地壳应变场对气压短周期变化的响应
|
摘要
大气压力变化可分为由日、月引力和太阳热辐射产生的潮汐变化和非潮汐频段的短周期气压变化,其引起的地壳应变可达10-9量级.我们选用分钟采样的观测精度达10-9量级的钻孔应变仪,对山东省泰安台2002~2005年气压及体应变分钟值资料进行深入分析,研究了地壳应变场对短周期气压变化的响应规律.频谱分析结果表明,短周期气压变化对体应变的影响主要集中在周期大于2000 s的低频段.利用小波分解方法,得出了短周期气压系数随不同频段和不同时间的变化规律:高频段(周期小于960 s)气压系数数值较小,随频率变化幅度较大;低频段(周期大于960 s)气压系数数值较大,但变化趋于平稳;在频段一定的情况下,短周期气压系数随时间变化较平稳.从钻孔应变仪观测原理和按余弦函数分布的载荷作用于地壳表面的应力解出发,得出了地壳不同深度对不同频率短周期气压场的响应,理论计算与实际观测基本相符.研究结果表明,短周期气压变化对低频信号(周期大于2000 s)的影响较大,提取低频地球自由振荡信号时要消除气压影响,对苏门答腊大地震激发的地球球型自由振荡的功率谱分析验证了这一结论.
Atmospheric pressures,which can produce crustal strain of 10-9,can be divided into atmospheric tides and short-period variations.Borehole strain observations with minute sampling at the Tai'an observation station,Shan-Dong province from 2002 to 2005 are applied to analyze the response rule of the crustal strain field to short-period atmospheric pressure variations.Spectrum analysis shows short-period atmospheric pressure variations can influence low-frequency volume strain observations(periods are greater than 2000s).Wavelet transform is used to obtain the short-period atmospheric pressure variation rule with different frequencies and different times.High-frequency atmospheric pressure coefficients,whose periods are less than 960s,are small,but variation ranges are large.Low-frequency atmospheric pressure coefficients(period greater than 960s) are large,but variation ranges are small.Atmospheric pressure coefficients with certain frequencies change reposefully.Based on the borehole strainmeter design principle and elasticity mechanics theory in which stress is distributed as a cosine function,we obtain the response rule of crust at different depth to different frequency short-period atmospheric pressure variations.Theoretical calculation is coincident with the observation curve.Research results show short-period atmospheric pressure variations can influence low-frequency signals(period greater than 2000s),thus atmospheric pressure variations must be removed when earth free oscillation signals being extracted.Earth free oscillations excited by the great Sumatra earthquake occurred on December 26,2004 that we extracted testify this conclusion.
Atmospheric pressures,which can produce crustal strain of 10-9,can be divided into atmospheric tides and short-period variations.Borehole strain observations with minute sampling at the Tai'an observation station,Shan-Dong province from 2002 to 2005 are applied to analyze the response rule of the crustal strain field to short-period atmospheric pressure variations.Spectrum analysis shows short-period atmospheric pressure variations can influence low-frequency volume strain observations(periods are greater than 2000s).Wavelet transform is used to obtain the short-period atmospheric pressure variation rule with different frequencies and different times.High-frequency atmospheric pressure coefficients,whose periods are less than 960s,are small,but variation ranges are large.Low-frequency atmospheric pressure coefficients(period greater than 960s) are large,but variation ranges are small.Atmospheric pressure coefficients with certain frequencies change reposefully.Based on the borehole strainmeter design principle and elasticity mechanics theory in which stress is distributed as a cosine function,we obtain the response rule of crust at different depth to different frequency short-period atmospheric pressure variations.Theoretical calculation is coincident with the observation curve.Research results show short-period atmospheric pressure variations can influence low-frequency signals(period greater than 2000s),thus atmospheric pressure variations must be removed when earth free oscillation signals being extracted.Earth free oscillations excited by the great Sumatra earthquake occurred on December 26,2004 that we extracted testify this conclusion.
引文
[1]张学阳.潮汐观测中高精度气压辅助观测的必要性及气压效应的校正[J].地壳形变与地震,1987,4(4):273~280.Zhang X Y.A necessity of high-precise assistance measurementfor atmospheric pressure and correction of atmospheric pres-sure effect in tidal observation[J].Crustal deformation andearthquake(in Chinese),1987,4(4):273~280.
[2]邱泽华,马谨,池顺良,等.钻孔差应变仪观测的苏门答腊大地震激发的地球环形自由震荡[J].地球物理学报,2007,50(3):797~805.Qiu Z H,Ma J,Chi S L,et al.Earth’s free torsional oscilla-tions of the great sumatra earthquake observed with boreholeshear strainmeter[J].Chinese J.Geophys.(in Chinese),2007,50(3):797~805.
[3]唐磊,邱泽华,阚宝祥.中国钻孔体应变台网观测到的地球球型振荡[J].大地测量与地球动力学,2007,27(6):37~44.Tang L,Qiu Z H,Kan B X.earth’s spheroidal oscillations ob-served with China borehole dilatometer network[J].Journal ofgeodesy and geodynamics(in Chinese),2007,27(6):37~44
[4]杜品仁.气压变化及其对地壳变形和深井水位的影响[J].地球物理学报,1991,34(1):73~81.Du P R.barometric pressure variations and their influence onthe crust’s deformations and water level in deep well[J].AC-TA GEOPHYSICA SINICA(in Chinese),1991,34(1),73~81.
[5]Savino,John,K.McKamy,Hade G.Structures in earth noisebeyond twenty seconds—a window for earthquakes[J].Bull.Seism.Soc.Am.,1972,62,141~176.
[6]薄万举.分频段排干扰方法的建立与应用[J].山西地震,1993,(3):24~29.Bo W J.Development and Application of the Eliminating inter-ference method by frequency—band Division[J].Earthquakeresearch in Shanxi(in Chinese),1993,(3):24~29.
[7]张凌空.体应变观测中的气压干扰机制和排除方法的研究[J].地震,1996,16(2):144~152.Zhang L K.Study on mechanism of atmospheric pressure jam-ming in the volume strain observation and the method for elim-inating the jamming[J].Earthquake(in Chinese),1996,16(2):144~151.
[8]王梅.数字化体应变与气压、水位相关性研究[J].大地测量与地球动力学,2002,22(4):85~88.Wang M.Study on correlation of digital body strain data withatmosphere and well water level[J].Journal of geodesy andgeodynamics(in Chinese),2002,22(4):85~88.
[9]王梅,李峰,孔向阳,等.数字化形变观测干扰识别[J].大地测量与地球动力学,2004,24(1):94~98.Wang M,Li F,Kong X Y,et al.Identification of disturbance ofdigital deformation observations,Journal of geodesy and geo-dynamics(in Chinese),2004,24(1):94~98.
[10]王梅,毛玉华,李峰.体应变与水位、气压相关系数变化规律的研究[J].地壳构造与地壳应力文集,2006,18:125~130.Wang M,Mao Y H,Li F.A study on the correlation coefficient ofbody-strain meter data with water level and air pressure.Crustalstructure and stress(in Chinese),2006,18:125~130.
[11]李杰,刘敏,、邹钟毅,等.数字化钻孔体应变干扰机理及异常分析[J].地震研究,2003,26(3):230~237.Li J,Liu M,Zhou Z Y,et al.Analysis of Disturbance mech-anism and abnormity of digital observation data of boreholebody strain meters.Journal of seismological research,2003,26(3):230~237.
[12]李杰,邹钟毅,闫德桥,等.TJ一Ⅱ型钻孔体应变仪数字化观测资料分析[J].大地测量与地球动力学,2002,22(3):69~74.Li J,Zhou Z Y,,Yan D Q,et al.Analysis of digitized observa-tions of TJ-Ⅱborehole body strain meters[J].Journal of geodesyand geodynamics(in Chinese),2002,22(3):69~74.
[13]高福旺,李丽,牛安福,等.对体应变干扰因素的识别与排除[J].地震,2004,24(增刊):90~97.Gao S W,Li L,Niu A F,et al.Study on the identificationand elimination of the disturbance in crustal strain record[J].earthquake(in Chinese),2004,24(Supp1):90~97.
[14]殷积涛、汪成民.承压含水层的荷载效应和井孔水位的气压效应[J].中国地震,1988,4(2):39~48.Yin J T,Wang C M.Loading effect on confined aquifer andbarometric effect on water level in wells[J].Earthquake inChina(in Chinese),1988,4(2):39~48.
[15]张昭栋、段会川、王昌文等.一种计算井水位气压系数、固体潮系数和海潮系数的新方法[J],地震,1991,(6):48~53.Zhang Z D,Duan H C,Wang C W.A new method for calcu-lating barometric.Solid tide and seatide coefficients of welllevel.earthquake(in Chinese),1991,(6):48~53.
[16]Sorrells G G,McDonald J A,Der Z A,Eugene H.Earthmotion caused by local atmospheric pressure changes[J].Geophys.J.,1971,26:83~98.
[17]Herron T J,Tolstoy I.Tracking jet-stream winds fromground-level pressure signals.J.Atmospheric Sci.,1969,26(2):266~269.
[18]李杰,刘希强,李红,等.利用小波变换方法分析形变观测资料的正常背景变化特征[J].地震学报,2005,27(1):33~41.Li J,Liu X Q,Li H,et al.Analyses on normal backgroundcharacteristics about deformation observation data on the ba-sis of wavelet transform method[J].Acta Seismologica Sinica(in chinese),2005,27(1):33~41.
[19]Sorrells,Gordon G.Low-frequency earth motion generatedby slowly propagating partially organized pressure fields[J].Bull.Seism.Soc.Am.,1972,62:141~176.
[20]Sorrells,Gordon G.A preliminary investigation into the rela-tionship between long-period noise and local fluctuations inthe atmospheric pressure field[J].Geophys.J.,1971,26:71~82.
[21]Herron T J,Tolstoy I,Kraft D W.Atmospheric pressurebackground fluctuations in the mesoscale range[J].J.Geo-phys.Res.1969,74:1321~1329.
[22]Evertson D W.Borehole strainmeters for seismology,Rep.ARL-TR-77-62,Applied Research Lab.,University of Tex-as,Austin,Texas.1977.
[23]Lumley J L,Panofsky H L.The structure of atmospheric tur-bulence[J].Wiley,New York,1964,239.
[24]Fung Y C.“Foundation of Solid Mechanics”[M].PrenticeHall,Englewood Cliffs,1965.
[25]Sacks I S.Evertson D W,Dorman L M.“Borehole strainme-ters”[M]Carnegie Institution Yearbook 68.Washington,D.C.,1971.
[26]苏恺之,李海亮,张钧,等.钻孔地应变观测新进展[M].北京:地震出版社,2003.SU K Z,Li H L,Zhang J,et al.New development of bore-hole strain observation(in Chinese)[M].Beijing:seismologi-cal Press,2003.
[27]傅承义,陈运泰,祁贵仲.地球物理学基础[M].北京:科学出版社,1985.Fu C Y,Chen Y T,Qi G Z.Fundamental Geophysics(inChinese)[M].Beijing:Science Press,1985.
[2]邱泽华,马谨,池顺良,等.钻孔差应变仪观测的苏门答腊大地震激发的地球环形自由震荡[J].地球物理学报,2007,50(3):797~805.Qiu Z H,Ma J,Chi S L,et al.Earth’s free torsional oscilla-tions of the great sumatra earthquake observed with boreholeshear strainmeter[J].Chinese J.Geophys.(in Chinese),2007,50(3):797~805.
[3]唐磊,邱泽华,阚宝祥.中国钻孔体应变台网观测到的地球球型振荡[J].大地测量与地球动力学,2007,27(6):37~44.Tang L,Qiu Z H,Kan B X.earth’s spheroidal oscillations ob-served with China borehole dilatometer network[J].Journal ofgeodesy and geodynamics(in Chinese),2007,27(6):37~44
[4]杜品仁.气压变化及其对地壳变形和深井水位的影响[J].地球物理学报,1991,34(1):73~81.Du P R.barometric pressure variations and their influence onthe crust’s deformations and water level in deep well[J].AC-TA GEOPHYSICA SINICA(in Chinese),1991,34(1),73~81.
[5]Savino,John,K.McKamy,Hade G.Structures in earth noisebeyond twenty seconds—a window for earthquakes[J].Bull.Seism.Soc.Am.,1972,62,141~176.
[6]薄万举.分频段排干扰方法的建立与应用[J].山西地震,1993,(3):24~29.Bo W J.Development and Application of the Eliminating inter-ference method by frequency—band Division[J].Earthquakeresearch in Shanxi(in Chinese),1993,(3):24~29.
[7]张凌空.体应变观测中的气压干扰机制和排除方法的研究[J].地震,1996,16(2):144~152.Zhang L K.Study on mechanism of atmospheric pressure jam-ming in the volume strain observation and the method for elim-inating the jamming[J].Earthquake(in Chinese),1996,16(2):144~151.
[8]王梅.数字化体应变与气压、水位相关性研究[J].大地测量与地球动力学,2002,22(4):85~88.Wang M.Study on correlation of digital body strain data withatmosphere and well water level[J].Journal of geodesy andgeodynamics(in Chinese),2002,22(4):85~88.
[9]王梅,李峰,孔向阳,等.数字化形变观测干扰识别[J].大地测量与地球动力学,2004,24(1):94~98.Wang M,Li F,Kong X Y,et al.Identification of disturbance ofdigital deformation observations,Journal of geodesy and geo-dynamics(in Chinese),2004,24(1):94~98.
[10]王梅,毛玉华,李峰.体应变与水位、气压相关系数变化规律的研究[J].地壳构造与地壳应力文集,2006,18:125~130.Wang M,Mao Y H,Li F.A study on the correlation coefficient ofbody-strain meter data with water level and air pressure.Crustalstructure and stress(in Chinese),2006,18:125~130.
[11]李杰,刘敏,、邹钟毅,等.数字化钻孔体应变干扰机理及异常分析[J].地震研究,2003,26(3):230~237.Li J,Liu M,Zhou Z Y,et al.Analysis of Disturbance mech-anism and abnormity of digital observation data of boreholebody strain meters.Journal of seismological research,2003,26(3):230~237.
[12]李杰,邹钟毅,闫德桥,等.TJ一Ⅱ型钻孔体应变仪数字化观测资料分析[J].大地测量与地球动力学,2002,22(3):69~74.Li J,Zhou Z Y,,Yan D Q,et al.Analysis of digitized observa-tions of TJ-Ⅱborehole body strain meters[J].Journal of geodesyand geodynamics(in Chinese),2002,22(3):69~74.
[13]高福旺,李丽,牛安福,等.对体应变干扰因素的识别与排除[J].地震,2004,24(增刊):90~97.Gao S W,Li L,Niu A F,et al.Study on the identificationand elimination of the disturbance in crustal strain record[J].earthquake(in Chinese),2004,24(Supp1):90~97.
[14]殷积涛、汪成民.承压含水层的荷载效应和井孔水位的气压效应[J].中国地震,1988,4(2):39~48.Yin J T,Wang C M.Loading effect on confined aquifer andbarometric effect on water level in wells[J].Earthquake inChina(in Chinese),1988,4(2):39~48.
[15]张昭栋、段会川、王昌文等.一种计算井水位气压系数、固体潮系数和海潮系数的新方法[J],地震,1991,(6):48~53.Zhang Z D,Duan H C,Wang C W.A new method for calcu-lating barometric.Solid tide and seatide coefficients of welllevel.earthquake(in Chinese),1991,(6):48~53.
[16]Sorrells G G,McDonald J A,Der Z A,Eugene H.Earthmotion caused by local atmospheric pressure changes[J].Geophys.J.,1971,26:83~98.
[17]Herron T J,Tolstoy I.Tracking jet-stream winds fromground-level pressure signals.J.Atmospheric Sci.,1969,26(2):266~269.
[18]李杰,刘希强,李红,等.利用小波变换方法分析形变观测资料的正常背景变化特征[J].地震学报,2005,27(1):33~41.Li J,Liu X Q,Li H,et al.Analyses on normal backgroundcharacteristics about deformation observation data on the ba-sis of wavelet transform method[J].Acta Seismologica Sinica(in chinese),2005,27(1):33~41.
[19]Sorrells,Gordon G.Low-frequency earth motion generatedby slowly propagating partially organized pressure fields[J].Bull.Seism.Soc.Am.,1972,62:141~176.
[20]Sorrells,Gordon G.A preliminary investigation into the rela-tionship between long-period noise and local fluctuations inthe atmospheric pressure field[J].Geophys.J.,1971,26:71~82.
[21]Herron T J,Tolstoy I,Kraft D W.Atmospheric pressurebackground fluctuations in the mesoscale range[J].J.Geo-phys.Res.1969,74:1321~1329.
[22]Evertson D W.Borehole strainmeters for seismology,Rep.ARL-TR-77-62,Applied Research Lab.,University of Tex-as,Austin,Texas.1977.
[23]Lumley J L,Panofsky H L.The structure of atmospheric tur-bulence[J].Wiley,New York,1964,239.
[24]Fung Y C.“Foundation of Solid Mechanics”[M].PrenticeHall,Englewood Cliffs,1965.
[25]Sacks I S.Evertson D W,Dorman L M.“Borehole strainme-ters”[M]Carnegie Institution Yearbook 68.Washington,D.C.,1971.
[26]苏恺之,李海亮,张钧,等.钻孔地应变观测新进展[M].北京:地震出版社,2003.SU K Z,Li H L,Zhang J,et al.New development of bore-hole strain observation(in Chinese)[M].Beijing:seismologi-cal Press,2003.
[27]傅承义,陈运泰,祁贵仲.地球物理学基础[M].北京:科学出版社,1985.Fu C Y,Chen Y T,Qi G Z.Fundamental Geophysics(inChinese)[M].Beijing:Science Press,1985.
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