等值反磁通瞬变电磁法对水中目标体探测的试验研究

Experimental Study on the Detection of Underwater Targets Using Opposing Coils Transient Electromagnetic Method

等值反磁通瞬变电磁法是针对传统瞬变电磁法存在浅层探测盲区这一缺点而提出来的一种新方法,该方法对浅层低阻体的探测具有明显优势。介绍了等值反磁通瞬变电磁方法原理、此次实验所用仪器设备以及浅水域等值反磁通瞬变电磁法的探测过程,通过在渤海海域中对水中目标体进行电磁探测方法试验,分析了不同埋深、不同材质和不同采集参数的电磁异常响应特征,结果表明:采用等值反磁通瞬变电磁法能够克服一次场干扰,从而精细识别水中浅层目标体。试验结果显示:采用小线圈探测能够识别水中5 m内较薄的金属目标体,探测其他较大目标体可根据缩比公式进行推算。该试验可为水中目标体电磁探测提供相应的采集参数等基础参考资料。

The opposing coils transient electromagnetic method is a new method proposed to address the drawback of shallow detection blind spots in traditional transient electromagnetic methods.This method has obvious advantages in detecting shallow low resistance bodies.This article introduces the principle of the opposing coils transient electromagnetic method,the instruments and equipment used in this experiment,and the detection process of shallow water opposing coils transient electromagnetic method.Through electromagnetic detection method experiments on underwater targets in the Bohai Sea area,the electromagnetic anomaly response characteristics of different burial depths,different materials,and different collection parameters were analyzed.The results showed that using the opposing coils transient electromagnetic method can overcome primary field interference,to accurately identify shallow targets in water.The experiment showed that using small coil detection can identify thinner metal targets within 5 m in water,and other larger targets detection can be calculated based on the scaling formula.This experiment provided basic reference materials such as corresponding collection parameters for the electromagnetic detection of underwater targets.