Helitem

CGG’s Helitem^® is a broad-spectrum helicopter electromagnetic system capable of collecting data at base frequencies as low as 7.5 Hz. This means Helitem can now image the Earth’s resistivity to greater depths than other systems, while retaining resolving power throughout the section due to its innovative transmitter waveform.

Historically, receiver motion-induced noise has been the primary limiting factor in acquiring useful low base frequency airborne electromagnetic data. Evolutions in the design of CGG’s Helitem system in terms of both receiver electronics and a patented receiver suspension system now allow operation at a base frequency of 7.5 Hz. An innovative change in transmitter pulse-shape also enables early off-time measurement and effective energizing of deep conductive targets.

CGG’s powerful Helitem system offers the lowest transmitter base frequency
of 7.5 Hz, unparalleled depth of penetration, and resolving power
throughout the section"

The advantage of data collection from the air is the ease of access to remote sites where ground data collection is challenging, and the ability to collect data quickly and efficiently over your entire license area. The Helitem time domain electromagnetic system provides important geological information for exploration projects where the target zones are conductive.

In a comparison of 30 Hz Helitem resistivity data and 7.5 Hz Helitem resistivity data at 500m below ground, the lower base frequency shows a marked improvement in deep target identification. The circles indicate known targets at 200m (right) and 400m (left) depth. The 30 Hz data does not image the deeper target while the 7.5 Hz data does.