基于磁通门秒值数据的地震ULF磁场可靠信息提取研究
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摘要
利用磁通门观测数据进行分析,结果表明与周期在几分钟到几小时的极化值一样,5~100 s的磁场极化值Yzh同样具有年变化规律,因此简单的依据极化值Yzh由低值向高值的变化判断是否存在震前电磁辐射异常存在很大的风险。为此,分析了采用富氏拟合技术消除半年以上变化周期的Yzh与台站周边地区地震的关系,表明极化值Yzh高值与其后2个月内台站周边地区地震有很好的对应关系,且大部分地震都发生在1个月内。分析还表明Yzh高值异常持续时间一般为3~5 d,与外空磁场剧烈活动没有关系;单纯采用夜间观测数据不及采用全天观测数据的效果。
This paper did analysis by using the data of fluxgate magnetometer.The result showed that the ratio of the spectral intensities of the vertical to horizontal components of the magnetic field(polarization) of which periods were from 5 to 100 s,same as the polarization of which periods were from several minutes to several hours,also had the annual variation,there would be risk failure when judging whether there were ULF magnetic field anomalies prior to earthquakes only by the variation of the polarization from low value to high value.So the paper applied the fitting of Fourier to remove the relationship between the polarization Yzh of which periods greater than half year and the earthquakes surrounding observation station,and result showed that the high value of the polarization Yzh had a close relationship with the earthquakes which happened in two months after the high value appeared,and most of these earthquakes happened in one month.It was also showed that the duration of precursory of high value was about from one day to five days,and no significant correlation with the geomagnetic activity was found,and there was no advantage using the data at night than that in all day.
This paper did analysis by using the data of fluxgate magnetometer.The result showed that the ratio of the spectral intensities of the vertical to horizontal components of the magnetic field(polarization) of which periods were from 5 to 100 s,same as the polarization of which periods were from several minutes to several hours,also had the annual variation,there would be risk failure when judging whether there were ULF magnetic field anomalies prior to earthquakes only by the variation of the polarization from low value to high value.So the paper applied the fitting of Fourier to remove the relationship between the polarization Yzh of which periods greater than half year and the earthquakes surrounding observation station,and result showed that the high value of the polarization Yzh had a close relationship with the earthquakes which happened in two months after the high value appeared,and most of these earthquakes happened in one month.It was also showed that the duration of precursory of high value was about from one day to five days,and no significant correlation with the geomagnetic activity was found,and there was no advantage using the data at night than that in all day.
引文
[1]张德齐.地震电磁波辐射前兆判据探讨[J].地震学刊,1992,4:1-7.
[2]关华平,刘桂萍.震前电磁辐射异常与地震关系研究[J].地震学报,1995,17(2):237-246.
[3]马钦忠.希腊“VAN”法地电流预报地震介绍[J].地震科技情报,1997,1:5-10.
[4]冯志生,董颂升,王建宇,等.希腊VAN地震预报方法的进展与争论(Ⅰ)-进展[J].国际地震动态,1998,(12),11-17.
[5]Hayakawa M.,Hattori K..Ohta K.Monitoring of ULF(ultra-low-frequency)Geomagnetic Variations Associated with Earthquakes[J].Sensors,2007,7:1108-1122.
[6]杨少峰,杜爱民.新疆喀什地区1996年11月震前超低频电磁辐射异常与震源方向的关系[J].地球物理学报,2002,45(1):101-108.
[7]杨少峰,陈宝生,杜爱民,等.新疆喀什地区地震前地磁脉动异常分析[J].地球物理学报,1998,41(3):332-341.
[8]kopytenko Y.A.,Matiashvili T.G.,Voronov P.M.,et al.Observation of electromagnetic ultralow-frequencylithospheric emissions in caucasian seismically active zone and their connection with earthquakes[M].Tokyo:terra sci.Pub.Comp.,1994.
[9]Hayakawa M.,Kawate R.,Molchanov O.A.,et al.Results of ultra-low-frequency magnetic field measurements during the Guam earthquake of 8 August 1993[J].Geophys Res Lett,1996,23:241-244.
[10]冯志生,梅卫萍,张秀霞,等.中强震前地磁谐波振幅比的趋势性变化特征初步研究[J].西北地震学报,2004,26(1):50-56.
[11]冯志生,居海华,李鸿宇,等.地磁谐波振幅比异常特征的进一步研究及定性解释[J].华南地震,2009,29(1):17-23.
[12]T.Rikitake.Nature of Electromagnetic Emission Precursory to an Earthquake[J].Journal of Geomagnetism and Geoelectricity,1997,49:1153-1163.
[2]关华平,刘桂萍.震前电磁辐射异常与地震关系研究[J].地震学报,1995,17(2):237-246.
[3]马钦忠.希腊“VAN”法地电流预报地震介绍[J].地震科技情报,1997,1:5-10.
[4]冯志生,董颂升,王建宇,等.希腊VAN地震预报方法的进展与争论(Ⅰ)-进展[J].国际地震动态,1998,(12),11-17.
[5]Hayakawa M.,Hattori K..Ohta K.Monitoring of ULF(ultra-low-frequency)Geomagnetic Variations Associated with Earthquakes[J].Sensors,2007,7:1108-1122.
[6]杨少峰,杜爱民.新疆喀什地区1996年11月震前超低频电磁辐射异常与震源方向的关系[J].地球物理学报,2002,45(1):101-108.
[7]杨少峰,陈宝生,杜爱民,等.新疆喀什地区地震前地磁脉动异常分析[J].地球物理学报,1998,41(3):332-341.
[8]kopytenko Y.A.,Matiashvili T.G.,Voronov P.M.,et al.Observation of electromagnetic ultralow-frequencylithospheric emissions in caucasian seismically active zone and their connection with earthquakes[M].Tokyo:terra sci.Pub.Comp.,1994.
[9]Hayakawa M.,Kawate R.,Molchanov O.A.,et al.Results of ultra-low-frequency magnetic field measurements during the Guam earthquake of 8 August 1993[J].Geophys Res Lett,1996,23:241-244.
[10]冯志生,梅卫萍,张秀霞,等.中强震前地磁谐波振幅比的趋势性变化特征初步研究[J].西北地震学报,2004,26(1):50-56.
[11]冯志生,居海华,李鸿宇,等.地磁谐波振幅比异常特征的进一步研究及定性解释[J].华南地震,2009,29(1):17-23.
[12]T.Rikitake.Nature of Electromagnetic Emission Precursory to an Earthquake[J].Journal of Geomagnetism and Geoelectricity,1997,49:1153-1163.
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