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.

中文翻译：

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提高时域电磁测量的效率

地下矿产勘探的长期可持续发展需要有效的深部探测技术和方法。本研究从增强地表-钻孔时域电磁（TEM）技术入手，建立了脉宽（Δ）、目标时间常数（τ）和测量时间（t）之间的新关系。在某些条件下，新公式已扩展到所有使用方波或梯形波形的 TEM 系统。一系列数值模拟说明了地表钻孔、地面和机载 TEM 场的一致行为。新关系使我们能够评估不同关断时间的最佳脉冲宽度并帮助 TEM 测量设计。