May76v20.gsb
Uses NT method which expects longitudes positive west; EPSG GeogCRSs NAD27(76) (code 4608) and NAD83 (code 4269) have longitudes positive east. May be taken as approximate transformation NAD27(76) to WGS 84 - see code 1690.
Geodetic Survey of Canada http://www.geod.nrcan.gc.ca/
2019-09-17
metre
North American Datum 1927 (1976)
EPSG
Surveys and Mapping Section; Ontario Ministry of Transportation.
2000-03-07
31654.23 5467337.64
-766930.83 5327791.05
-554348.09 6397581.35
-95.16 41.67
-74.35 56.9
Definition: OGC Well Known Text 2 (2019)
BOUNDCRS[ SOURCECRS[ PROJCRS["NAD27(76) / MTM zone 12", BASEGEOGCRS["NAD27(76)", DATUM["North American Datum 1927 (1976)", ELLIPSOID["Clarke 1866",6378206.4,294.978698213898, LENGTHUNIT["metre",1]]], PRIMEM["Greenwich",0, ANGLEUNIT["degree",0.0174532925199433]], ID["EPSG",4608]], CONVERSION["MTM zone 12", METHOD["Transverse Mercator", ID["EPSG",9807]], PARAMETER["Latitude of natural origin",0, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8801]], PARAMETER["Longitude of natural origin",-81, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8802]], PARAMETER["Scale factor at natural origin",0.9999, SCALEUNIT["unity",1], ID["EPSG",8805]], PARAMETER["False easting",304800, LENGTHUNIT["metre",1], ID["EPSG",8806]], PARAMETER["False northing",0, LENGTHUNIT["metre",1], ID["EPSG",8807]]], CS[Cartesian,2], AXIS["(E)",east, ORDER[1], LENGTHUNIT["metre",1]], AXIS["(N)",north, ORDER[2], LENGTHUNIT["metre",1]], USAGE[ SCOPE["Engineering survey, topographic mapping."], AREA["Canada - Ontario - between 82°30'W and 79°30'W: north of 46°N in area between 82°30'W and 80°15'W, north of 47°N in area between 80°15'W and 79°30'W."], BBOX[46,-82.5,55.21,-79.5]], ID["EPSG",2021]]], TARGETCRS[ GEOGCRS["NAD83", DATUM["North American Datum 1983", 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["Geodesy."], AREA["North America - onshore and offshore: Canada - Alberta; British Columbia; Manitoba; New Brunswick; Newfoundland and Labrador; Northwest Territories; Nova Scotia; Nunavut; Ontario; Prince Edward Island; Quebec; Saskatchewan; Yukon. Puerto Rico. United States (USA) - Alabama; Alaska; Arizona; Arkansas; California; Colorado; Connecticut; Delaware; Florida; Georgia; Hawaii; Idaho; Illinois; Indiana; Iowa; Kansas; Kentucky; Louisiana; Maine; Maryland; Massachusetts; Michigan; Minnesota; Mississippi; Missouri; Montana; Nebraska; Nevada; New Hampshire; New Jersey; New Mexico; New York; North Carolina; North Dakota; Ohio; Oklahoma; Oregon; Pennsylvania; Rhode Island; South Carolina; South Dakota; Tennessee; Texas; Utah; Vermont; Virginia; Washington; West Virginia; Wisconsin; Wyoming. US Virgin Islands. British Virgin Islands."], BBOX[14.92,167.65,86.45,-40.73]], ID["EPSG",4269]]], ABRIDGEDTRANSFORMATION["NAD27(76) to NAD83 (1)", METHOD["NTv2", ID["EPSG",9615]], PARAMETERFILE["Latitude and longitude difference file","May76v20.gsb"], USAGE[ SCOPE["Not known."], AREA["Canada - Ontario."], BBOX[41.67,-95.16,56.9,-74.35]], ID["EPSG",1463], REMARK["Uses NT method which expects longitudes positive west; EPSG GeogCRSs NAD27(76) (code 4608) and NAD83 (code 4269) have longitudes positive east. May be taken as approximate transformation NAD27(76) to WGS 84 - see code 1690."]]]
Definition: JSON
{ "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json", "type": "BoundCRS", "source_crs": { "type": "ProjectedCRS", "name": "NAD27(76) / MTM zone 12", "base_crs": { "name": "NAD27(76)", "datum": { "type": "GeodeticReferenceFrame", "name": "North American Datum 1927 (1976)", "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": 4608 } }, "conversion": { "name": "MTM zone 12", "method": { "name": "Transverse Mercator", "id": { "authority": "EPSG", "code": 9807 } }, "parameters": [ { "name": "Latitude of natural origin", "value": 0, "unit": "degree", "id": { "authority": "EPSG", "code": 8801 } }, { "name": "Longitude of natural origin", "value": -81, "unit": "degree", "id": { "authority": "EPSG", "code": 8802 } }, { "name": "Scale factor at natural origin", "value": 0.9999, "unit": "unity", "id": { "authority": "EPSG", "code": 8805 } }, { "name": "False easting", "value": 304800, "unit": "metre", "id": { "authority": "EPSG", "code": 8806 } }, { "name": "False northing", "value": 0, "unit": "metre", "id": { "authority": "EPSG", "code": 8807 } } ] }, "coordinate_system": { "subtype": "Cartesian", "axis": [ { "name": "Easting", "abbreviation": "E", "direction": "east", "unit": "metre" }, { "name": "Northing", "abbreviation": "N", "direction": "north", "unit": "metre" } ] }, "id": { "authority": "EPSG", "code": 2021 } }, "target_crs": { "type": "GeographicCRS", "name": "NAD83", "datum": { "type": "GeodeticReferenceFrame", "name": "North American Datum 1983", "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": 4269 } }, "transformation": { "name": "NAD27(76) to NAD83 (1)", "method": { "name": "NTv2", "id": { "authority": "EPSG", "code": 9615 } }, "parameters": [ { "name": "Latitude and longitude difference file", "value": "May76v20.gsb", "id": { "authority": "EPSG", "code": 8656 } } ], "id": { "authority": "EPSG", "code": 1463 } } }
Definition: Mapnik
<?xml version="1.0" encoding="utf-8"?> <Map srs="+proj=tmerc +lat_0=0 +lon_0=-81 +k=0.9999 +x_0=304800 +y_0=0 +ellps=clrk66 +units=m +no_defs +type=crs"> <Layer srs="+proj=tmerc +lat_0=0 +lon_0=-81 +k=0.9999 +x_0=304800 +y_0=0 +ellps=clrk66 +units=m +no_defs +type=crs"> </Layer> </Map>