时间域大地电磁法及其拟地震解释

TIME DOMAIN MT AND ITS PSEUDO-SEISMIC INTERPRETATION

为提高大地电磁拟地震解释法的应用效果,扩大它的应用范围,本文较详细地论述了时间域大地电磁法的基本原理。提出了一种新的、行之有效的从频率域到时间域大地电磁测深曲线的变换方法。又将作者提出的拟地震解释法运用于时间域大地电磁测深曲线,以求取反射时间序列q_n。与频率域反演相比,取得了良好的效果。这对于大地电磁拟地震解释法的进一步研究具有重要意义。

Among geophysical methods based on the wave theory, some could work in both domains, frequency domain or time domain. Seismic reflection and EM me-thods are taken as an example. However, MT has been only working in frequ-ency domain since it was put forward in the 50s of this century. None of MT experts has paid much attention to the study of the time domain MT although its basic principle was given in a brilliant paper by G. Kunetz in 1972. To enhance the efficiency and expand the applicable domain of the pseudo-seismic interpretation to MT, we begin to study the time domain MT and discuss its basic principle in more detail in this paper. A new approach to transform a frequency domain MT respones into time domain with more effect has been pre-sented. Then by making use of the approach suggested by the author in the paper 'pseudo-seismic interpretation to MT' , we invert the time domain MT curves to compute their corresponding reflectivity time series and get good results as com-pared with that in frequency domain. It will be important for us to study the pseudo-seismic interpretation to MT in the future.