The long-term sustainable development of mineral exploration under covers require effective deep detection techniques and methods. Start from enhancing the surface-borehole time-domain electromagnetic (TEM) technique, the present study established a new relationship between the pulse width (Δ), the target time constant (τ) and the measurement time (t). Under certain conditions, the new formula has been extended to all TEM systems that use square or trapezoidal waveforms. A series of numerical simulations illustrate the consistent behaviors of the surface-borehole, ground and airborne TEM fields. The new relationship allows us to evaluate optimal pulse widths for different off-times and to help TEM survey design.
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This work was funded by the Fond de Recherche du Québec-Nature et technologies (FRQNT) with industry partner Abitibi Geophysique and Agnico Eagle Mines Limited. We sincerely thank the reviewers for their valuable comments that help to improve the present paper.
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Liu, C., Cheng, L., Dai, X. et al. Improvement of the Efficiency of Time-Domain Electromagnetic Measurement. Pure Appl. Geophys. (2020) doi:10.1007/s00024-020-02419-x
- Time-domain electromagnetic
- time constant
- pulse width
- signal quality