Onshore CSEM > In time domain

The need of going from a harmonic transmitter to larger bandwidth straightforward is critical to reach deeper targets. However, it is not an easy task to generate a high-power alternating signal at megahertz frequencies. Instead, the retained solution was to use a time-domain signal, applying a Heaviside signal (simply by measuring fields after direct current is switched off). Then, the deeper we need to estimate the underground; the longer must be the measurement.