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国家地震局地质研究所在四川省西昌市邛海建成遥测地倾斜网并于1986年9月正式通过验收。 遥测地倾斜测网是观测地形变的一种新方法。它的工作原理与连通管倾斜仪一致,即根据两端仪表部分的液面升降确定相对地壳垂直形变量和倾斜方向。遥测地倾斜测网则是利用观测湖泊水平面的升降确定地壳的相对垂直形变量和倾斜方向 相似文献
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施志龙 《地震地磁观测与研究》2011,32(2):70-74
介绍一种可同时测量两个正交方向(例如:东西向和南北向)地壳倾斜的双轴单摆体结构的垂直摆倾斜仪的基本原理,并给出其结构设计和初步的实验结果.实验结果表明,地倾斜双轴垂直摆倾斜仪能同时测量两个正交方向的倾斜信号,分辨率达到10-9 rad数量级,能够清晰记录地倾斜固体潮汐信号. 相似文献
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地形变连续观测的资料在国外地学研究中早已受到相当的重视,我国则在近几年才开始受到注意。一些人对水平摆倾斜仪安置在边长只有十几厘米(金属丝水平摆倾斜仪)至多五十几厘米(石英丝水平摆倾斜仪)这样一个很小的三角形底板上,认为它记录到的倾斜量只能是代表一个十分局部的地面运动或是仪器底板本身的倾斜。 相似文献
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0 前言 FSQ型自记水管倾斜仪的观测表明,地倾斜的变化与地震活动的增减有关,在中强地震前往往可以观测到倾斜的前兆异常变化。雅玛里克山1988年11月安装了FSQ型自记水管倾斜仪,并投入了正常的观测记录。两年来的观测实践表明,FSQ型自记水管倾斜仪具有稳定性好、易于标定、便于管理、记录连续、东西、南北两分量固体潮汐清晰、仪器所记录的参数物理意义明确等特点。从而填补了我国东经102°以西(除滇西外)4000000km~2余土地上没有高精度自记水管倾斜仪的空白。 然而在FSQ型自记水管倾斜仪观测中却存在着不容忽视的干扰因素。由于原始观测资料 相似文献
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大同—阳高地震香山,易县台形变前兆分析 总被引：2，自引：0，他引：2
大同—阳高地震前,香山台连通管观测到中短期形变异常。易县台金属摆倾斜仪记录到长达数年的趋势变化,震前一年,速率加快。震前数天,倾斜固体潮汐曲线出现阶变。伸缩仪在震前数小时记录到应变脉冲和短周期扰动,在震后的几次较强余震中,亦有前兆脉冲显示。 作者依据这些震前记录,分析了这两个台各手段形变特征,结合历史资料进行论证。确认可能是大同—阳高地震的前兆信息。文中最后对综合预报过程中的若干问题作了讨论。 相似文献
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新疆柯坪6.5级地震乌什台地倾斜临震异常的对比观测 总被引：1，自引：1，他引：1
1991年2月25日在我台西南方向94km的柯坪县境发生了6.5级地震。震前,我台两套正式观测的倾斜仪和两套临时安装的倾斜仪均观测到了较明显的临震异常。本文仅就其临震异常对比观测资料进行分析和讨论。 相似文献
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通过对地倾斜面上任意一点处的几何学进行较全面的研究,给出了地倾斜面上一点处的方位函数、倾斜不变量以及根据非正交组合的地倾斜观测值计算地面倾斜及其方位角的通用公式,对进行地倾斜观测研究具有一定的实践和理论价值。 相似文献
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Jun Yang 《地震学报(英文版)》1998,11(4):455-465
The relation of tidal factor value to tiltmeter type has been founded from the harmonic analysis for observational data. The
relation is deducted theoretically. It is discovered that the frequency responses of different type tiltmeters and operative
periods or damping constant are slightly different in same station. The tiltmeter of small operative period is able to receive
more precursory information. That is the tidal factors obtained from harmonic analysis for observed data on tiltmeter of different
damping constant are different. The relation between frequency response and tidal factor is searched. It is necessary to calibrate
absolutely tiltmeter to predict earthquake. In order to obtain any amount of ground tilt information, it is necessary to select
appropriately different frequency tiltmeters to make comprehensive observation.
The study is sponsored by the Chinese Joint Seismological Science Foundation, No. 91100. 相似文献
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《Journal of Geodynamics》2010,49(3-5):126-131
It is well known, that high resolution borehole tiltmeters are able to observe deformations, caused by hydrological variations. The quantitative coherence is often unexplained, especially if the sources of deformation can be based on both natural as well as man-made hydrological variations. Since 1999 tilt observations have been taken at the Geodynamic Observatory Moxa in Thuringia/Germany. In two 50 m and one 100 m deep boreholes the ASKANIA tiltmeters are installed. The high quality of the recorded tilt data can be proved by the analysis of well known geodynamic signals like the tides of the solid Earth and the free modes of the Earth. Here we focus on investigations of induced tilt signals caused by pore pressure changes due to precipitation and/or ground water level changes and, in addition, on man-made induced pore pressure variations. The correlation of natural ground water level changes with the observed tilt data can be shown by different events of precipitation and snow melting. However, also the load effect of a big truck yields a small elastic deformation which is clearly detectable in the ground water level recording. The correlated tilt effect is discussed regarding changes of the tilt amplitude and the orientation of the induced pendulum tip movement during the load phase. 相似文献
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倾斜观测载荷干扰源最小"安静"距离理论分析 总被引：5，自引：0，他引：5
作为一种高精度的形变观测,钻孔倾斜观测点必须尽可能避开干扰源。河流、湖泊、仓库(货场、列车编组站)和铁路,是几种主要的影响钻孔倾斜观测的地面载荷变化干扰源。中对这些地面载荷变化干扰影响分别建立了不同的模型,提出了针对一定的干扰限定指标,估计观测点到干扰源的最小“安静”距离的方法。 相似文献
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太原台１９８５年至１９９１年的地应力、地倾斜、连通管和地电阻率４种前兆手段的月均值具有明显的正弦形年变规律，且在年变背景上出现年变幅度的增大或减小。前３种手段还叠加有趋势性上升或下降。用差值法定量地消除年变以后，无震时段变化平稳，有震时段异常突出，较好地反映了大同一阳高地区的中强地震。 相似文献
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F. Bella P. F. Biagi M. Caputo G. Della Monica A. Ermini P. V. Manjgaladze V. Sgrigna D. O. Zilpimiani 《Pure and Applied Geophysics》1995,144(2):277-300
Daily averaged tilt component data from two sites of the Central Apennines (Italy) and of the Southern Caucasus (Georgia), respectively, revealed intermediate-term tilts as possible precursors to earthquakes (M=3.0÷4.7) which occurred in the above-mentioned seismic areas within a distance of 50 km from the sites. A good temporal correlation as well as a fair spatial correspondence between these residual tilts (with amplitude and duration of some microradians and months, respectively) and main shocks were pointed out, by removing both secular trends and seasonal thermoelastic effects from the raw tilts. An attempt was made to justify the above-mentioned results, based on the assumption that the observed intermediate-term preseismic tilts are the manifestation of aseismic creep episodes of comparable duration in the fault materials of thrust faults close to the tilt sites. The mechanism refers to a strain field slowly propagating from the preparation focal area to the tilt site, through crustal blocks separated by weak transition zones. This propagation is thought to be the cause of the local aseismic fault slip recorded by the tiltmeters. Previously, both discrete structures and strain propagation effects were revealed in the Central Apennines and are thought also to exist in the Southern Caucasus. As in the past, the rheological properties of fault materials are revealed as viscoelastic ones. In fact, creep equations obtained by applying several viscoelastic models on our data, proved to fit quite well some of the observed tilt precursors, producing viscosity and rigidity values very similar to those reported in literature.Professor Petr Viktorovich Manjgaladze died during the writing of this paper 相似文献
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During three years preceding the 1976 Friuli earthquake, a continuous southward ground tilt was recorded by a tiltmeter placed near Tolmezzo, 15 km north-west of the epicentre of the impending earthquake. The cumulative ground tilt amounted to as much as 3 minutes of arc. Since the tiltmeter was placed in the proximity of an active fault, such a tilt can be explained if the fault slipped aseismically on its shallower section during the same three year period. Aseismic slip on the fault might have been caused by the same mechanism which concentrated stress in the region and eventually produced the 1976 earthquake. 相似文献
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汶川地震近震源区地形变短期前兆现象的解析 总被引：5，自引：0，他引：5
2008年汶川8.0级地震是我国自建国以来灾难最为严重的一次强地震, 有关震前该区域地壳变形情况引起许多学者的关注。 本文给出了沿龙门山地震带地倾斜及跨龙门山断裂断层水准剖面临震前变化的特征: 汶川地震前沿龙门山地震带分布的康定、 汶川及茂县台地倾斜无明短期显变化; 6个断层水准观测场地, 除耿达场地观测到较大幅度变化有争议外, 其他断层观测场震前均未观测到突出的短临前兆性异常变化。 本文分析了汶川地震前大区域地震活动性资料及震前沿南北地震带显著形变异常点分布特点, 探讨了汶川地震震中区域应变积累过程, 认为近震源区域无显著短期前兆变化现象很可能与震中区域介质所具有的高应变、 小变形性质有关。 另外, 也不排除地形变观测点所处的位置等有关因素。 相似文献