Electrode Optimization for Electric Field Detection in Magnetotelluric Regional Monitoring

Abstract

Monitoring deep subgrade structures in complex geological environments is challenging. To address this problem, this paper proposes an electrode optimization method for electric field detection in regional magnetotelluric monitoring. First, a dynamic electrode selection model is established. The KD-tree algorithm is used to optimize measurement point distribution. Combined with non-orthogonal electric field calculation, an analytical relationship between the subgrade strike angle and the projection matrix is derived. Then, tilt angle compensation correction is performed. This method overcomes the limitation of irregular strike directions. It achieves full monitoring coverage of the subgrade and its two sides. It provides core technical support for early warning of subgrade defects.