dong X Y,Liang X J. 2016. Present-day geothermal regime of the Jizhong depression in Bohai Bay basin,East China[J]. Chinese Journal of Geophysics,59(3):1003–1016 (in Chinese).
丁志峰,曾融生. 1990. 京津唐地区震源深度分布初探[J]. 地震学报,12(2):242–247. Ding Z F,Zeng R S. 1990. A preliminary study of focal depth distribution in the Beijing-Tianjin-Tangshan area[J]. Acta Seismologica Sinica,12(2):242–247 (in Chinese).
董一兵,倪四道,李志伟,孟立朋,朱音杰,刘新. 2018. 基于近震转换波的沉积层地区震源深度测定方法[J]. 地球物理学报,61(1):199–215. doi: 10.6038/cjg2018L0184 Dong Y B,Ni S D,Li Z W,Meng L P,Zhu Y J,Liu X. 2018. Resolving focal depth based on local converted seismic waves in sedimentary regions[J]. Chinese Journal of Geophysics,61(1):199–215 (in Chinese).
段永红,王夫运,张先康,林吉焱,刘志,刘保峰,杨卓欣,郭文斌,魏运浩. 2016. 华北克拉通中东部地壳三维速度结构模型(HBCrust1.0)[J]. 中国科学:地球科学,46(6):845–856. Duan Y H,Wang F Y,Zhang X K,Lin J Y,Liu Z,Liu B F,Yang Z X,Guo W B,Wei Y H. 2016. Three dimensional crustal velocity structure model of the middle-eastern North China Craton (HBCrust1.0)[J]. Scientia Sinica Terrae,46(6):845–856 (in Chinese).
桂宝玲. 2011. 伸展盆地构造几何学、运动学: 以渤海湾盆地廊固凹陷为例[D]. 北京: 中国地质大学(北京): 67–68. Gui B L. 2011. The Structural Geometry and Kinemics of Extensional Basin: An Example from Langfang−Gu′an Depression Bohai Gulf Basin[D]. Beijing: China University of Geosciences (Beijing): 67–68 (in Chinese).
国家地震局 《深部物探成果》 编写组. 1986. 中国地壳上地幔地球物理探测成果[M]. 北京: 地震出版社: 112–113. Editional Group for Deep Geophysical Exploration Results, State Seismological Bureau. 1986. Geophysical Exploration Results of Mantle Upper Mantle in China[M]. Beijing: Seismological Press: 112–113 (in Chinese).
黄建平,倪四道,傅容珊,钮凤林,邵志刚,郑勇. 2009. 综合近震及远震波形反演2006文安地震(MW5.1)的震源机制解[J]. 地球物理学报,52(1):120–130. Huang J P,Ni S D,Fu R S,Niu F L,Shao Z G,Zheng Y. 2009. Source mechanism of the 2006 MW5.1 Wen’an earthquake determined from a joint inversion of local and teleseismic broadband waveform data[J]. Chinese Journal of Geophysics,52(1):120–130 (in Chinese). doi: 10.1002/cjg2.1333
嘉世旭,张先康. 2005. 华北不同构造块体地壳结构及其对比研究[J]. 地球物理学报,48(3):611–620. doi: 10.3321/j.issn:0001-5733.2005.03.019 Jia S X,Zhang X K. 2005. Crustal structure and comparison of different tectonic blocks in North China[J]. Chinese Journal of Geophysics,48(3):611–620 (in Chinese). doi: 10.1002/cjg2.694
嘉世旭,张成科,赵金仁,方盛明,刘志,赵俊猛. 2009. 华北东北部裂陷盆地与燕山隆起地壳结构[J]. 地球物理学报,52(1):99–110. Jia S X,Zhang C K,Zhao J R,Fang S M,Liu Z,Zhao J M. 2009. Crustal structure of the rift-depression basin and Yanshan uplift in the northeast part of North China[J]. Chinese Journal of Geophysics,52(1):99–110 (in Chinese).
姜文亮,张景发. 2012. 首都圈地区精细地壳结构-基于重力场的反演[J]. 地球物理学报,55(5):1646–1661. doi: 10.6038/j.issn.0001-5733.2012.05.022 Jiang W L,Zhang J F. 2012. Fine crustal structure beneath Capital area of China derived from gravity[J]. Chinese Journal of Geophysics,55(5):1646–1661 (in Chinese).
李德生. 1980. 渤海湾含油气盆地的地质和构造特征[J]. 石油学报,1(1):6–20. doi: 10.7623/syxb198001002 Li D S. 1980. Geology and structural characteristics of Bohai Bay,China[J]. Acta Petrolei Sinica,1(1):6–20 (in Chinese).
李赫,董一兵,王熠熙,彭研枫,刘双庆,吴博洋. 2020. 廊固凹陷深部剪切破裂构造的地震学证据[J]. 地球物理学报,63(2):492–504. doi: 10.6038/cjg2020N0192 Li H,Dong Y B,Wang Y X,Peng Y F,Liu S Q,Wu B Y. 2020. Seismological evidence for a deep-seated shear zone in the Langgu depression[J]. Chinese Journal of Geophysics,63(2):492–504 (in Chinese).
刘保金,曲国胜,孙铭心,刘亢,赵成彬,徐锡伟,酆少英,寇昆朋. 2011. 唐山地震区地壳结构和构造:深地震反射剖面结果[J]. 地震地质,33(4):901–912. doi: 10.3969/j.issn.0253-4967.2011.04.014 Liu B J,Qu G S,Sun M X,Liu K,Zhao C B,Xu X W,Feng S Y ,Kou K P. 2011. Crustal structures and tectonics of Tangshan earthquake area:Results from deep seismic reflection profiling[J]. Seismology and Geology,33(4):901–912 (in Chinese).
刘国栋,顾群,史书林,孙洁,石障松,刘金汉. 1983. 京津唐渤和周围地区地壳上地幔电性结构及其与地震活动性的关系[J]. 地球物理学报,26(2):149–157. doi: 10.3321/j.issn:0001-5733.1983.02.006 Liu G D,Gu Q,Shu S L,Sun J,Shi Z S,Liu J H. 1983. The electrical structure of the crust and upper mantle and its relationship with seismicity in the Beijing-Tianjin-Tangshan region and adjacent area[J]. Acta Geophysica Sinica,26(2):149–157 (in Chinese).
刘国栋,史书林,王宝钧. 1984. 华北地区壳内高导层及其与地壳构造活动性的关系[J]. 中国科学:B辑,14(9):839–848. Liu G D,Shi S L,Wang B J. 1984. The relationship between the high conductivity layer in the crust and its tectonic activity in North China[J]. Science in China :Series B,14(9):839–848 (in Chinese).
罗艳,崇加军,倪四道,陈棋福,陈颙. 2008. 首都圈地区莫霍面起伏及沉积层厚度[J]. 地球物理学报,51(4):1135–1145. doi: 10.3321/j.issn:0001-5733.2008.04.022 Luo Y,Chong J J,Ni S D,Chen Q F,Chen Y. 2008. Moho depth and sedimentary thickness in Capital region[J]. Chinese Journal of Geophysics,51(4):1135–1145 (in Chinese).
罗艳,曾祥方,倪四道. 2013. 震源深度测定方法研究进展[J]. 地球物理学进展,28(5):2309–2321. doi: 10.6038/pg20130513 Luo Y,Zeng X F,Ni S D. 2013. Progress on the determination of focal depth[J]. Progress in Geophysics,28(5):2309–2321 (in Chinese).
马宗晋,薛峰. 1983. 中国大陆地震深度分布与“易震层”初探[J]. 地震科学研究,3(3):43–46. Ma Z J,Xue F. 1983. Preliminary study on the depth distribution of earthquakes in China and the “Easy Layer”[J]. Earthquake Science Research,3(3):43–46 (in Chinese).
马宗晋,张家声,刘国栋,刘若新. 1990. 大陆多震层研究现状和讨论[J]. 地震地质,12(3):262–264. Ma Z J,Zhang J S,Liu G D,Liu R X. 1990. Current status and discussion of multi-seismic strata in the mainland[J]. Seismology and Geology,12(3):262–264 (in Chinese).
孙若昧,刘福田. 1995. 京津唐地区地壳结构与强震的发生:Ⅰ. P波速度结构[J]. 地球物理学报,38(5):599–607. doi: 10.3321/j.issn:0001-5733.1995.05.006 Sun R M,Liu F T. 1995. Crust structure and strong earthquake in Beijing,Tianjin,Tangshan area:Ⅰ. P wave velocity structure[J]. Acta Geophysica Sinica,38(5):599–607 (in Chinese).
孙若昧,赵燕来,吴丹. 1996. 京津唐地区地壳结构与强震的发生:Ⅱ. S波速度结构[J]. 地球物理学报,39(3):347–355. doi: 10.3321/j.issn:0001-5733.1996.03.008 Sun R M,Zhao Y L,Wu D. 1996. Crust structures and strong earthquake in Beijing,Tianjin,Tangshan area:Ⅱ. S wave velocity structure[J]. Acta Geophysica Sinica,39(3):347–355 (in Chinese).
孙玉军,董树文,范桃园,张怀,石耀霖. 2013. 中国大陆及邻区岩石圈三维流变结构[J]. 地球物理学报,56(9):2936–2946. doi: 10.6038/cjg20130908 Sun Y J,Dong S W,Fan T Y,Zhang H,Shi Y L. 2013. 3D rheological structure of the continental lithosphere beneath China and adjacent regions[J]. Chinese Journal of Geophysics,56(9):2936–2946 (in Chinese).
王椿镛,吴庆举,段永红,王志铄,楼海. 2017. 华北地壳上地幔结构及其大地震深部构造成因[J]. 中国科学:地球科学,47(6):684–719. Wang C Y,Wu Q J,Duan Y H,Wang Z S,Lou H. 2017. Crustal and upper mantle structure and deep tectonic genesis of large earthquakes in North China[J]. Science China Earth Sciences,60(5):821–857. doi: 10.1007/s11430-016-9009-1
谢祖军. 2013. 中国地区基于背景噪声的瑞利面波层析成像及震源参数研究[D]. 北京: 中国科学院大学: 55–56. Xie Z J. 2013. Rayleighian Surface Tomography and Source Parameters Research Based on Background Noise in China[D]. Beijing: University of Chinese Academy of Sciences: 55–56 (in Chinese).
王帅军,张先康,张成科,王夫运,赵金仁,张建狮,刘宝峰,潘素珍,盖玉杰. 2007. 武清—北京—赤城二维地壳结构和构造[J]. 地球物理学报,50(6):1769–1777. doi: 10.3321/j.issn:0001-5733.2007.06.017 Wang S J,Zhang X K,Zhang C K,Wang F Y,Zhao J R,Zhang J S,Liu B F,Pan S Z,Gai Y J. 2007. 2-D crustal structures along Wuqing-Beijing-Chicheng deep seismic sounding profile[J]. Chinese Journal of Geophysics,50(6):1769–1777 (in Chinese).
徐杰, 计凤桔. 2015. 渤海湾盆地构造及其演化[M]. 北京: 地震出版社: 234–256. Xu J, Ji F J. 2015. Tectonics and Evolution of Bohai Bay Basin[M]. Beijing: Seismological Press: 234–256.
徐锡伟, 吴卫民, 张先康. 2002. 首都圈地区地壳最新构造变动与地震[M]. 北京: 科学出版社: 134–154. Xu X W, Wu W M, Zhang X K. 2002. The Latest Tectonic Changes and Earthquakes in the Crust of the Capital Zone[M]. Beijing: Science Press: 134–154 (in Chinese).
徐亚,郝天珧,黄松,李志伟,吕川川,赵百民,胡卫剑. 2011. 渤海湾地区壳幔结构重磁综合研究[J]. 地球物理学报,54(12):3344–3351. doi: 10.3969/j.issn.0001-5733.2011.12.032 Xu Y,Hao T Y,Huang S,Li Z W,Lü C C,Zhao B M,Hu W J. 2011. Crustal and mantle structure of the Bohai Bay area based on the gravity and magnetic data[J]. Chinese Journal of Geophysics,54(12):3344–3351 (in Chinese).
杨歧焱,吴庆举,盛艳蕊,高家乙,宋键,邸龙. 2018. 张渤地震带及邻区近震体波成像及孕震环境分析[J]. 地球物理学报,61(8):3251–3262. doi: 10.6038/cjg2018L0628 Yang Q Y,Wu Q J,Sheng Y R,Gao J Y,Song J,Di L. 2018. Regional seismic body wave tomography and deep seismogenic environment beneath Zhangbo seismic belt and its adjacent area[J]. Chinese Journal of Geophysics,61(8):3251–3262 (in Chinese).
曾融生,朱露培,何正勤,丁志峰,孙为国. 1991. 华北盆地强震的震源模型兼论强震和盆地的成因[J]. 地球物理学报,34(3):288–301. doi: 10.3321/j.issn:0001-5733.1991.03.004 Zeng R S,Zhu L P,He Z Q,Ding Z F,Sun W G. 1991. A seismic source model of the large earthquakes in North China extensional basin and discussions on the genetic processes of the extensional basin and earthquakes[J]. Acta Geophysica Sinica,34(3):288–301 (in Chinese).
张国民,汪素云,李丽,张晓东,马宏生. 2002. 中国大陆地震震源深度及其构造含义[J]. 科学通报,47(9):663–668. doi: 10.3321/j.issn:0023-074X.2002.09.004 Zhang G M,Wang S Y,Li L,Zhang X D,Ma H S. 2002. Focal depth research of earthquakes in mainland China:Implication for tectonics[J]. Chinese Science Bulletin,47(12):969–974.
赵博,高原,石玉涛. 2013. 用双差定位结果分析华北地区的地震活动[J]. 地震,33(1):12–21. doi: 10.3969/j.issn.1000-3274.2013.01.002 Zhao B,Gao Y,Shi Y T. 2013. Relocation of small earthquakes in North China using double difference algorithm[J]. Earthquake,33(1):12–21 (in Chinese).
赵成彬,刘保金,姬计法,酆少英,石金虎. 2013. 北京南部地壳精细结构深地震反射探测研究[J]. 地球物理学报,56(4):1168–1176. doi: 10.6038/cjg20130412 Zhao C B,Liu B J,Ji J F,Feng S Y,Shi J H. 2013. Fine crustal structure in the south of Beijing revealed by deep seismic reflection profiling[J]. Chinese Journal of Geophysics,56(4):1168–1176 (in Chinese).
赵金仁,张先康,张成科,张建狮,杨卓欣,刘宝峰,刘保金,赵成斌. 2004. 利用宽角反射/折射和深反射探测剖面揭示三河—平谷大震区深部结构特征[J]. 地球物理学报,47(4):646–653. doi: 10.3321/j.issn:0001-5733.2004.04.015 Zhao J R,Zhang X K,Zhang C K,Zhang J S,Yang Z X,Liu B F,Liu B J,Zhao C B. 2004. Deep structural features of the Sanhe-Pinggu great earthquake area imaged by wide-angle and deep seismic reflection profiling[J]. Chinese Journal of Geophysics,47(4):646–653 (in Chinese).
Scholz C H. 2002. The Mechanics of Earthquakes and Faulting[M]. 2nd ed. Cambridge: Cambridge University Press: 167–174.
Stein S,Wiens D A. 1986. Depth determination for shallow teleseismic earthquakes:Methods and results[J]. Rev Geophys,24(4):806–832. doi: 10.1029/RG024i004p00806
Waldhauser F,Ellsworth W L. 2000. A double-difference earthquake location algorithm:Method and application to the Northern Hayward Fault,California[J]. Bull Seismol Soc Am,90(6):1353–1368. doi: 10.1785/0120000006
Zhao L S,Helmberger D V. 1994. Source estimation from broadband regional seismograms[J]. Bull Seismol Soc Am,84(1):91–104.
Zhu L P,Helmberger D V. 1996. Advancement in source estimation techniques using broadband regional seismograms[J]. Bull Seismol Soc Am,86(5):1634–1641.
Zhu L P,Rivera L A. 2002. A note on the dynamic and static displacements from a point source in multilayered media[J]. Geophys J Int,148(3):619–627. doi: 10.1046/j.1365-246X.2002.01610.x
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