QUE27-98.gsb
Also found with file name NA27SCRS.GSB. Uses NT method which expects longitudes positive west; EPSG GeogCRSs NAD27 (code 4267) and NAD83(CSRS) (code 4617) have longitudes positive east. Can be taken as an approximate CT NAD27 to WGS 84 - see code 1692.
Geodetic Service of Quebec. Contact alain.bernard@mrn.gouv.qc.ca
2023-07-17
Engineering survey, topographic mapping.
United States (USA) - Alaska - east of 141°W; i.e. Panhandle.
Cartesian 2D CS. Axes: easting, northing (X,Y). Orientations: east, north. UoM: ftUS.
15589276.78 7208303.31
11085650.95 2295583.22
21023056.94 11475883.28
-79.85 44.99
-57.1 62.62
Definition: OGC Well Known Text 2 (2019)
BOUNDCRS[ SOURCECRS[ PROJCRS["NAD27 / Alaska zone 1", BASEGEOGCRS["NAD27", DATUM["North American Datum 1927", ELLIPSOID["Clarke 1866",6378206.4,294.978698213898, LENGTHUNIT["metre",1]]], PRIMEM["Greenwich",0, ANGLEUNIT["degree",0.0174532925199433]], ID["EPSG",4267]], CONVERSION["Alaska CS27 zone 1", METHOD["Hotine Oblique Mercator (variant A)", ID["EPSG",9812]], PARAMETER["Latitude of projection centre",57, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8811]], PARAMETER["Longitude of projection centre",-133.666666666667, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8812]], PARAMETER["Azimuth of initial line",323.130102361111, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8813]], PARAMETER["Angle from Rectified to Skew Grid",323.130102361111, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8814]], PARAMETER["Scale factor on initial line",0.9999, SCALEUNIT["unity",1], ID["EPSG",8815]], PARAMETER["False easting",16404166.67, LENGTHUNIT["US survey foot",0.304800609601219], ID["EPSG",8806]], PARAMETER["False northing",-16404166.67, LENGTHUNIT["US survey foot",0.304800609601219], ID["EPSG",8807]]], CS[Cartesian,2], AXIS["easting (X)",east, ORDER[1], LENGTHUNIT["US survey foot",0.304800609601219]], AXIS["northing (Y)",north, ORDER[2], LENGTHUNIT["US survey foot",0.304800609601219]], USAGE[ SCOPE["Engineering survey, topographic mapping."], AREA["United States (USA) - Alaska - east of 141°W; i.e. Panhandle."], BBOX[54.61,-141,60.35,-129.99]], ID["EPSG",26731]]], TARGETCRS[ GEOGCRS["NAD83(CSRS)v2", DATUM["North American Datum of 1983 (CSRS) version 2", ELLIPSOID["GRS 1980",6378137,298.257222101, LENGTHUNIT["metre",1]]], PRIMEM["Greenwich",0, ANGLEUNIT["degree",0.0174532925199433]], CS[ellipsoidal,2], AXIS["geodetic latitude (Lat)",north, ORDER[1], ANGLEUNIT["degree",0.0174532925199433]], AXIS["geodetic longitude (Lon)",east, ORDER[2], ANGLEUNIT["degree",0.0174532925199433]], USAGE[ SCOPE["Horizontal component of 3D system."], AREA["Canada - onshore and offshore - Alberta; British Columbia; Manitoba; New Brunswick; Newfoundland and Labrador; Northwest Territories; Nova Scotia; Nunavut; Ontario; Prince Edward Island; Quebec; Saskatchewan; Yukon."], BBOX[38.21,-141.01,86.46,-40.73]], ID["EPSG",8237]]], ABRIDGEDTRANSFORMATION["NAD27 to NAD83(CSRS)v2 (1)", METHOD["NTv2", ID["EPSG",9615]], PARAMETERFILE["Latitude and longitude difference file","QUE27-98.gsb"], USAGE[ SCOPE["Transformation of coordinates at 1m to 2m level of accuracy."], AREA["Canada - Quebec."], BBOX[44.99,-79.85,62.62,-57.1]], ID["EPSG",9239], REMARK["Also found with file name NA27SCRS.GSB. Uses NT method which expects longitudes positive west; EPSG GeogCRSs NAD27 (code 4267) and NAD83(CSRS) (code 4617) have longitudes positive east. Can be taken as an approximate CT NAD27 to WGS 84 - see code 1692."]]]
Definition: JSON
{ "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json", "type": "BoundCRS", "source_crs": { "type": "ProjectedCRS", "name": "NAD27 / Alaska zone 1", "base_crs": { "name": "NAD27", "datum": { "type": "GeodeticReferenceFrame", "name": "North American Datum 1927", "ellipsoid": { "name": "Clarke 1866", "semi_major_axis": 6378206.4, "semi_minor_axis": 6356583.8 } }, "coordinate_system": { "subtype": "ellipsoidal", "axis": [ { "name": "Geodetic latitude", "abbreviation": "Lat", "direction": "north", "unit": "degree" }, { "name": "Geodetic longitude", "abbreviation": "Lon", "direction": "east", "unit": "degree" } ] }, "id": { "authority": "EPSG", "code": 4267 } }, "conversion": { "name": "Alaska CS27 zone 1", "method": { "name": "Hotine Oblique Mercator (variant A)", "id": { "authority": "EPSG", "code": 9812 } }, "parameters": [ { "name": "Latitude of projection centre", "value": 57, "unit": "degree", "id": { "authority": "EPSG", "code": 8811 } }, { "name": "Longitude of projection centre", "value": -133.666666666667, "unit": "degree", "id": { "authority": "EPSG", "code": 8812 } }, { "name": "Azimuth of initial line", "value": 323.130102361111, "unit": "degree", "id": { "authority": "EPSG", "code": 8813 } }, { "name": "Angle from Rectified to Skew Grid", "value": 323.130102361111, "unit": "degree", "id": { "authority": "EPSG", "code": 8814 } }, { "name": "Scale factor on initial line", "value": 0.9999, "unit": "unity", "id": { "authority": "EPSG", "code": 8815 } }, { "name": "False easting", "value": 16404166.67, "unit": { "type": "LinearUnit", "name": "US survey foot", "conversion_factor": 0.304800609601219 }, "id": { "authority": "EPSG", "code": 8806 } }, { "name": "False northing", "value": -16404166.67, "unit": { "type": "LinearUnit", "name": "US survey foot", "conversion_factor": 0.304800609601219 }, "id": { "authority": "EPSG", "code": 8807 } } ] }, "coordinate_system": { "subtype": "Cartesian", "axis": [ { "name": "Easting", "abbreviation": "X", "direction": "east", "unit": { "type": "LinearUnit", "name": "US survey foot", "conversion_factor": 0.304800609601219 } }, { "name": "Northing", "abbreviation": "Y", "direction": "north", "unit": { "type": "LinearUnit", "name": "US survey foot", "conversion_factor": 0.304800609601219 } } ] }, "id": { "authority": "EPSG", "code": 26731 } }, "target_crs": { "type": "GeographicCRS", "name": "NAD83(CSRS)v2", "datum": { "type": "GeodeticReferenceFrame", "name": "North American Datum of 1983 (CSRS) version 2", "ellipsoid": { "name": "GRS 1980", "semi_major_axis": 6378137, "inverse_flattening": 298.257222101 } }, "coordinate_system": { "subtype": "ellipsoidal", "axis": [ { "name": "Geodetic latitude", "abbreviation": "Lat", "direction": "north", "unit": "degree" }, { "name": "Geodetic longitude", "abbreviation": "Lon", "direction": "east", "unit": "degree" } ] }, "id": { "authority": "EPSG", "code": 8237 } }, "transformation": { "name": "NAD27 to NAD83(CSRS)v2 (1)", "method": { "name": "NTv2", "id": { "authority": "EPSG", "code": 9615 } }, "parameters": [ { "name": "Latitude and longitude difference file", "value": "QUE27-98.gsb", "id": { "authority": "EPSG", "code": 8656 } } ], "id": { "authority": "EPSG", "code": 9239 } } }
Definition: Mapnik
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