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Airborne electromagnetic/magnetic survey data were acquired for the area between April 17 and April 30, 2015. The aircraft flight elevation was maintained at a nominal ground clearance of 83 m. Aircraft navigation used a 12-channel NovaTel dual frequency GPS. A vertically mounted video camera was used to record images of the ground. The radar height was recorded ten times per second using a Sperry unit and the barometric altitude was recorded ten times per second using a Motorola altitude transducer. The magnetic data were recorded 10 times per second using a Scintrex CS-2 cesium-vapor magnetometer.

This high sensitivity aeromagnetic survey was carried out by Goldak Airborne Surveys (Goldak) on behalf of the Geological Survey of Canada (GSC) between January 25th and March 26th, 2011. Aircraft equipment operated included three cesium vapour magnetometers, a GPS real-time and post-corrected differential positioning system, a flight path recovery camera, VHS titling and recording system, as well as radar and barometric altimeters. All data were recorded digitally in GEDAS binary file format. Reference ground equipment included two GEM Systems GSM-19W Overhauser magnetometers and a Novatel 12 channel GPS base station which was set up at the base of operations for differential post-flight corrections. Eighty two flights (including test and calibration sorties) were required to complete the survey block. A total of 37,999 line kilometres of high resolution magnetic data were collected, processed and plotted. The traverse lines were flown at a spacing of 400 m with control lines flown at a separation of 2400 m. Nominal terrain clearance was specified at 100 m above ground.

Reprocessing of magnetic data for Yukon was performed between November 2016 and March 2017. Aeromagnetic data were compiled, data of different resolutions were merged, and a series of images individually levelled for each map sheet were produced. For each 250k-scale map, the following magnetic derivative maps were produced: 1. Residual Total Magnetic Field; 2. Reduced-to-Pole Magnetic Field (RTP); 3. First Vertical Derivative of the Reduced-to-Pole Magnetic Field (RTP_VD); and 4. Tilt Derivative of the Reduced-to-Pole Magnetic Field (RTP_TDR). These maps are provided as pdfs, geotiffs and Geosoft grid files. Colour ramps/legends are provided for each map.

Reprocessing of magnetic data for Yukon was performed between November 2016 and March 2017. Aeromagnetic data were compiled, data of different resolutions were merged, and a series of images individually levelled for each map sheet were produced. For each 250k-scale map, the following magnetic derivative maps were produced: 1. Residual Total Magnetic Field; 2. Reduced-to-Pole Magnetic Field (RTP); 3. First Vertical Derivative of the Reduced-to-Pole Magnetic Field (RTP_VD); and 4. Tilt Derivative of the Reduced-to-Pole Magnetic Field (RTP_TDR). These maps are provided as pdfs, geotiffs and Geosoft grid files. Colour ramps/legends are provided for each map.

This map of the residual total magnetic field was derived from data acquired during a helicopter-borne aeromagnetic survey carried out by Fugro Airborne Surveys during the period between February 4 to March 15, 2010. The data were recorded using split-beam cesium vapour magnetometers (sensitivity = 0.005 nT) rigidly mounted on each of the two Astar 350B aircraft (C-FGSC and C-GAVO). The nominal traverse and control line spacings were, respectively, 400 m and 2 400 m, and the aircraft flew at a nominal terrain clearance of 100 m. Traverse lines were oriented N30°E with orthogonal control lines. The flight path was recovered following post-flight differential corrections to the raw Global Positioning System data and inspection of ground images recorded by a vertically-mounted video camera. The survey was flown on a pre-determined flight surface to minimize differences in magnetic values at the intersections of control and traverse lines

This map of the first vertical derivative of the magnetic field was derived from data acquired during an aeromagnetic survey carried out by Goldak Airborne Surveys during the period of May 16 to July 1, 2009. The data were recorded using a split-beam cesium vapour magnetometer mounted in the tail boom of a Piper Navajo aircraft. The nominal traverse and control line spacings were 400 m and 2400 m, respectively, and the aircraft flew at a nominal terrain clearance of 150 m.

This map of the first vertical derivative of the magnetic field was derived from data acquired during an aeromagnetic survey carried out by EON Geosciences Inc. during the period between April 12, 2010 to June 2, 2010. The data were recorded using a split-beam cesium vapour magnetometer (sensitivity = 0.005 nT) mounted in the tail boom of a Piper Navajo aircraft. The nominal traverse and control line spacings were, respectively, 800 m and 2 400 m, and the aircraft flew at a nominal terrain clearance of 250 m. Traverse lines were oriented N45°E with orthogonal control lines. The flight path was recovered following post-flight differential corrections to the raw Global Positioning System data and inspection of ground images recorded by a vertically-mounted video camera. The survey was flown on a pre-determined flight surface to minimize differences in magnetic values at the intersections of control and traverse lines. These differences were computer-analysed to obtain a mutually levelled set of flight-line magnetic data. The levelled values were then interpolated to a 200 m grid. The International Geomagnetic Reference Field (IGRF) was not removed from the magnetic field.

This map of the first vertical derivative of the magnetic field was derived from data acquired during an aeromagnetic survey carried out by Goldak Airborne Surveys during the period of May 16 to July 1, 2009. The data were recorded using a split-beam cesium vapour magnetometer mounted in the tail boom of a Piper Navajo aircraft. The nominal traverse and control line spacings were 400 m and 2400 m, respectively, and the aircraft flew at a nominal terrain clearance of 150 m.

This aeromagnetic survey was carried out by Novatem Inc. from February 23, 2019 to April 2, 2019. The data were recorded using split-beam cesium vapour magnetometers mounted in the tail booms of two Piper Navajo aircraft. The nominal traverse and control line spacings were 400 m and 2400 m, and the aircraft flew at a nominal terrain clearance of 150 m. Traverse lines were oriented N45°E with orthogonal control lines.