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通过实验论证平凉地震台深井电阻率观测自然电位畸变由电极交叉供电造成,讨论分析不同电极供电对自然电位的影响。结果表明:对测量极供电,会影响自然电位,不会影响电阻率测值;单极供电对自然电位的影响表现为阶跃突跳,并以指数形态恢复,恢复时间约10 h,干扰峰值与供电电流、供电时间等有关;对观测数据进行校正,取得较好效果。 相似文献
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Discussion on several important problems in earthquake-related electromagnetic disturbance monitoring in China
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Earthquake-related electromagnetic observation aims at finding abnormal electromagnetic variation associated with earthquake possibly. The existing studies have proved that this method is, to a large extent, effective in short-term and impending earthquake predication. This paper summarizes progress and discusses some related problems in this field. Some requirements for observation system have been proposed to improve monitoring level. As a case observation using the reformed observation system in Jinghai seismologic station, Tianjin, some results are given. 相似文献
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2001年8~9月间,江油地电台N10°E测向视电阻率ρs值出现持续下降,变化形态打破年变,降幅约3%,很像是一次孕震异常。但经现场核实为供电电源极性接反漏电所致,与理论计算出的漏电影响系数相反。 相似文献
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Geophysics For Slope Stability 总被引:2,自引:0,他引:2
Robert Hack 《Surveys in Geophysics》2000,21(4):423-448
A pre-requisite in slope stability analyses is that the internal structure and the mechanical properties of the soil or rock mass of the slope, are known or can be estimated with a reasonable degree of certainty. Geophysical methods to determine the internal structure of a soil or rock mass may be used for this purpose. Various geophysical methods and their merits for slope stability analyses are discussed. Seismic methods are often the most suitable because the measurements depend on the mechanical properties that are also important in the mechanical calculation of slope stability analyses. Other geophysical methods, such as electromagnetic, electric resistivity, self-potential, and gravity methods, may be useful to determine the internal structure, but require a correlation of found boundaries with mechanical properties. 相似文献
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地震发生前的电磁异常现象已被地面、卫星等多种观测手段观测到.目前,我国已经建成了100多个水平地电场观测台站,然而对于垂直电场的观测仍是一个空白.自2009年4月开始,在甘肃天祝地震前兆科学台阵的红沙湾、黄羊川、松山建立了3个垂直电场观测试验站,进行垂直地电场的试验观测,在我国专门的垂直地电场观测试验研究尚属首次.通过近1年的观测试验,取得了有价值的观测资料.从数据的初步结果来看,垂直电场的日变化形态清晰,黄羊川和松山观测数据的日变幅度在16 mV/km左右,红沙湾观测数据的日变幅度在8 mV/km左右;垂直电场日变化周期的主要成分是24小时的全日波,其次是12小时周期的半日波. 相似文献