Study on the detection technology and response of isolated anomalous bodies in transient electromagnetic wave logging of formations

Abstract

Transient electromagnetic wave logging is one of the key methods for detecting underground formations, especially for identifying anomalies near wells using higher frequencies and resolutions. In this paper, the 3D TDFD (three-dimensional time-domain finite-difference) simulation method is used to investigate the detection technique of wellbore anomalies based on the scattered field of transient electromagnetic waves and its significance in underground structure identification and localization. The research results show that isolated anomalies can be effectively characterized by extracting the scattering field response generated by block-shaped anomalies while eliminating the contribution of background media. Analyzing the measurement response caused by scatterers provides important information about the position, size, and response magnitude of the anomalies, offering an effective method for detecting and identifying wellbore anomalies. Applying this detection technique enriches the existing methods for wellbore anomaly detection, providing important theoretical and technical foundations for petroleum and solid mineral exploration, as well as the construction of underground defense engineering.