Research study on the short offset time-domain electromagnetic method for deep exploration

As a kind of geophysical method, the principle of transient electromagnetic method (TEM) observes the secondary vortex field in the gap of the primary field, which is applied to the investigation of resources and environmental engineering survey. In order to realize the rapid and precise detection of the deep targets (due to its relative great detection depth and high accuracy), the short offset time-domain electromagnetic method (SOTEM) is proposed in this paper. In addition, its feasibility, observation and interpretation techniques are researched. The results show that SOTEM has the same near source detection capability as the central loop configuration when choosing the step waveform, and as a result, the primary and secondary fields can be separated theoretically. The application has shown the effectiveness and superiority of SOTEM in the deep target exploration.