ZHANG Ling,
DU Ai-Min,
LANG Xue et al
.2016.Characteristics of geomagnetic regular diurnal variation before Wenchuan earthquake.Chinese Journal Of Geophysics,59(3): 952-958,doi: 10.6038/cjg20160317
汶川地震前的地磁场日变化特征分析
张凌1, 杜爱民2, 郎雪2,3, 张铁龙4, 杨冬梅5, 赵旭东5
1. 中国地震应急搜救中心, 北京 100049;
2. 中国科学院地质与地球物理研究所, 北京 100029;
3. 中国科学院大学, 北京 100049;
4. Space Research Institute, Austrian Academy of Sciences, Graz, Austria;
5. 中国地震局地球物理研究所, 北京 100081
Characteristics of geomagnetic regular diurnal variation before Wenchuan earthquake
ZHANG Ling1, DU Ai-Min2, LANG Xue2,3, ZHANG Tie-Long4, YANG Dong-Mei5, ZHAO Xu-Dong5
1. National Earthquake Response Support Service, Beijing 100049, China;
2. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China;
3. University of Chinese Academy of Sciences, Beijing 100049, China;
4. Space Research Institute, Austrian Academy of Sciences, Graz, Austria;
5. Institute of Geophysics, China Earthquake Administration, Beijing 100081, China
The characteristics of the geomagnetic daily variation before the Wenchuan earthquake(ML=8) occurring on 2008 May 12 are analyzed by using of the data from ground-based geomagnetic array. The variation of the electromagnetic induced field associated with the geomagnetic daily variation is also discussed. The conclusions are:1) The morphological characteristics of the geomagnetic diurnal variations observed by Chengdu station(CDP)are similar to that observed by other stations; 2) The ratio of Z/H at CDP is greater than that observed by other neighbor stations,with a maximum of Z/H(>2.5)on April 20; 3) The ratio of Z/H at CDP and Z/H at ENS, RCDP/ENS, increases from April 6, reaches a maximum on April 20, then decreases till May 12. The tendency of variations of RCDP/ENS is more apparent for geomagnetic variations with period of 2-4 h. These results indicate that the geomagnetic variation at CDP is partly associated with the conductivity inner the Earth.
Alperovich L S, Zheludev V A. 1999. Long-period geomagnetic precursors of the Loma-Prieta earthquake discovered by wavelet method.//Hayakawa M ed. Atmospheric and Ionospheric Electromagnetic Phenomena Associated with Earthquakes. Tokyo:Terra Scientific Publishing Company, 123-136.
Balasis G, Mandea M. 2007. Can electromagnetic disturbances related to the recent great earthquakes be detected by satellite magnetometers?. Tectonophysics, 431(1-4):173-195.
Campbell W H, Barton C E, Chamalaun F H, et al. 1998. Quiet-day ionospheric currents and their application to upper mantle conductivity in Australia. Earth, Planets Space, 50(4):347-360.
Chen G X, Xu W Y, Du A M, et al. 2007. Statistical characteristics of the day-to-day variability in the geomagnetic Sq field. Journal of Geophysical Research, 112(A6):A06320.
Du A M, Huang Q H, Yang S F. 2002. Epicenter location by abnormal ULF electromagnetic emissions. Geophysical Research Letters, 29(10):94-1-94-3.
Duma G, Ruzhin Y. 2003. Diurnal changes of earthquake activity and geomagnetic Sq-variations. Natural Hazards and Earth System Sciences, 3(3-4):171-177.
Gokhberg M B, Gifeld I L, Rozhnoy A A, et al. 1989. Study of seismic influence on the ionosphere by super long-wave probing of the earth-ionosphere waveguide. Physics of the Earth and Planetary Interiors, 57(1-2):64-67.
Han P, Huang Q H, Xiu J G. 2009. Principal component analysis of geomagnetic diurnal variation associated with earthquakes:case study of the M6.1 Iwate-ken Nairiku Hokubu earthquake. Chinese J. Geophys.(in Chinese), 52(6):1556-1563, doi:10.3969/j.issn.0001-5733.2009.06.017.
Hayakawa M, Kawate R, Molchanov O A, et al. 1996. Results of ultra-low-frequency magnetic field measurements during the Guam earthquake of 8 August 1993. Geophysical Research Letters, 23(3):241-244.
Iyemori T, Nose M, Han D S, et al. 2005. Geomagnetic pulsations caused by the Sumatra earthquake on December 26, 2004. Geophysical Research Letters, 32(20):L20807.
Liu J Y, Chen C H, Chen Y I, et al. 2006a. Seismo-geomagnetic anomalies and M5.0 earthquakes observed in Taiwan during 1988-2001. Physics and Chemistry of the Earth, 31(4-9):215-222.
Liu J Y, Tsai Y B, Chen S W, et al. 2006b. Giant ionospheric disturbances excited by the M9.3 Sumatra earthquake of 26 December 2004. Geophysical Research Letters, 33(2):L02103.
Lockner D A, Byerlee J D. 1985. Complex resistivity of fault gouge and its significance for earthquake lights and induced polarization. Geophysical Research Letters, 12(4):211-214.
Molchanov O A, Hayakawa M. 1995. Generation of ULF electromagnetic emissions by microfracturing. Geophysical Research Letters, 22(22):3091-3094.
Prattes G, Schwingenschuh K, Eichelberger H U, et al. 2011. Ultra Low Frequency(ULF) European multi station magnetic field analysis before and during the 2009 earthquake at L'Aquila regarding regional geotechnical information. Natural Hazards and Earth System Sciences, 11(7):1959-1968.
Rabeh T, Miranda M, Hvozdara M. 2010. Strong earthquakes associated with high amplitude daily geomagnetic variations. Natural Hazards, 53(3):561-574.
Wang Y, Du A M, Chen G X, et al. 2014. Comparing the diurnal variations in the SuperMAG auroral electrojet indices SML and SMU. Chinese Science Bulletin, 59(29-30):3877-3883.
Yang S F, Chen B S, Du A M, et al. 1999. Effect of geomagnetic pulsations during earthquakes. Progress in Geophysics(in Chinese), 14(1):104-114.
Zhao X D, Du A M, Xu W Y, et al. 2008. The origin of the prenoon-postnoon asymmetry for Sq current system. Chinese J. Geophys.(in Chinese), 51(3):643-649, doi:10.3321/j.issn:0001-5733.2008.03.005.
Zhao X D, Du A M, Chen H R, et al. 2010. nversion of the Sq current system and the geomagnetic diurnal variation model. Progress in Geophysics(in Chinese), 25(6):1959-1967, doi:10.3969/j.issn.1004-2903.2010.06.010.
丁鉴海, 车时, 余素荣等. 2009. 地磁日变地震预报方法及其震例研究. 北京:地震出版社.
杜爱民,周志坚,徐文耀,杨少峰. 2004. 新疆和田ML7.1地震前ULF电磁辐射的激发机理. 地球物理学报, 47(5):832-837.
韩鹏, 黄清华, 修济刚. 2009. 地磁日变与地震活动关系的主成分分析——以日本岩手县北部6.1级地震为例. 地球物理学报, 52(6):1556-1563, doi:10.3969/j.issn.0001-5733.2009.06.017.
徐文耀. 2009. 地球电磁现象学. 合肥:中国科学技术大学出版社.
杨少峰, 陈宝生, 杜爱民等. 1999. 地震期间的地磁脉动效应. 地球物理学进展, 14(1):104-114.
赵旭东, 杜爱民, 徐文耀等. 2008. Sq电流系午前午后不对称性现象的来源. 地球物理学报, 51(3):643-649, doi:10.3321/j.issn:0001-5733.2008.03.005.
赵旭东, 杜爱民, 陈化然等. 2010. Sq电流体系的反演与地磁日变模型的建立. 地球物理学进展, 25(6):1959-1967, doi:10.3969/j.issn.1004-2903.2010.06.010.