Li Honglei, Chen Shi. 2019: Crustal density variation and its relationship with the seismogenic structure of strong earthquakes in Sichuan-Yunnan region. Acta Seismologica Sinica, 41(5): 600-612. DOI: 10.11939/jass.20190029
Citation: Li Honglei, Chen Shi. 2019: Crustal density variation and its relationship with the seismogenic structure of strong earthquakes in Sichuan-Yunnan region. Acta Seismologica Sinica, 41(5): 600-612. DOI: 10.11939/jass.20190029

Crustal density variation and its relationship with the seismogenic structure of strong earthquakes in Sichuan-Yunnan region

More Information
  • Received Date: February 14, 2019
  • Revised Date: May 13, 2019
  • Available Online: October 14, 2019
  • Published Date: August 31, 2019
  • In order to study the relationship between the spatio-temporal evolution characteris-tics of crustal density and the seismogenic process of strong earthquakes in Sichuan-Yunnan region, this paper obtained the three-dimensional dynamic density variation model of 0−60 km depth with the resolution of 55 km×55 km×10 km (length, width and height) based on the re-measurement gravity data in the Sichuan-Yunnan region during the period 2011−2014 by the damped least squares inversion algorithm. Then we analyzed the relationship between the three-dimensional dynamic density structure characteristics and the seismogenic characteristics of the LushanMS7.0 in 2013, the Ludian MS6.5 in 2014 and the Kangding MS6.3 in 2014. Furthermore we studied the deep crustal structure, seismogenic background, and regional dynamics of the strong earthquakes. The results show that density variation model exhibited multiple density-change high-gradient zones, which is consistent with the extending direction of the main active fault zones in the Sichuan-Yunnan region. There were obvious regional density variation anomalies in the epicentral area of the three earthquakes mentioned above. The density change horizontal profiles in the depth of 15−35 km showed that strong earthquakes were likely to occur in the center of the high-gradient transition of the positive and negative density variation as well as the center of the four-quadrant distribution of the density variation in the upper-crust, and low density-change anomalies in the mid-crust is required for strong earthquakes. In the lower-crust low anomalies and the high gradient zone of the density change may be the main medium structure for the strong earthquakes. The density variation along the vertical section in the depth of 0−50 km shows that decoupling changes appeared in the shallow crust and deep crust of the epicenters and their adjacent areas. The transitional zone between positive and negative density variation in vertical direction in the crust maybe the main structure for occurrence of strong earthquakes.
  • 陈石,王青华,王谦身,王岩,卢红艳,徐伟民,石磊,郭凤义. 2014. 云南鲁甸MS6.5地震震源区和周边三维密度结构及重力场变化[J]. 地球物理学报,57(9):3080–3090. doi: 10.6038/cjg20140933
    Chen S,Wang Q H,Wang Q S,Wang Y,Lu H Y,Xu W M,Shi L,Guo F Y. 2014. The 3D density structure and gravity change of Ludian MS6.5 Yunnan epicenter and surrounding region[J]. Chinese Journal of Geophysics,57(9):3080–3090 (in Chinese). doi: 10.6038/cjg20140933(inChinese)
    郝明. 2012. 基于精密水准数据的青藏高原东缘现今地壳垂直运动与典型地震同震及震后垂直形变研究[D]. 北京: 中国地震局地质研究所: 56−57.
    Hao M. 2012. Present Crustal Vertical Movement of Eastern Tibetan Plateau and Coseismic and Postseismic Vertical Deformation of Two Typical Earthquakes[D]. Beijing: Institute of Geology, China Earthquake Administration: 56−57 (in Chinese).
    侯强,邹文远,欧明霖,丁小军. 2018. 青藏高原东南缘壳幔力学耦合及其动力学意义[J]. 大地测量与地球动力学,38(10):991–1000.
    Hou Q,Zou W Y,Ou M L,Ding X J. 2018. Mechanical coupling in southeastern Qinghai-Tibetan Plateau and its geodynamic implications[J]. Journal of Geodesy and Geodynamics,38(10):991–1000 (in Chinese).
    李红蕾,方剑,王新胜,刘杰,崔荣花,陈铭. 2017. 重力及重力梯度联合反演青藏高原及邻区岩石圈三维密度结构[J]. 地球物理学报,60(6):2469–2479. doi: 10.6038/cjg20170634
    Li H L,Fang J,Wang X S,Liu J,Cui R H,Chen M. 2017. Lithospheric 3-D density structure beneath the Tibetan Plateau and adjacent areas derived from joint inversion of satellite gravity and gravity-gradient data[J]. Chinese Journal of Geophysics,60(6):2469–2479 (in Chinese). doi: 10.6038/cjg20170634(inChinese)
    梁伟锋,刘芳,徐云马,祝意青,郭树松,赵云峰,刘练. 2013. 青藏高原东缘重力观测及对芦山M7.0地震的反映[J]. 地震工程学报,35(2):266–271. doi: 10.3969/j.issn.1000-0844.2013.02.0266
    Liang W F,Liu F,Xu Y M,Zhu Y Q,Guo S S,Zhao Y F,Liu L. 2013. Gravity observation in the eastern margin of Qinghai-Tibetan Plateau and reflect to the Lushan M7.0 earthquake[J]. China Earthquake Engineering Journal,35(2):266–271 (in Chinese).
    楼海,王椿镛. 2005. 川滇地区重力异常的小波分解与解释[J]. 地震学报,27(5):515–523. doi: 10.3321/j.issn:0253-3782.2005.05.006
    Lou H,Wang C Y. 2005. Wavelet analysis and interpretation of gravity data in Sichuan-Yunnan region,China[J]. Acta Seismologica Sinica,27(5):515–523 (in Chinese).
    孟小红,石磊,郭良辉,佟拓,张盛. 2012. 青藏高原东北缘重力异常多尺度横向构造分析[J]. 地球物理学报,55(12):3933–3941. doi: 10.6038/j.issn.0001-5733.2012.12.006
    Meng X H,Shi L,Guo L H,Tong T,Zhang S. 2012. Multi-scale analyses of transverse structures based on gravity anomalies in the northeastern margin of the Tibetan Plateau[J]. Chinese Journal of Geophysics,55(12):3933–3941 (in Chinese). doi: 10.6038/j.issn.0001-5733.2012.12.006(inChinese)
    申重阳. 2005. 地壳形变与密度变化耦合运动探析[J]. 大地测量与地球动力学,25(3):7–12.
    Shen C Y. 2005. Preliminary analysis of coupling movement between crustal deformation and density change[J]. Journal of Geodesy and Geodynamics,25(3):7–12 (in Chinese).
    申重阳,李辉,孙少安,刘少明,玄松柏,谈洪波. 2009. 重力场动态变化与汶川MS8.0地震孕育过程[J]. 地球物理学报,52(10):2547–2557. doi: 10.3969/j.issn.0001-5733.2009.10.013
    Shen C Y,Li H,Sun S A,Liu S M,Xuan S B,Tan H B. 2009. Dynamic variations of gravity and the preparation process of the Wenchuan MS8.0 earthquake[J]. Chinese Journal of Geophysics,52(10):2547–2557 (in Chinese).
    王椿镛,李永华,楼海. 2016. 与青藏高原东北部地球动力学相关的深部构造问题[J]. 科学通报,61(20):2239–2263.
    Wang C Y,Li Y H,Lou H. 2016. Issues on crustal and upper-mantle structures associated with geodynamics in the northeastern Tibetan Plateau[J]. Chinese Science Bulletin,61(20):2239–2263 (in Chinese). doi: 10.1360/N972016-00160
    王嘉沛,申重阳,玄松柏,杨光亮,郝洪涛. 2018. 2017年四川九寨沟MS7.0地震震前地壳密度变化特征[J]. 大地测量与地球动力学,38(8):771–776.
    Wang J P,Shen C Y,Xuan S B,Yang G L,Hao H T. 2018. Density variation in the crust before the Jiuzhaigou,Sichuan,MS7.0 earthquake of 2017[J]. Journal of Geodesy and Geodynamics,38(8):771–776 (in Chinese).
    王绪本,高原,王志,余嘉顺. 2017. 青藏高原东缘深部地球物理与大陆动力学研究进展[J]. 地球物理学报,60(6):2030–2037. doi: 10.6038/cjg20170601
    Wang X B,Gao Y,Wang Z,Yu J S. 2017. Research progress on deep geophysics and continental dynamics in eastern Tibetan Plateau[J]. Chinese Journal of Geophysics,60(6):2030–2037 (in Chinese). doi: 10.6038/cjg20170601(inChinese)
    闻学泽,杜方,易桂喜,龙锋,范军,杨攀新,熊仁伟,刘晓霞,刘琦. 2013. 川滇交界东段昭通、莲峰断裂带的地震危险背景[J]. 地球物理学报,56(10):3361–3372. doi: 10.6083/cjg20131012
    Wen X Z,Du F,Yi G X,Long F,Fan J,Yang P X,Xiong R W,Liu X X,Liu Q. 2013. Earthquake potential of the Zhaotong and Lianfeng fault zones of the eastern Sichuan-Yunnan border region[J]. Chinese Journal of Geophysics,56(10):3361–3372 (in Chinese). doi: 10.6083/cjg20131012(inChinese)
    吴微微,吴朋,魏娅玲,孙玮. 2017. 川滇活动块体中—北部主要活动断裂带现今应力状态的分区特征[J]. 地球物理学报,60(5):1735–1745. doi: 10.6038/cjg20170511
    Wu W W,Wu P,Wei Y L,Sun W. 2017. Regional characteristics of stress state of main seismic active faults in mid-northern part of Sichuan-Yunnan block[J]. Chinese Journal of Geophysics,60(5):1735–1745 (in Chinese). doi: 10.6038/cjg20170511(inChinese)
    许昭永,文丽敏,石宝文,许峻,樊俊屹,李正媛,苏有锦. 2015. 川滇菱形地块的应变能积累释放周期和强震预测[J]. 地震学报,37(5):774–786. doi: 10.11939/jass.2015.05.006
    Xu Z Y,Wen L M,Shi B W,Xu J,Fan J Y,Li Z Y,Su Y J. 2015. The strain energy accumulating-releasing period and strong earthquake prediction in Sichuan-Yunnan rhombic block[J]. Acta Seismologica Sinica,37(5):774–786 (in Chinese). doi: 10.11939/jass.2015.05.006(inChinese)
    杨海燕,胡家富,赵宏,苏有锦. 2009. 川西地区壳幔结构与汶川MS8.0级地震的孕震背景[J]. 地球物理学报,52(2):356–364.
    Yang H Y,Hu J F,Zhao H,Su Y J. 2009. Crust-mantle structure and seismogenic background of Wenchuan MS8.0 earthquake in western Sichuan area[J]. Chinese Journal of Geophysics,52(2):356–364 (in Chinese).
    祝意青,梁伟锋,徐云马. 2008. 重力资料对2008年汶川MS 8.0地震的中期预测[J]. 国际地震动态,(7):36–39. doi: 10.3969/j.issn.0253-4975.2008.07.006
    Zhu Y Q,Liang W F,Xu Y M. 2008. Medium-term prediction of MS8.0 earthquake in Wenchuan,Sichuan by mobile gravity[J]. Recent Developments in World Seismology,(7):36–39 (in Chinese).
    祝意青,徐云马,吕弋培,李铁明. 2009. 龙门山断裂带重力变化与汶川8.0级地震关系研究[J]. 地球物理学报,52(10):2538–2546. doi: 10.3969/j.issn.0001-5733.2009.10.012
    Zhu Y Q,Xu Y M,Lü Y P,Li T M. 2009. Relations between gravity variation of Longmenshan fault zone and Wenchuan MS8.0 earthquake[J]. Chinese Journal of Geophysics,52(10):2538–2546 (in Chinese). doi: 10.3969/j.issn.0001-5733.2009.10.012(inChinese)
    祝意青,刘芳,李铁明,郑兵,王青华. 2015a. 川滇地区重力场动态变化及其强震危险含义[J]. 地球物理学报,58(11):4187–4196. doi: 10.6038/cjg20151125
    Zhu Y Q,Liu F,Li T M,Zheng B,Wang Q H. 2015a. Dynamic variation of the gravity field in the Sichuan-Yunnan region and its implication for seismic risk[J]. Chinese Journal of Geophysics,58(11):4187–4196 (in Chinese). doi: 10.6038/cjg20151125(inChinese)
    祝意青,付广裕,梁伟锋,徐云马. 2015b. 鲁甸 MS6.5、芦山MS7.0、汶川MS8.0地震前区域重力场时变[J]. 地震地质,37(1):319–330. doi: 10.3969/j.issn.0253-4967.2015.01.025
    Zhu Y Q,Fu G Y,Liang W F,Xu Y M. 2015b. Earthquake predictions: Spatial-temporal gravity changes before the Ludian MS6.5,Lushan MS7.0 and Wenchuan MS8.0 earthquakes[J]. Seismology and Geology,37(1):319–330 (in Chinese).
    Backus G E,Gilbert J F. 1967. Numerical applications of a formalism for geophysical inverse problems[J]. Geophys J Int,13(1/2/3):247–276.
    Bai D H,Unsworth M J,Meju M A,Ma X B,Teng J W,Kong X R,Sun Y,Sun J,Wang L F,Liang C S,Zhao C P,Xiao P F,Liu M. 2010. Crustal deformation of the eastern Tibetan Plateau revealed by magnetotelluric imaging[J]. Nat Geosci,3(5):358–362. doi: 10.1038/ngeo830
    Hansen P C. 1992. Analysis of discrete ill-posed problems by means of the L-curve[J]. SIAM Rev,34(4):561–580. doi: 10.1137/1034115
    Jiang W L,Zhang J F,Tian T,Wang T X. 2012. Crustal structure of Chuan-Dian region derived from gravity data and its tectonic implications[J]. Phys Earth Planet Inter,212/213:76–87. doi: 10.1016/j.pepi.2012.07.001
    Lei J S,Zhao D P. 2016. Teleseismic P-wave tomography and mantle dynamics beneath eastern Tibet[J]. Geochem Geophys Geosyst,17(5):1861–1884. doi: 10.1002/2016GC006262
    Li Y G,Oldenburg D W. 1998. 3-D inversion of gravity data[J]. Geophysics,63(1):109–119. doi: 10.1190/1.1444302
    Li Y G. 2001. 3-D inversion of gravity gradiometer data[C]//2001 SEG Annual Meeting. San Antonio, Texas: Society of Exploration Geophysicists: 1470−1473.
    Merriam D F. 2006. The Conrad discontinuity in the Midcontinent (USA)[J]. Trans Kansas Acad Sci,109(3):125–130.
    Zhang G,Wang X B,Fang H,Guo Z M,Zhang Z B,Luo W,Cai X L,Li J,Li Z,Wu X. 2015. Crust and upper mantle electrical resistivity structure in the Panxi region of the eastern Tibetan Plateau and its significance[J]. Acta Geologica Sinica,89(2):531–541. doi: 10.1111/1755-6724.12445
    Zhang J,Li W Y,Tang X C,Tian J,Wang Y C,Guo Q,Pang Z H. 2017. Geothermal data analysis at the high-temperature hydrothermal area in western Sichuan[J]. Science China Earth Science,60(8):1507–1521. doi: 10.1007/s11430-016-9053-2
  • Related Articles

  • Cited by

    Periodical cited type(0)

    Other cited types(1)

Catalog

    Article views (1186) PDF downloads (126) Cited by(1)

    /

    DownLoad:  Full-Size Img  PowerPoint
    Return
    Return