Recent AEM Case Study Examples Using a Full Waveform Time-Domain System for Near-Surface Applications*

Early time or high frequency airborne electromagnetic data (AEM) are desirable for shallow sounding or mapping of resistive areas but this poses difficulties due to a variety of issues, such as system bandwidth, system calibration and parasitic loop capacitance. In an effort to address this issue, a continued system design strategy, aimed at improving its early-channel VTEM data, has achieved fully calibrated, quantitative measurements closer to the transmitter current turn-off, while maintaining reasonably optimal deep penetration characteristics. The new design im plementation, known as “Full Waveform” VTEM was previously described by Legault et al. (2012). This paper presents some case-study examples of the Full Waveform VTEM helicopter time-domain EM system for near-surface applications.