Abstract: The Deep Transient Electromagnetic (DTEM) or Long Offset Transient Electromagnetic (LOTEM) is an active electromagnetic measurement method. It is a very efficient exploration method for reaching large penetration depths of up to 10 km.The DTEM is very useful for hydrocarbon exploration in basins covered or inter-bedded by basalt, valcanic layers, salt and anhydrite.In comparison with other electromagnetic method, DTEM has the advantages of being less sensitive to lateral inhomogenities, having the best coupling to the subsoil and measuring in the absence of primary field.This paper provides a briefly summarization of principles and of theory for the DTEM, the technical system in the field, and the data processing and interpretation.

Key words: Transient, Stack, Data-acquisition, Data-processing, Data-interpretation

摘要： 瞬变电磁测深法是一种人工源的电磁方法,适用于寻找火山岩覆盖区以及逆掩推覆体下部的含油气构造、圈定碳酸盐岩地区的低阻和中等电阻的沉积岩系构造。与其它电磁方法比较,有抗干扰能力强、信噪比高、受横向不均匀性的影响小等优点。本文简述了该方法的物理原理、野外测量技术、数据处理及其解释方法。

关键词: 瞬变, 迭加, 数据采集, 处理, 解释