Shallow End Response from ATEM

Abstract:

Different geological, hydrological, environmental and engineering targets are located shallow underground. The information collected with ATEM systems might be very useful for their study; although there are many deeper targets that the ATEM systems are traditionally used for.

The idea to raise magnetic moment output and get deeper penetration response was one of the goals of ATEM systems development during the last decade. The shallow geology response was a trade for such systems, which sometimes were almost blind in the first hundred meter under surface. The possibility to achieve shallow end response from ATEM systems has become significant subject in last years.

Several airborne TDEM systems got second higher frequency and lower magnetic moment signal to pick up shallow response together with deep one. Having a potential advantage such implementation raises complication and cost of the system. There’s no need to receive 500 meter deep response when exploring shallow geology.

P-THEM system having a compact size transmitter and relatively light weight is working on one base frequency at a time, but this frequency can be preset before a flight considering survey goals.

A study of shallow geology response of the P-THEM system working on different base frequency has been conducted in 2014 in Ontario.

The Alliston test area located in Southern Ontario has been flown with the P-THEM system working on base frequencies 30Hz and 90Hz. Results of the observations will be discussed in the presentation.

The shallow end data can be used for mineral exploration applications and also for hydrological and environmental studies.