EXPLORATION TRENDS & DEVELOPMENTS
AIRBORNE GEOPHYSICAL SURVEYING
n NRG’s Xplorer magnetic and radiometric system in Australia. CREDIT: NRG
E
ON Geosciences reported its busiest year to date, with multiple crews operating for the majority of the year flying several large aeromagnetic, gamma-ray spectrometric, and VLF-EM surveys in Quebec for the Ministry of Energy and Natural Resources (MERN), in Alberta for the Alberta Energy Regulator (AER), in several U.S. states for the United States Geological Survey (USGS), and in Norway for the Geological Survey of Norway (NGU). In 2021 EGL completed numerous helicopter-borne surveys using its MobileMT natural field (25 - 20,000 Hz) EM system, which combines the latest advances in electronics, airborne survey system design, and signal processing techniques to produce high quality data. Over 50,000 line-km of MobileMT data were collected in Australia, North America, South America, and Asia in exploration for gold, porphyry copper, silver, and uranium. Eight MobileMT systems, and two lightweight MobileMTm systems are now available for commercial operations worldwide. The company also offers
8
data processing, data inversion including inverted resistivity-depth models and interpretation services. Worldwide airborne geophysical surveys and consulting services are offered by Aurora, Ont.-based Geotech, and its subsidiaries Geotech Airborne (Johannesburg, SA) and UTS Geophysics (Perth, WA) using its VTEM helicopter time-domain EM and ZTEM natural field EM systems. Also offered are fixed wing and helicopter-borne magnetic, radiometric and gravity surveys. In 2021 surveys included a large (>4,800 line-km) VTEM time domain EM and magnetic survey for the Ontario Geological Survey and the Ministry of Energy, Northern Development and Mines (MENDM) in the Saganash Lake area, near Kapuskasing, Ont. A ZTEM natural field EM survey was also commissioned by the Geological Survey of Sweden (SGU) in northern Sweden. The company continued a multi-year VTEM survey in parts of Rajasthan and Madya states for the Government of India’s Atomic Minerals Directorate (AMD), in the Department
EXPLORATION TRENDS & DEVELOPMENTS | MARCH 2022
of Atomic Energy. Precision GeoSurveys, based in Vancouver, B.C., specializes in low level airborne geophysical surveys in remote and mountainous terrain using a combination of owned and chartered helicopters and fixed wing aircraft. High-resolution magnetic, radiometric, and EM data have been collected for clients in Africa, Asia, Europe, South America, and across North America in a wide variety of geological environments. In 2021, Precision flew EM, magnetic, and radiometric surveys across Canada, in the western U.S., and in Europe. The company also reported it has reduced magnetic noise using new software and hardware as well as improvements to its EM technologies. The following projects were completed by SGL in 2021: another season of combined magnetic, radiometric and SGFEM surveys in Ireland, as part of continuing involvement in the Geological Survey of Ireland’s Tellus project; and in Canada: fixed-wing gravity and magnetic surveys for mineral exploration, fixed-wing radiometric survey for soil mapping,
