低频交流电法的试验和研究

EXPERIMENT AND DISCUSSION ON THE LOWFREQUENCY A.C. METHOD

摘要:

本文介绍了关于低频交流电法的试验和研究结果:
(1)现场观测证实,低频交流电法与直流电法观测的电阻率数据(包括ρ,曲线变化)是同步的和相近的。
(2)交流电法的抗干扰(噪声)能力比直流电法有所增强。采用交流电法守将干扰(噪声)背景由通常的100μv压低到10μv,並可以完全消除风扰。
(3)采用交流电法可以提高观测精度,其观测精度为10^-3(直流电法精度为10^-2,还可有效地分辨1-2%的地电前兆异常。
(4)探测同样深度,交流电法可比直流电法功耗减少一倍。

Abstract:

A. C. Method began to be applied in the geoelectrical observations by using a set of equipments of type Mark-4 with accuracy of 10^-3 in 1976, The results of experimental observations in terms of A. C. Method are presented in this paper as the following:
(1) The results from A. C. and D. C. method are agreeable.
(2) Signal-to-noise ratio can be increased in one digit number.
(3) The accuracy of A. C. method is 10^-3 but D. C. method is 10^-2. The resistivity anomalous of precursor phenomena up to 1-2% may be determined.
(4) For same depth, power consumption may be decreased by A. C. method.