Airborne electromagnetic surveys have a strong Canadian history due to the highly resistive and easily penetrated Canadian basement to electromagnetic fields. In tropical areas, the ground is generally more electrically conductive. In all cases, the time-domain method is the most efficient electromagnetic method because it is less sensitive to the near surface conductivity contrasts.
In mineral exploration, the need is mainly for deep penetration while in the environmental investigation, the need is to map at shallow depths with a highly resolution.
NOVATEM is a heliborne Time-domain electromagnetic system with a central loop configuration designed by NOVATEM to provide both a great penetration for TDEM prospecting and a high resolution for TDEM sounding.