关键词: 震电效应, 双电层模型, 孔隙介质, 频域有限差分方法, 数值模拟

Abstract:

The seismoelectric effect is an important representation of the seismoelectric transformation phenomenon in underground porous media. It can be used to detect underground oil, gas, and other pore fluids. In the numerical simulation of seismoelectric effect, traditionally the quasi-static approximation is adopted for the theoretical simulation of electromagnetic response. However, the quasi-static approximation ignores the influence of seismic shear waves, leading to significant errors in the simulation of electromagnetic field, and may not satisfy the premise of applying quasi-static in some cases. In order to accurately reveal the mechanism of seismoelectric effect, a finite difference method in frequency domain based on Maxwell’s full equation is proposed to simulate the frequency electromagnetic response of seismoelectric  effects, and the seismoelectric characteristics of the layered and anomalous conductivity models in an elastic homogeneous medium are analyzed and discussed. The results show that the reflection and transmission of electromagnetic wave field can be characterized by the Maxwell’s full equation numerical simulation more accurately at the interface of different media, and the abnormal position can be more accurately identified. This provides a new idea for improving the resolution of deep underground oil and gas detection.

Key words: seismoelectric effect')">

seismoelectric effect, electric double layer, porous media, frequency domain , finite difference method, numerical simulation