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在单轴压力下对辉长岩、大理岩等岩石破裂过程中产生的电、磁、声信号作了实验研究．实验分干、湿两种情况进行，测试系统的频响范围为超低频．主要结果是：获得了岩样从受压到解体过程中，在０—２０ｋＨｚ频段内的电磁辐射和声发射信号的原始波形；岩石破裂过程中电磁信号的辐射强度与岩石的岩性、含水量、破裂强度、加载率和破裂状态有关；岩石破裂过程中的电磁辐射率和声发射率有关系，它们的最大值在时间上相对应的约占７０％，而且电磁辐射信号比声发射信号发育，持续时间也较长；实验中以铜板天线为接收传感器的电磁信号的主能潜在６ｋＨｚ以下，而以电感线圈为接收传感器的电磁信号主能谱在１０ｋＨｚ左右，声发射的主能谱在３ｋＨｚ以下；声发射信号出现之前有明显的电磁信号．由于岩石在破裂过程中辐射的电磁信号与声发射有较好的对应关系，因此可以认为，岩石破裂实验中获得的电磁辐射信号与岩石破裂有密切的关系．所以，地震前观测到的电磁辐射异常主要是由岩石的破裂引起的．至于实验中在声发射之前出现的电磁信号，则可能与压电、压磁效应有关．
Under uniaxial pressure, the electrical, magnetic and acoustic signals generated during the rock burst of gabbro and marble are experimentally studied. Experimental points dry, wet two cases, the test system frequency range of ultra-low frequency. The main results are as follows: The original waveform of electromagnetic radiation and acoustic emission signal in the frequency band from 0 to 20 kHz is obtained during the process of rock compression from disintegration; the radiation intensity of the electromagnetic signal during the rock burst is related to the lithology and water content of the rock , The rupture strength, the loading rate and the rupture state. The relationship between the electromagnetic radiation rate and the acoustic emissivity in the process of rock rupture has a maximum of about 70% of the time, and the electromagnetic radiation signal is more specific than the acoustic emission signal , The duration is also longer; in the experiment, the main energy of the electromagnetic signal received by the copper antenna is below 6 kHz, while the main energy spectrum of the electromagnetic signal received by the inductor is about 10 kHz. The main energy spectrum of the acoustic emission is at 3 kHz The following; acoustic emission signal before there is a clear electromagnetic signal. Because the rock has a good correspondence between electromagnetic radiation and acoustic emission in the process of rupture, it can be considered that the electromagnetic radiation signal obtained in the rock rupture experiment is closely related to rock rupture. Therefore, the abnormal electromagnetic radiation observed before the earthquake was mainly caused by the rupture of the rock. As for the electromagnetic signal that appears before the acoustic emission in the experiment, it may be related to the piezoelectric and piezomagnetic effect.