Northwest Territories Geological Survey Geophysical Activities, 2019-2020Theatre Lobby
The Northwest Territories Geological Survey (NTGS) holds a large collection of government and industry geophysical data and has the mandate to make these data available to the public. The NTGS’s online data access systems have been upgraded to simplify client access to this collection. Three new publications are presented and will be available in the near future such as, an updated compilation of airborne geophysical data, geophysical interpretation of Banks Island and a new aeromagnetic survey in the Slave Geological Province.
To aid users in finding available geophysical data, all publically available airborne magnetic, electromagnetic, radiometric, and gravity data conducted in the NWT by federal and territorial governments and industry are represented here on three compilation maps. These finding aids will be published shortly as NTGS Open Report 2019-018.
The Banks Island aeromagnetic data submitted and donated by industry was checked for errors, and enhanced by new interpretive grids. Two compilation maps were produced from the interpretation of all calculated geophysical products of Green River and Parker River areas. The geophysical interpretation is based on a multi-dataset stacking technique in which the expression of features is compared across various data layers, and features are manually traced. The reduced-to-pole residual magnetic field, first vertical derivative, second vertical derivative, tilt derivative, and analytic signal grids were used during the interpretation process, as input for calculations and as data layers.The goal of this geophysical interpretation of aeromagnetic data is to delineate structures that are potentially prospective for mineralization and identify targets for future work. Several linear or curvilinear features in this aeromagnetic dataset have been interpreted as dykes, faults, and lineaments. One hundred and twenty-six of the best potential kimberlite targets were selected in the Parker River area and seventy-eight in the Green River area. The geophysical interpretation of the Banks Island dataset will be published as NTGS Open File 2019-03.
During the winter of 2019, from February 13th to May 25th, an airborne high-resolution magnetic survey in the Itchen Lake and Point Lake areas was flown for the Northwest Territories Geological Survey by EON Geoscience Inc. The survey area is located in the Slave craton of the Northwest Territories, covering NTS 086H, 086A, and 076E. The nominal traverse line spacing was 100 m with east-west direction and control lines spacing 600 m with north-south direction. The nominal aircraft terrain clearance was 60 m with drape flying. Previous to this study, only low-resolution regional aeromagnetic data was publically available. This new high-resolution aeromagnetic data can be used by multiple stakeholders to enhance geoscience knowledge, promote mineral exploration, and inform land-use planning decisions. The aeromagnetic data of Itchen Lake and Point Lake is published as NTGS Open Report 2019-003.