瞬变电磁法小发射回线探测装置及其应用

瞬变电磁法的探测深度主要与观测时间有关。发射回线的尺寸主要是使信号具有一定的强度,以满足接收机灵敏度和信噪比的要求。当对小发射回线装置供以大电流时,同样可以得到和大发射回线相当的信号强度。大发射回线施工中的边缘效应是目前影响探测精度的原因之一,小发射回线装置避免了这个缺陷。云南、湖南和邢台等地的实际探测结果表明,小发射回线装置最大探测深度达800 m,资料解释结果与工程中的揭露、钻孔资料及地质资料一致。

Small transmitter loop device and its application in transient electromagnetic method

In transient electromagnetic exploration,the depth of investigation is related to the observation time.The size of transmitter loop is mainly for strength of signal to satisfy reviver sensitivity and signal to noise ratio.When supplying a small transmitter loop device with power current,the strength of signal as same as that produced by a large transmitter loop can be obtained.At the pre-sent time,detecting precision is subject to the edge effect of large loop configuration and the small loop device avoids this objection.The practice prospecting results in Yunnan,Hunan and Xingtai show that the most deep depth of investigation is up to 800 m by small loop device and the interpretations are agreeable to the facts revealed in engineering,drill data and geological data very well.