【摘要】 2009年利用大功率人工源极低频电磁技术(CSELF)在位于华北、华南、东北、西北和西南的12个地震台站和几个流动观测点进行了连续30天新的观测试验.结果表明,利用CSELF技术可以在1700 km之外测量到人工源电磁场信号,计算得到的电、磁场功率谱密度和视电阻率与天然源信号相比,抗干扰能力更强,观测信号更稳定,特别有利于识别和捕捉地震等诱发的电磁异常现象,在地震预测监测中具有很大的研究应用潜力.试验还发现,各地震台站和流动测点观测的CSELF信号的强度,与台站或者测量的电、磁场分量相对于发射源的距离、方位有明显的关系;发现在离开发射源的相对近区,场强随距离的衰减,比在相对远区更快;发现接收磁场信号比电场信号较易获得更高信噪比的数据.更多还原

【Abstract】 The new experiment of 30 days was carried out at twelve earthquake monitoring stations and a few mobile observatories located in North, South, NE, NW and SW China using Control Source Extremely Low Frequency (CSELF) electromagnetic technique in 2009.The measurement indicates that the artificial electromagnetic signals can be recorded at stations as far as 1700km from the transmitter.The measured electric and magnetic fields and apparent resistivity using CSELF signals have much more powerful ability to resist the interference of cultural noise in comparison to natural electromagnetic signals.They are much more stable than those using natural signals, which is favorable to identifying the anomalous phenomena caused by earthquake.The experiment shows that CSELF is potentially valuable for earthquake research and prediction.It is also found that the recorded electric and magnetic component amplitude of CSELF signal varies depending on the distance and azimuth of the observatories relative to the transmitter.These amplitudes decline with increasing distance between observatory and transmitter faster within some space extent than those outside the extent.It may be easier for magnetic components to have higher ratio of signal to noise than for electric component.更多还原