Analysis of dynamic characteristics of gravity field before and after the 2021 Yangbi MS6.4 earthquake
-
摘要:
基于2015年以来南北地震带南段相对重力和绝对重力观测资料，系统分析了区域重力场动态变化及其与2021年5月21日漾濞MS6.4地震的关系。结果表明：① 区域重力场变化与维西—乔后断裂关系密切，反映了2015—2021年期间该断裂活动引起了地表重力场变化；② 与漾濞地震孕育有关的重力场经历了“弱变化—区域性异常—局部异常—四象限分布异常—大范围的正异常—反向变化发震”的演化过程；③ 重力场累积变化和差分变化图像均反映出漾濞震前两年出现显著的重力异常变化，地震发生在重力变化梯度带、四象限中心和零等值线拐弯附近；④ 重力场动态演化图像较好地反映了漾濞MS6.4地震孕育发生过程中出现的中期前兆现象，并基于该现象在漾濞MS6.4地震前作过一定程度的中期预测，尤其是强震地点判定。
Abstract:Based on the observation data of relative gravity and absolute gravity in the southern section of the South-North Seismic Belt since 2015, we have systematically analyzed the dynamic change of regional gravity field and its relationship with the occurrence of Yangbi MS6.4 earthquake on May 21, 2021. The results show that: ① The change of regional gravity field is closely related to the Weixi-Qiaohou fault, which reflects that the fault activity caused the change of surface gravity field from 2015 to 2021; ② The gravity field change related to the preparation of Yangbi earthquake has experienced the evolution process of “steady state-regional gravity anomaly-local gravity anomaly-four-quadrant distribution-large area positive anomaly-earthquake occurring in the reverse change process”; ③ The images of cumulative change and differential change of gravity field show that there were significant gravity anomalies in the two years before Yangbi earthquake, and the earthquake occurred in the gradient zone of gravity change, the center of the four-quadrants and near the zero contour curve; ④ The dynamic evolution image of gravity field can well reflect the medium-term precursory phenomena during the preparation of Yangbi MS6.4 earthquake, and based on this phenomenon, a certain degree of medium-term prediction was made before Yangbi MS6.4 earthquake, especially the determination of strong earthquake location.
-
Keywords:
- South-North Seismic Belt /
- Yangbi earthquake /
- gravity observation /
- gravity change
-
-
![]()
图 1 南北地震带南段重力测点、联测路线及活动断裂分布图
Figure 1. Distribution of gravity measurement points，measurement routes and active faults in the southern section of the South-North Seismic Belt
![]()
图 2 漾濞地震前后重力场差分动态变化图像
（a） 2015年9月—2016年9月；（b） 2016年9月—2017年9月；（c） 2017年9月—2018年9月；（d） 2018年9月—2019年9月；（e） 2019年9月—2020年9月；（f） 2020年9月—2021年9月
Figure 2. Differential dynamic change images of gravity field before and after Yangbi earthquake
（a） September 2015−September 2016；（b） September 2016−September 2017；（c） September 2017−September 2018；（d） September 2018−September 2019；（e） September 2019−September 2020；（f） September 2020−September 2021
![]()
图 3 漾濞地震前2年尺度重力场累积变化图像
（a） 2016年9月—2018年9月；（b） 2018年9月—2020年9月
Figure 3. Cumulative change images of the gravity field during a two-years period before the Yangbi earthquake
（a） September 2016−September 2018；（b） September 2018−September 2020
![]()
图 4 漾濞震中附近测点重力时序变化图
（a） 维西—乔后断裂西侧；（b） 维西—乔后断裂东侧
Figure 4. Time series change of gravity at survey points near the epicenter of Yangbi earthquake
（a） West side of the Weixi−Qiaohou fault；（b） East side of the Weixi−Qiaohou fault
表 1 南北地震带南段测网资料
Table 1 Information of gravity survey network in the southern section of the South-North Seismic Belt
观测时间段 观测仪器 点值平均精度/（10−8 m·s−2） 观测时间段 观测仪器 点值平均精度/（10−8 m·s−2） 2015年7—9月 C169，C170 11.2 2019年7—9月 C169，C170 9.2 2016年7—9月 C169，C170 10.3 2020年7—9月 C169，C170 7.4 2017年7—9月 C169，C170 11.0 2021年7—9月 C169，C170 9.0 2018年7—9月 C834，C845 9.1 
下载: 导出CSV
-
常祖峰,常昊,臧阳,代博洋. 2016. 维西—乔后断裂新活动特征及其与红河断裂的关系[J]. 地质力学学报,22(3):517–530. doi: 10.3969/j.issn.1006-6616.2016.03.009 Chang Z F,Chang H,Zang Y,Dai B Y. 2016. Recent active features of Weixi-Qiaohou fault and its relationship with the Honghe fault[J]. Journal of Geomechanics,22(3):517–530 (in Chinese).
陈运泰,顾浩鼎,卢造勋. 1980. 1975年海城地震与1976年唐山地震前后的重力变化[J]. 地震学报,2(1):21–31. Chen Y T,Gu H D,Lu Z X. 1980. Variations of gravity before and after the Haicheng earthquake,1975 and the Tangshan earthquake,1976[J]. Acta Seismologica Sinica,2(1):21–31 (in Chinese).
邓起东,张培震,冉勇康,杨晓平,闵伟,楚全芝. 2002. 中国活动构造基本特征[J]. 中国科学:D辑,32(12):1020–1030. Deng Q D,Zhang P Z,Ran Y K,Yang X P,Min W,Chu Q Z. 2003. Basic characteristics of active tectonics of China[J]. Science in China:Series D,46(4):356–372.
段梦乔,赵翠萍,周连庆,赵策,左可桢. 2021. 2021年5月21日云南漾濞MS6.4地震序列发震构造[J]. 地球物理学报,64(9):3111–3125. doi: 10.6038/cjg2021P0423 Duan M Q,Zhao C P,Zhou L Q,Zhao C,Zuo K Z. 2021. Seismogenic structure of the 21 May 2021 MS6.4 Yunnan Yangbi earthquake sequence[J]. Chinese Journal of Geophysics,64(9):3111–3125 (in Chinese).
顾功叙,郭宗汾,刘克人,郑金涵,卢红艳,刘端法. 1997. 中国京津唐张地区时间上连续的重力变化与地震的孕育和发生[J]. 科学通报,42(18):1919–1930. doi: 10.3321/j.issn:0023-074X.1997.18.003 Gu G X,Kuo J T,Liu K R,Zheng J H,Lu H Y,Liu D F. 1997. Time-continuous gravity changes and the pregnancy and occurrence of earthquakes in Beijing-Tianjin-Tangshan-Zhangjiakou regions[J]. Chinese Science Bulletin,42(18):1919–1930 (in Chinese). doi: 10.1360/csb1997-42-18-1919
李大虎,丁志峰,吴萍萍,刘韶,邓菲,张旭,赵航. 2021. 2021年5月21日云南漾濞MS6.4地震震区地壳结构特征与孕震背景[J]. 地球物理学报,64(9):3083–3100. doi: 10.6038/cjg2021P0405 Li D H,Ding Z F,Wu P P,Liu S,Deng F,Zhang X,Zhao H. 2021. The characteristics of crustal structure and seismogenic background of Yangbi MS6.4 earthquake on May 21,2021 in Yunnan Province,China[J]. Chinese Journal of Geophysics,64(9):3083–3100 (in Chinese).
龙锋,祁玉萍,易桂喜,吴微微,王光明,赵小艳,彭关灵. 2021. 2021年5月21日云南漾濞MS6.4地震序列重新定位与发震构造分析[J]. 地球物理学报,64(8):2631–2646. doi: 10.6038/cjg2021O0526 Long F,Qi Y P,Yi G X,Wu W W,Wang G M,Zhao X Y,Peng G L. 2021. Relocation of the MS6.4 Yangbi earthquake sequence on May 21,2021 in Yunnan Province and its seismogenic structure analysis[J]. Chinese Journal of Geophysics,64(8):2631–2646 (in Chinese).
马瑾,Sherman S I,郭彦双. 2012. 地震前亚失稳应力状态的识别:以5°拐折断层变形温度场演化的实验为例[J]. 中国科学:地球科学,42(5):633–645. Ma J,Sherman S I,Guo Y S. 2012. Identification of meta-instable stress state based on experimental study of evolution of the temperature field during stick-slip instability on a 5° bending fault[J]. Science China Earth Sciences,55(6):869–881. doi: 10.1007/s11430-012-4423-2
马瑾,郭彦双. 2014. 失稳前断层加速协同化的实验室证据和地震实例[J]. 地震地质,36(3):547–561. doi: 10.3969/j.issn.0253-4967.2014.03.001 Ma J,Guo Y S. 2014. Accelerated synergism prior to fault instability:Evidence from laboratory experiments and an earthquake case[J]. Seismology and Geology,36(3):547–561 (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).
申重阳,李辉,孙少安,杨光亮,玄松柏,谈洪波,刘少明. 2010. 2008年于田MS7.3地震前重力场动态变化特征分析[J]. 大地测量与地球动力学,30(4):1–7. doi: 10.3969/j.issn.1671-5942.2010.04.001 Shen C Y,Li H,Sun S A,Yang G L,Xuan S B,Tan H B,Liu S M. 2010. Characteristic analysis of dynamic gravity change before Yutian MS7.3 earthquake,2008[J]. Journal of Geodesy and Geodynamics,30(4):1–7 (in Chinese).
孙和平. 2004. 重力场的时间变化与地球动力学[J]. 中国科学院院刊,19(3):189–193. doi: 10.3969/j.issn.1000-3045.2004.03.008 Sun H P. 2004. Temporal variation of gravity field and geodynamics[J]. Bulletin of the Chinese Academy of Sciences,19(3):189–193 (in Chinese).
王光明,吴中海,彭关灵,刘自凤,罗睿洁,黄小龙,陈浩朋. 2021. 2021年5月21日漾濞MS6.4地震的发震断层及其破裂特征:地震序列的重定位分析结果[J]. 地质力学学报,27(4):662–678. doi: 10.12090/j.issn.1006-6616.2021.27.04.055 Wang G M,Wu Z H,Peng G L,Liu Z F,Luo R J,Huang X L,Chen H P. 2021. Seismogenic fault and it’s rupture characteristics of the 21 May,2021 Yangbi MS6.4 earthquake:Analysis results from the relocation of the earthquake sequence[J]. Journal of Geomechanics,27(4):662–678 (in Chinese).
隗寿春,祝意青,赵云峰,张松,刘芳,李瑞,高铎文. 2020. 呼图壁MS6.2地震前后重力变化特征分析[J]. 地震地质,42(4):923–935. doi: 10.3969/j.issn.0253-4967.2020.04.010 Wei S C,Zhu Y Q,Zhao Y F,Zhang S,Liu F,Li R,Gao D W. 2020. Study on characteristics of gravity variation before and after Hutubi MS6.2 earthquake[J]. Seismology and Geology,42(4):923–935 (in Chinese).
吴中海,龙长兴,范桃园,周春景,冯卉,杨振宇,仝亚博. 2015. 青藏高原东南缘弧形旋扭活动构造体系及其动力学特征与机制[J]. 地质通报,34(1):1–31. doi: 10.3969/j.issn.1671-2552.2015.01.002 Wu Z H,Long C X,Fan T Y,Zhou C J,Feng H,Yang Z Y,Tong Y B. 2015. The arc rotational-shear active tectonic system on the southeastern margin of Tibetan Plateau and its dynamic characteristics and mechanism[J]. Geological Bulletin of China,34(1):1–31 (in Chinese).
徐锡伟,闻学泽,郑荣章,马文涛,宋方敏,于贵华. 2003. 川滇地区活动块体最新构造变动样式及其动力来源[J]. 中国科学:D辑,33(增刊1):151–162. Xu X W,Wen X Z,Zheng R Z,Ma W T,Song F M,Yu G H. 2003. Pattern of latest tectonic motion and its dynamics for active blocks in Sichuan-Yunnan region,China[J]. Science in China:Series D,46(S2):210–226.
杨雄,祝意青,申重阳,赵云峰. 2021. 2019年甘肃夏河MS5.7地震前后重力场异常特征分析[J]. 地球科学进展,36(5):510–519. Yang X,Zhu Y Q,Shen C Y,Zhao Y F. 2021. Analysis on the characteristics of gravity field anomalies before and after the Xiahe MS5.7 earthquake in Gansu in 2019[J]. Advances in Earth Science,36(5):510–519 (in Chinese).
祝意青,梁伟锋,徐云马. 2008. 重力资料对2008年汶川MS8.0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).
祝意青,梁伟锋,湛飞并,刘芳,徐云马,郭树松,刘练. 2012. 中国大陆重力场动态变化研究[J]. 地球物理学报,55(3):804–813. doi: 10.6038/j.issn.0001-5733.2012.03.010 Zhu Y Q,Liang W F,Zhan F B,Liu F,Xu Y M,Guo S S,Liu L. 2012. Study on dynamic change of gravity field in China continent[J]. Chinese Journal of Geophysics,55(3):804–813 (in Chinese).
祝意青,闻学泽,孙和平,郭树松,赵云峰. 2013. 2013年四川芦山MS7.0地震前的重力变化[J]. 地球物理学报,56(6):1887–1894. doi: 10.6038/cjg20130611 Zhu Y Q,Wen X Z,Sun H P,Guo S S,Zhao Y F. 2013. Gravity changes before the Lushan,Sichuan,MS=7.0 earthquake of 2013[J]. Chinese Journal of Geophysics,56(6):1887–1894 (in Chinese).
祝意青,赵云峰,李铁明,梁伟锋,徐云马,郭树松. 2014. 2013年甘肃岷县漳县6.6级地震前后重力场动态变化[J]. 地震地质,36(3):667–676. doi: 10.3969/j.issn.0253-4967.2014.03.010 Zhu Y Q,Zhao Y F,Li T M,Liang W F,Xu Y M,Guo S S. 2014. Dynamic variation of gravity field before and after the Minxian-Zhangxian MS6.6 earthquake on July 22,2013,Gansu,China[J]. Seismology and Geology,36(3):667–676 (in Chinese).
祝意青,刘芳,李铁明,郑兵,王青华. 2015. 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. 2015. 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).
祝意青,李铁明,郝明,梁伟锋,赵云峰,徐云马,郝庆花. 2016. 2016年青海门源MS6.4地震前重力变化[J]. 地球物理学报,59(10):3744–3752. doi: 10.6038/cjg20161019 Zhu Y Q,Li T M,Hao M,Liang W F,Zhao Y F,Xu Y M,Hao Q H. 2016. Gravity changes before the Menyuan,Qinghai MS6.4 earthquake of 2016[J]. Chinese Journal of Geophysics,59(10):3744–3752 (in Chinese).
祝意青,梁伟锋,赵云峰,刘芳,隗寿春,徐云马. 2017. 2017年四川九寨沟MS7.0地震前区域重力场变化[J]. 地球物理学报,60(10):4124–4131. doi: 10.6038/cjg20171037 Zhu Y Q,Liang W F,Zhao Y F,Liu F,Wei S C,Xu Y M. 2017. Gravity changes before the Jiuzhaigou,Sichuan,MS7.0 earthquake of 2017[J]. Chinese Journal of Geophysics,60(10):4124–4131 (in Chinese).
祝意青,刘芳,张国庆,赵云峰,隗寿春. 2022. 中国流动重力监测与地震预测[J]. 武汉大学学报(信息科学版),47(6):820–829. Zhu Y Q,Liu F,Zhang G Q,Zhao Y F,Wei S C. 2022. Mobile gravity monitoring and earthquake prediction in China[J]. Geomatics and Information Science of Wuhan University,47(6):820–829 (in Chinese).
Chen S,Liu M,Xing L L,Xu W M,Wang W X,Zhu Y Q,Li H. 2016. Gravity increase before the 2015 MW7.8 Nepal earthquake[J]. Geophys Res Lett,43(1):111–117. doi: 10.1002/2015GL066595
Li H,Shen C Y,Sun S A,Wang X Q,Xiang A M,Liu S M. 2011. Recent gravity changes in China Mainland[J]. Geodesy and Geodynamics,2(1):1–12. doi: 10.3724/SP.J.1246.2011.00001
Zhu Y Q,Zhan F B,Zhou J C,Liang W F,Xu Y M. 2010. Gravity measurements and their variations before the 2008 Wenchuan earthquake[J]. Bull Seismol Soc Am,100(5B):2815–2824. doi: 10.1785/0120100081
计量
- 文章访问数: 131
- HTML全文浏览量: 49
- PDF下载量: 39
