| - General - |
| Geofile: | NFLD/2063 |
| Companies: | Geological Survey of Canada |
| Contractor: | Geological Survey of Canada |
| Survey Area: | All onshore areas, Newfoundland and Labrador |
| NTS Areas: | All NTS areas |
|
| - Survey Logistics - |
| Survey Date: | 1953 to 1972 for Nfld., early 1967 to 1982 for Labrador (in several phases) |
| Block: | NL Regional |
| Altitude: | 305 m (1000 ft) |
| Line Spacing: | 800 m, Az: 090° (mostly) for Nfld., 090° & 000° for Labrador; Ties: Orthogonal - Az: 000° & 090° |
| Positioning: | fiducials picked on aerial photography, or triangulated from transponders, doppler radar or Loran C for offshore areas; radar altimeter |
| Instrumentation: | (varies with survey phase) |
| Data Recorded: | Levelled, residual mag (originally, vertical component or total field) |
| Comments: | The earliest phase of survey (1953) was flown in the centre of Newfoundland (NTS 12B, 12A & 02D) with a fluxgate magnetometer, yielding vertical component of the magnetic field. For the subsequent phases, magnetic sensors recorded the total magnetic field. Contour maps (1:63 360 scale) of magnetic intensity were generated by first scaling profiles recorded on charts during flights - along straight flight line segments between picked fiducial locations (such as the side of a pond), followed by hand-contouring those values. |
|
| - Digital Data - |
| Grid Cell Size: | 200 m |
| Projection of Data: | NAD27, UTM Zone 21 |
| Data Comments: | During the 1980s, a digital version of the profile data was reconstructed by digitizing and assigning values to the flight line-contour intersections along each flight line, as portrayed on paper aeromagnetic maps. The reconstructed profile data for individual aeromagnetic contour maps were later joined with profiles from adjacent maps to reconstuct airborne survey blocks from each survey phase. In the early 1990s, these data were then levelled to a national standard magnetic grid, together with aeromagnetic data from the Maritime provinces, as part of an East Coast Levelling project (GSC). Similar projects were carried out in other provinces, the result being a seamless, levelled, residual magnetic field for the whole of Canada. The data resolution/precision is limited by the profile data recorded, and the survey methods employed when these surveys were flown, as well as by the smallest contour interval on the aeromagnetic contour maps (5 nT). |
| Links to Data: |
| Mag RMI Export, NAD27, XYZ format (400m grid cell, Nfld., 6.1 Mb zip'd, by gjk) |
| Mag RMI Export, NAD83, XYZ format (400m grid cell, Nfld., 6.2 Mb zip'd, by gjk) |
| Mag and derivative (1VD,AS,TiltD,TiltHD) grids, Geosoft format (400m resolution, Nfld., 15.4 Mb zip'd, by gjk) |
| Mag (RMI & 1VD) grids, NTS 2D & 2E, Geosoft format (100m resolution, Central Nfld., 17.8 Mb zip'd) |
| Mag (RMI & 1VD) grids, NTS 12A & 12H, Geosoft format (100m resolution, Central Nfld., 19.3 Mb zip'd) |
| Mag (RMI & 1VD) grids, NTS 2D,2E,12A & 12H, Geosoft format (100m resolution, Central Nfld., 37.0 Mb zip'd) |
| Mag (RMI & 1VD) grids, NTS 2L,1M & 11P, Geosoft format (100m resolution, South Coast-Burin, Nfld., 14.2 Mb zip'd) |
| Mag (RMI & 1VD) grids, NTS 1L, 1M,11P,2D,2E,12A & 12H, Geosoft format (100m resolution, Central-South Nfld., 51.0 Mb zip'd) |
| Mag (RMI & 1VD) grids, NTS 11O,12B & 12G, Geosoft format (100m resolution, West Coast Nfld., 8.8 Mb zip'd) |
| Mag (RMI & 1VD) grids, NTS 2L,2M,12I & 12P, Geosoft format (100m resolution, Great Northern Peninsula, Nfld., 13.9 Mb zip'd) |
|
| GIS Layers: |
|