汶川大地震前的重力扰动
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摘要
继1997年5月采用LacosteET-21重力仪在中国南极中山站观测发现South of Kermadec Islands 7.1级地震前的"重力扰动"现象之后,2008年5月又在武汉大地测量国家野外科学观测站LacosteET-20重力仪的观测资料中发现了汶川大地震的"重力扰动"现象:从大震前两天开始,"重力扰动"逐渐增大、最大振幅约为±0.8×10-8ms-2,直到大震发生。由于这两次监测的时间不同、地点不同、仪器不同(ET-21与ET-20),这就使得监测结果的可靠性得到了加强。初步认识是:在某些强震发生前两天左右,往往会出现较明显的"重力扰动",其振幅在±(1~2)×10-8ms-2左右、信号周期4~8s。
After having deserved the significant gravity disturbance before the Kermadec Islands earthquake(Mw 7.1) on May 27,1997 at Zhongshan station in Antarctica with LacosteET-21 gravimeter,and observed the similar disturbance before the Wenchuan earthquake(Ms 8.0) on May 12,2008 at the Wuhan National Field Scientific Observation Station for Geodesy with LacosteET-20 gravimeter.The analysis of the gravity data of the Wenchuan earthquake shows that the gravity disturbance had been gradually increasing since two days before the earthquake with the maximum amplitude of about 0.8×10-8ms-2.The observations of gravity disturbance before earthquake are reliable,as the anomaly was observed at different sites with different Lacoste-ET gravimeters.It is concluded that the significant gravity disturbance appear usually about two days before some strong earthquakes with the amplitude of(1~2)×10-8ms-2 and the period of 4-8 s.
After having deserved the significant gravity disturbance before the Kermadec Islands earthquake(Mw 7.1) on May 27,1997 at Zhongshan station in Antarctica with LacosteET-21 gravimeter,and observed the similar disturbance before the Wenchuan earthquake(Ms 8.0) on May 12,2008 at the Wuhan National Field Scientific Observation Station for Geodesy with LacosteET-20 gravimeter.The analysis of the gravity data of the Wenchuan earthquake shows that the gravity disturbance had been gradually increasing since two days before the earthquake with the maximum amplitude of about 0.8×10-8ms-2.The observations of gravity disturbance before earthquake are reliable,as the anomaly was observed at different sites with different Lacoste-ET gravimeters.It is concluded that the significant gravity disturbance appear usually about two days before some strong earthquakes with the amplitude of(1~2)×10-8ms-2 and the period of 4-8 s.
引文
1 Chandler S C.On the variation of latitude[J].AstronomicalJournal,1891,11:83.
2 Benioff H.Long waves observed in the Kamchatka earth-quake of November 4,1952[J].J.Geophy.Res.,1958,63.
3郝晓光.L&R-ET重力仪在南极中山站记录到“不明地学事件”[J].极地研究,1997,9(3):214-215.3 Hao Xiaoguang.An unidentified geophysical event recordedwith L&R-ET gravity meter at Zhongshan Station Antarctica[J].Chinese Polar Science,1997,8(2):146-147.
4郝晓光,等.重力高频扰动与地震[J].地壳形变与地震,2001,21(3):9-13.4 Hao Xiaoguang,et al.Gravity high-frequency disturbanceand occurrence of earthquake[J].Crustal Deformation andEarthquake,2001,21(3):9-13.(in Chinese)
5朱传镇,房明山,安镇文.脉动与地震关系初步探讨[J].地球物理学报,1977,20(1):20-32.5 Zhu Chuanzhen,Fang Mingshan and An Zhenwen.Prelimi-nary discuss on relationship between disturbance and earth-quake[J].Chinese Journal of Geophysics,1977,20(1):20-32.(in Chinese)
6韩元杰.预滑与地震———长周期波动研究[J].西北地震学报,1984,6(1):10-15.6 Han Yuanjie.Study on pre-slip precursor of the earth-quake———long period precursory seismic wave[J].North-western Seismological Journal,1984,6(1):10-15.(inChinese)
7冯德益,等.长周期形变波及其所反应的短期和临震地震前兆[J].地震学报,1984,6(1):41-56.7 Feng Deyi,et al.Long-period deformational waves andshort-term and imminent earthquake precursors[J].ActaSeismologica Sinica,1984,6(1):41-56.(in Chinese)
8陈德福,罗荣祥,刘国培:倾斜异常图像分类及其特征浅析[J].地震学报,1986,8(2):211-225.8 Chen Defu,Luo Rongxiang and Liu Guopei.Preliminary o-pinion on the features and classification of anomaly patternsof crustal tilt[J].Acta Seismologica Sinica,1986,8(2):211-225.(in Chinese)
9姚同福,等.1976年松潘7.2级地震前几种异常波形的记录特征及其在大震短临预报中的应用[J].西北地震学报,1994,16(2):57-61.9 Yao Tongfu,et al.Waveform anomaly prior to the Songpanearthquake and its value to short-imminent prediction ofstrong earthquakes[J].Northwestern Seismological Journal,1994,16(2):57-61.(in Chinese)
10张晓东,马文静.1994年2月16日共和5.8级地震短临预报实况[J].地震,1995(1):20-28.10 Zhang Xiaodong and Ma Wenjing.The short-term and im-pending earthquake prediction for Gonghe earthquake withMs5.8 on Feb.16 1994[J].Earthquake,1995(1):20-28.(in Chinese)
11 Dziewonski A M and F Gilbert.Temporal variation of theseismic moment tensor and evidence of precursive compres-sion for two deep earthquakes[J].Nature,1974,247:185-188.
12 Kanamori J and J J Cipar.Focal process of the great Chil-ean earthquake May 22,1960[J].Phys.Earth.Planet.Inter,1974,9:128-136.
13 Kerr R.Quake prediction by seismic oxymora?[J].Sci-ence,1990,248:1490.
14 Ihmle P F,Harabaglia P and Jordan T H.Teleseismic de-tection of slowprecursors of thegreat1989 Macquarie Ridgeearthquake[J].Science,1994,261:177-183.
15 Ihmle P F and Jordan TH.Teleseismic search for slowpre-cursors to large earthquake[J].Science,1994,266:1 547-1 551.
16 Monastersky R.Before the quake:Detecting the slowgroan[J].Science News,1994,146(23):374.
17 McGuire J J and Ihmle P F.Time-domain observations ofa slow precursor to the 1994 Roman the transform earth-quake[J].Science,1996,273:82-85.
18 Kerr R.Seismology:A slowstart for earthquakes[J].Sci-ence,1998,279:985.
19 Kizawa T.大地震前后重力仪的记录[J].国外地震,1972,1:39-41.19 Kizawa T.Recording of gravimeter around strong earth-quake[J].Oversea Earthquakes,1972,1:39-41.(inChinese)
20 Kanamori Hand Cipar J J.Focal process of the great Chil-ean earthquake May 22,1960[J].Physics of the Earthand Planetary Interiors,1974,9:128-136.
2 Benioff H.Long waves observed in the Kamchatka earth-quake of November 4,1952[J].J.Geophy.Res.,1958,63.
3郝晓光.L&R-ET重力仪在南极中山站记录到“不明地学事件”[J].极地研究,1997,9(3):214-215.3 Hao Xiaoguang.An unidentified geophysical event recordedwith L&R-ET gravity meter at Zhongshan Station Antarctica[J].Chinese Polar Science,1997,8(2):146-147.
4郝晓光,等.重力高频扰动与地震[J].地壳形变与地震,2001,21(3):9-13.4 Hao Xiaoguang,et al.Gravity high-frequency disturbanceand occurrence of earthquake[J].Crustal Deformation andEarthquake,2001,21(3):9-13.(in Chinese)
5朱传镇,房明山,安镇文.脉动与地震关系初步探讨[J].地球物理学报,1977,20(1):20-32.5 Zhu Chuanzhen,Fang Mingshan and An Zhenwen.Prelimi-nary discuss on relationship between disturbance and earth-quake[J].Chinese Journal of Geophysics,1977,20(1):20-32.(in Chinese)
6韩元杰.预滑与地震———长周期波动研究[J].西北地震学报,1984,6(1):10-15.6 Han Yuanjie.Study on pre-slip precursor of the earth-quake———long period precursory seismic wave[J].North-western Seismological Journal,1984,6(1):10-15.(inChinese)
7冯德益,等.长周期形变波及其所反应的短期和临震地震前兆[J].地震学报,1984,6(1):41-56.7 Feng Deyi,et al.Long-period deformational waves andshort-term and imminent earthquake precursors[J].ActaSeismologica Sinica,1984,6(1):41-56.(in Chinese)
8陈德福,罗荣祥,刘国培:倾斜异常图像分类及其特征浅析[J].地震学报,1986,8(2):211-225.8 Chen Defu,Luo Rongxiang and Liu Guopei.Preliminary o-pinion on the features and classification of anomaly patternsof crustal tilt[J].Acta Seismologica Sinica,1986,8(2):211-225.(in Chinese)
9姚同福,等.1976年松潘7.2级地震前几种异常波形的记录特征及其在大震短临预报中的应用[J].西北地震学报,1994,16(2):57-61.9 Yao Tongfu,et al.Waveform anomaly prior to the Songpanearthquake and its value to short-imminent prediction ofstrong earthquakes[J].Northwestern Seismological Journal,1994,16(2):57-61.(in Chinese)
10张晓东,马文静.1994年2月16日共和5.8级地震短临预报实况[J].地震,1995(1):20-28.10 Zhang Xiaodong and Ma Wenjing.The short-term and im-pending earthquake prediction for Gonghe earthquake withMs5.8 on Feb.16 1994[J].Earthquake,1995(1):20-28.(in Chinese)
11 Dziewonski A M and F Gilbert.Temporal variation of theseismic moment tensor and evidence of precursive compres-sion for two deep earthquakes[J].Nature,1974,247:185-188.
12 Kanamori J and J J Cipar.Focal process of the great Chil-ean earthquake May 22,1960[J].Phys.Earth.Planet.Inter,1974,9:128-136.
13 Kerr R.Quake prediction by seismic oxymora?[J].Sci-ence,1990,248:1490.
14 Ihmle P F,Harabaglia P and Jordan T H.Teleseismic de-tection of slowprecursors of thegreat1989 Macquarie Ridgeearthquake[J].Science,1994,261:177-183.
15 Ihmle P F and Jordan TH.Teleseismic search for slowpre-cursors to large earthquake[J].Science,1994,266:1 547-1 551.
16 Monastersky R.Before the quake:Detecting the slowgroan[J].Science News,1994,146(23):374.
17 McGuire J J and Ihmle P F.Time-domain observations ofa slow precursor to the 1994 Roman the transform earth-quake[J].Science,1996,273:82-85.
18 Kerr R.Seismology:A slowstart for earthquakes[J].Sci-ence,1998,279:985.
19 Kizawa T.大地震前后重力仪的记录[J].国外地震,1972,1:39-41.19 Kizawa T.Recording of gravimeter around strong earth-quake[J].Oversea Earthquakes,1972,1:39-41.(inChinese)
20 Kanamori Hand Cipar J J.Focal process of the great Chil-ean earthquake May 22,1960[J].Physics of the Earthand Planetary Interiors,1974,9:128-136.
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