2004年印尼8.7级强震前昌黎台的远场电性异常特征探讨
|
摘要
分析了在2004年12月26日印尼8.7级地震前河北昌黎台记录到的自然电位及电场异常,结果显示昌黎台自电位、电场正常时段观测到的半日、半月潮汐波周期变化在震前1个多月发生畸变,周期消失,变化幅度相应减小,震后快速恢复,且潮汐波记录比震前正常时段更加清晰。该台地电阻率的观测结果显示起始下降变化比较平缓,震前一周左右,变化加剧,出现多次阶变。究其原因,在强震发生前断层的蠕滑作用导致孔隙压力变化,产生一种可以在岩石中传播的应变波,由于台站下方岩土层对小应变信号具有很好的放大作用,所以记录到了这种小幅度的应变波,也就是远场的静态应变效应。随着地震临近,应力作用加强,远程应变波引起台站下方水位、水化学性质以及岩石孔隙度、渗透率等的改变,导致电阻率、电场大幅度的阶变,这反映了远场应变波的动态效应。当然就异常幅度而言,应变波的效应还嫌弱一些,因此昌黎台异常变化可能还叠加了震源区激发的电磁波。
In this paper,self-potential and geoelectric field anomalies were analyzed,which were recorded at Changli station of Hebei province before M8.7 Earthquake in Indonesia on Dec.26,2006.The results show that the half-daily and half-monthly tidal wave periodicity changed abnormally about one month before the earthquake,with periodicity disappearing and amplitude reducing,but they recovered after it with clearer state than that at normal time.The observation data of earth resistivity at this station exhibits that it dropped slowly at the beginning,but changed intensely in one week before the earthquake with many times of step-variations.It is found that the formation mechanism might be as follows: the creep-sliding of faults before the strong earthquakes caused local variation of pore pressure,which produced a kind of strain wave propagating in the rock and overlapped with tidal waves,then disturbing the normal records at stations.Due to the better amplification in rock and soil layer beneath Changli station for small stress and strain signals,this wave with small amplitude,i.e.the remote static strain wave,can be recorded here.With the impending of the earthquake and strengthened stress,the remote strain waves resulted in the change beneath the station such as water level,water chemical property and rock porosity,permeability and so on,leading to the large amplitude step-variation in resistivity and geoelectric field,which reflect the dynamic effects of remote strain waves.Of course,the anomaly amplitude of resistivity,the effects of stress wave is not enough,so there may be overlapped anomalous electromagnetic wave from focal area on the electric anomalies recorded at Changli station.
In this paper,self-potential and geoelectric field anomalies were analyzed,which were recorded at Changli station of Hebei province before M8.7 Earthquake in Indonesia on Dec.26,2006.The results show that the half-daily and half-monthly tidal wave periodicity changed abnormally about one month before the earthquake,with periodicity disappearing and amplitude reducing,but they recovered after it with clearer state than that at normal time.The observation data of earth resistivity at this station exhibits that it dropped slowly at the beginning,but changed intensely in one week before the earthquake with many times of step-variations.It is found that the formation mechanism might be as follows: the creep-sliding of faults before the strong earthquakes caused local variation of pore pressure,which produced a kind of strain wave propagating in the rock and overlapped with tidal waves,then disturbing the normal records at stations.Due to the better amplification in rock and soil layer beneath Changli station for small stress and strain signals,this wave with small amplitude,i.e.the remote static strain wave,can be recorded here.With the impending of the earthquake and strengthened stress,the remote strain waves resulted in the change beneath the station such as water level,water chemical property and rock porosity,permeability and so on,leading to the large amplitude step-variation in resistivity and geoelectric field,which reflect the dynamic effects of remote strain waves.Of course,the anomaly amplitude of resistivity,the effects of stress wave is not enough,so there may be overlapped anomalous electromagnetic wave from focal area on the electric anomalies recorded at Changli station.
引文
①明成山等,http://www.cnki.net
[1]Freed A M.Earthquake triggering by static,dynamic,and postseismic stress transfer[J].AnnualReviewof Earth and Planetary Sciences,2005,33:335-367.
[2]高金哲,吕政,张洪艳,等.地震前驱波观测与研究进展[J].华南地震,2005,25(1):53-58.
[3]陈学忠.2004年12月26日印尼8.7级地震及其对我国大陆地震趋势的影响[J].国际地震动态,2005,(1):26-30.
[4]汪成民,尹伯忠.地下水位异常变化[A].国家地震局《一九七六年唐山地震》编辑组,一九七六年唐山地震[C].北京:地震出版社,1982.246-270.
[5]林云芳,曾小平,董玉兰,等.华北和东北地区地磁场变化与大地震的关系[J].地震学报,1988,10(4):396-405.
[6]Zhao Y,Qian F.Geoelectric precursors to strong earthquakes in China[J].Tectonophysics,1994,233:99-113.
[7]Coble R.The effects of the Alaskan earthquake of March 27,1964,on ground water in Lowa[J].Pro Lowa Acad Sci,1965,72:323-332.
[8]Roeloffs E A.Persistent water level changes in a well near Parkfield,CA,due to local and distantearthquake[J].J Geophys Res,1998,103:869-889.
[9]Chia Y Wang,Y S Chiu J J,Liu C W.Changes of groundwater level due to the 1999 Chi~Chiearthquake in the Choshui River alluvial fan in Tai wan[J].Bull Seismol Soc Am,2001,91(5):1062-1068
[10]庄国光.台湾海峡7.3级地震水震波特征研究[J].地震,1999,19(2):199-203.
[11]敬少群,王加卫.长沙井动水位对台湾集集7.6级地震的震时效应及其机理分析[J].华南地震,2001,21(1):32-37.
[12]张子广,万迪堃,董守玉.水震波与地震面波的对比研究及其应用[J].地震,1998,18(4):399-404.
[13]王道.昆仑山口8.1级地震的远程地下水动力学效应[J].内陆地震,2002,16(3):213-223.
[14]冯志生,杨从杰,梅卫萍,等.新沂台地电阻率整点值的远大震前驱波变化[J].地震地磁观测与研究,2003,24(4):9-13.
[15]陈学忠.2004年12月26日印尼8.7级地震及其对我国大陆地震趋势的影响[J].国际地震动态,2005,(1):26-30.
[16]Stein S,Okal E A.Speed and size of the Sumatra earthquake[J].Nature,2005,434,581-582.
[17]梁凯利.2004年12月26日印尼8.7级地震综述[J].国际地震动态,2005,(1):1-5.
[18]陈颙,陈棋福.印尼地震海啸及其相关的地球物理现象[J].地球物理学进展,2005,20(1):112-117.
[19]李国斌.印尼8.7级地震前银川台形变数字化观测资料短临异常特征分析[J].高原地震,2005,17(2):33-37.
[20]郑江蓉,徐桂明,李鸿宇,等.2004年12月26日印尼8.7级强震后江苏地区同震效应分析[J].防震减灾工程学报,2005,25(1):105-113.
[21]曾令森,许志琴,罗立强,等.CCSD在线流体监测捕获的气体地球化学异常与2004年9.3级苏门答腊地震可能的超远程关系[J].岩石学报,2005,21(2):521-524.
[22]张素欣,张子广,张跃刚,等.2004年12月26日印尼大地震河北省数字水位、地温记震能力分析[J].华北地震科学,2005,23(3):27-30.
[23]陆远忠,李胜乐,邓志辉,等.基于GIS的地震分析预报系统[J].四川成都:成都地图出版社,2002.
[24]张学民,王志贤,臧明珍,等.降雨对地电阻率的干扰分析[J].华北地震科学,1996,14(4):71-74.
[25]Ni S,Kanamori H,Hel mberger D.Energy radiation from the Sumatra earthquake[J].Nature,2005,434,582.
[26]Brodsky E E,Roeloffs E,Woodcock D,et al.A mechanismfoe sustained groundwater pressurechanges induced by distant earthquake[J].J Geophys Res,2003,108:2390.
[27]国家地震局预测预防司.电磁学分析预报方法[M].北京:地震出版社,1998.32-33.
[28]马占虎,杜学彬,谭大成,等.地震电性变化及其物理机制初步讨论[J].西北地震学报,2004,26(3):234-239.
[29]Yamazaki Y.Electrical conductivity of strained rocks,1,Laboratory experi ments on sedi mentaryrocks[J].Bull Earthquake Inst Univ Tokyo,1965,43,783-802.
[30]藤森义彦.岩石の歪とと电导率变化[M].Conductivity Anomaly,1982.199-207.
[31]Morrow C,WF Brace.Electrical resistivity changes in tuffs due to stress[J].J Geophy Res,1981,86,2929-2934.
[32]陆阳泉,等.岩石电阻率与应变关系的实验研究[A].中国地震局.地震预报方法实用化文集地磁地电专辑[C].北京:学术书刊出版社,1990.343-350.
[33]赵玉林,钱复业,许同春.受力条件下岩(土)层电阻率变化的放大系数及其与应变关系的研究[A].国家地震局.地震预报方法实用化文集地磁地电专辑[C].北京:学术书刊出版社,1990.334-342.
[34]陈有发,马钦忠,张杰,等.震前自然电场的前兆及其可能机理[J].华南地震,1999,19(3):26-34.
[35]王敏,张培震,沈正康,等.全球定位系统(GPS)测定的印尼苏门答腊地震的远场同震地表位移[J].科学通报,2006,51(3):365-368.
[36]韩渭宾.印尼苏门答腊西8.7级地震的几个特点及由其引发的一些思考[J].四川地震,2005,19(1):2-5.
[37]张学民,郭建芳,郭学增.河北省数字地电场数据分析[J].中国地震,2006,22(1):64-75.
[38]熊皓.电磁波传播与空间环境[J].北京:电子工业出版社,2004.
[39]Gaffet S,Gugliel mi Y,Virieux J,et al.Si multaneous seismic and magnetic measurements in theLow-Noise Underground Laboratory(LSBB)of Rustrel,France,during the 2001 Juanuary 26 Indi-an earthquake[J].Geophys J Int,2003,155:981-990.
[1]Freed A M.Earthquake triggering by static,dynamic,and postseismic stress transfer[J].AnnualReviewof Earth and Planetary Sciences,2005,33:335-367.
[2]高金哲,吕政,张洪艳,等.地震前驱波观测与研究进展[J].华南地震,2005,25(1):53-58.
[3]陈学忠.2004年12月26日印尼8.7级地震及其对我国大陆地震趋势的影响[J].国际地震动态,2005,(1):26-30.
[4]汪成民,尹伯忠.地下水位异常变化[A].国家地震局《一九七六年唐山地震》编辑组,一九七六年唐山地震[C].北京:地震出版社,1982.246-270.
[5]林云芳,曾小平,董玉兰,等.华北和东北地区地磁场变化与大地震的关系[J].地震学报,1988,10(4):396-405.
[6]Zhao Y,Qian F.Geoelectric precursors to strong earthquakes in China[J].Tectonophysics,1994,233:99-113.
[7]Coble R.The effects of the Alaskan earthquake of March 27,1964,on ground water in Lowa[J].Pro Lowa Acad Sci,1965,72:323-332.
[8]Roeloffs E A.Persistent water level changes in a well near Parkfield,CA,due to local and distantearthquake[J].J Geophys Res,1998,103:869-889.
[9]Chia Y Wang,Y S Chiu J J,Liu C W.Changes of groundwater level due to the 1999 Chi~Chiearthquake in the Choshui River alluvial fan in Tai wan[J].Bull Seismol Soc Am,2001,91(5):1062-1068
[10]庄国光.台湾海峡7.3级地震水震波特征研究[J].地震,1999,19(2):199-203.
[11]敬少群,王加卫.长沙井动水位对台湾集集7.6级地震的震时效应及其机理分析[J].华南地震,2001,21(1):32-37.
[12]张子广,万迪堃,董守玉.水震波与地震面波的对比研究及其应用[J].地震,1998,18(4):399-404.
[13]王道.昆仑山口8.1级地震的远程地下水动力学效应[J].内陆地震,2002,16(3):213-223.
[14]冯志生,杨从杰,梅卫萍,等.新沂台地电阻率整点值的远大震前驱波变化[J].地震地磁观测与研究,2003,24(4):9-13.
[15]陈学忠.2004年12月26日印尼8.7级地震及其对我国大陆地震趋势的影响[J].国际地震动态,2005,(1):26-30.
[16]Stein S,Okal E A.Speed and size of the Sumatra earthquake[J].Nature,2005,434,581-582.
[17]梁凯利.2004年12月26日印尼8.7级地震综述[J].国际地震动态,2005,(1):1-5.
[18]陈颙,陈棋福.印尼地震海啸及其相关的地球物理现象[J].地球物理学进展,2005,20(1):112-117.
[19]李国斌.印尼8.7级地震前银川台形变数字化观测资料短临异常特征分析[J].高原地震,2005,17(2):33-37.
[20]郑江蓉,徐桂明,李鸿宇,等.2004年12月26日印尼8.7级强震后江苏地区同震效应分析[J].防震减灾工程学报,2005,25(1):105-113.
[21]曾令森,许志琴,罗立强,等.CCSD在线流体监测捕获的气体地球化学异常与2004年9.3级苏门答腊地震可能的超远程关系[J].岩石学报,2005,21(2):521-524.
[22]张素欣,张子广,张跃刚,等.2004年12月26日印尼大地震河北省数字水位、地温记震能力分析[J].华北地震科学,2005,23(3):27-30.
[23]陆远忠,李胜乐,邓志辉,等.基于GIS的地震分析预报系统[J].四川成都:成都地图出版社,2002.
[24]张学民,王志贤,臧明珍,等.降雨对地电阻率的干扰分析[J].华北地震科学,1996,14(4):71-74.
[25]Ni S,Kanamori H,Hel mberger D.Energy radiation from the Sumatra earthquake[J].Nature,2005,434,582.
[26]Brodsky E E,Roeloffs E,Woodcock D,et al.A mechanismfoe sustained groundwater pressurechanges induced by distant earthquake[J].J Geophys Res,2003,108:2390.
[27]国家地震局预测预防司.电磁学分析预报方法[M].北京:地震出版社,1998.32-33.
[28]马占虎,杜学彬,谭大成,等.地震电性变化及其物理机制初步讨论[J].西北地震学报,2004,26(3):234-239.
[29]Yamazaki Y.Electrical conductivity of strained rocks,1,Laboratory experi ments on sedi mentaryrocks[J].Bull Earthquake Inst Univ Tokyo,1965,43,783-802.
[30]藤森义彦.岩石の歪とと电导率变化[M].Conductivity Anomaly,1982.199-207.
[31]Morrow C,WF Brace.Electrical resistivity changes in tuffs due to stress[J].J Geophy Res,1981,86,2929-2934.
[32]陆阳泉,等.岩石电阻率与应变关系的实验研究[A].中国地震局.地震预报方法实用化文集地磁地电专辑[C].北京:学术书刊出版社,1990.343-350.
[33]赵玉林,钱复业,许同春.受力条件下岩(土)层电阻率变化的放大系数及其与应变关系的研究[A].国家地震局.地震预报方法实用化文集地磁地电专辑[C].北京:学术书刊出版社,1990.334-342.
[34]陈有发,马钦忠,张杰,等.震前自然电场的前兆及其可能机理[J].华南地震,1999,19(3):26-34.
[35]王敏,张培震,沈正康,等.全球定位系统(GPS)测定的印尼苏门答腊地震的远场同震地表位移[J].科学通报,2006,51(3):365-368.
[36]韩渭宾.印尼苏门答腊西8.7级地震的几个特点及由其引发的一些思考[J].四川地震,2005,19(1):2-5.
[37]张学民,郭建芳,郭学增.河北省数字地电场数据分析[J].中国地震,2006,22(1):64-75.
[38]熊皓.电磁波传播与空间环境[J].北京:电子工业出版社,2004.
[39]Gaffet S,Gugliel mi Y,Virieux J,et al.Si multaneous seismic and magnetic measurements in theLow-Noise Underground Laboratory(LSBB)of Rustrel,France,during the 2001 Juanuary 26 Indi-an earthquake[J].Geophys J Int,2003,155:981-990.
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心