EPSG:4609

NAD27(CGQ77)

Selected transformation

Method: NTv2

Grid Files: CQ77NA83.GSB

Remarks: Parameter file is from NAD27(CGQ77) to NAD83 (2) (code 1575) assuming that NAD83(CSRS)v2 is equivalent to WGS 84 within the accuracy of the transformation.

Information source: OGP

Revision date: 2021-11-04

Attributes

Unit: degree (supplier to define representation)

Geodetic CRS: NAD27(CGQ77)

Datum: North American Datum 1927 (CGQ77)

Ellipsoid: Clarke 1866

Prime meridian: Greenwich

Data source: EPSG

Revision date: 2019-09-17

Scope: Geodesy.

Remarks: Note: this CRS includes longitudes which are POSITIVE EAST.

Area of use: Canada - Quebec.

Coordinate system: Ellipsoidal 2D CS. Axes: latitude, longitude. Orientations: north, east. UoM: degree

Center coordinates
-68.48 53.8

WGS84 bounds:
-79.85 44.99
-57.1 62.62

Canada - Quebec.
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Definition: OGC Well Known Text

GEOGCS["NAD27(CGQ77)",
    DATUM["North_American_Datum_1927_CGQ77",
        SPHEROID["Clarke 1866",6378206.4,294.978698213898],
        EXTENSION["PROJ4_GRIDS","CQ77NA83.GSB"]],
    PRIMEM["Greenwich",0,
        AUTHORITY["EPSG","8901"]],
    UNIT["degree",0.0174532925199433,
        AUTHORITY["EPSG","9122"]],
    AUTHORITY["EPSG","4609"]]

Definition: OGC Well Known Text 2 (2019)

GEOGCRS["NAD27(CGQ77)",
    DATUM["North American Datum 1927 (CGQ77)",
        ELLIPSOID["Clarke 1866",6378206.4,294.978698213898,
            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["Canada - Quebec."],
        BBOX[44.99,-79.85,62.62,-57.1]],
    ID["EPSG",4609]]

Definition: ESRI Well Known Text

GEOGCS["GCS_NAD_1927_CGQ77",
    DATUM["D_NAD_1927_CGQ77",
        SPHEROID["Clarke_1866",6378206.4,294.978698213898],
        EXTENSION["PROJ4_GRIDS","CQ77NA83.GSB"]],
    PRIMEM["Greenwich",0.0],
    UNIT["Degree",0.0174532925199433]]

Definition: PROJ.4

+proj=longlat +ellps=clrk66 +nadgrids=CQ77NA83.GSB +no_defs +type=crs

Definition: JavaScript (Proj4js)

proj4.defs("EPSG:4609","+proj=longlat +ellps=clrk66 +nadgrids=CQ77NA83.GSB +no_defs +type=crs");

Definition: JSON

{
    "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json",
    "type": "GeographicCRS",
    "name": "NAD27(CGQ77)",
    "datum": {
        "type": "GeodeticReferenceFrame",
        "name": "North American Datum 1927 (CGQ77)",
        "ellipsoid": {
            "name": "Clarke 1866",
            "semi_major_axis": 6378206.4,
            "inverse_flattening": 294.978698213898
        }
    },
    "coordinate_system": {
        "subtype": "ellipsoidal",
        "axis": [
            {
                "name": "Geodetic latitude",
                "abbreviation": "Lat",
                "direction": "north",
                "unit": "degree"
            },
            {
                "name": "Geodetic longitude",
                "abbreviation": "Lon",
                "direction": "east",
                "unit": "degree"
            }
        ]
    },
    "scope": "Geodesy.",
    "area": "Canada - Quebec.",
    "bbox": {
        "south_latitude": 44.99,
        "west_longitude": -79.85,
        "north_latitude": 62.62,
        "east_longitude": -57.1
    },
    "id": {
        "authority": "EPSG",
        "code": 4609
    }
}

Definition: GeoServer

4609=GEOGCS["NAD27(CGQ77)",DATUM["North_American_Datum_1927_CGQ77",SPHEROID["Clarke 1866",6378206.4,294.978698213898],EXTENSION["PROJ4_GRIDS","CQ77NA83.GSB"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4609"]]

Definition: MapServer - MAPfile

PROJECTION
	"proj=longlat"
	"ellps=clrk66"
	"nadgrids=CQ77NA83.GSB"
	"no_defs"
	"type=crs"
END

Definition: Mapnik

<?xml version="1.0" encoding="utf-8"?>
<Map srs="+proj=longlat +ellps=clrk66 +nadgrids=CQ77NA83.GSB +no_defs +type=crs">
	<Layer srs="+proj=longlat +ellps=clrk66 +nadgrids=CQ77NA83.GSB +no_defs +type=crs">
	</Layer>
</Map>

Definition: SQL (PostGIS)

INSERT into spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext) values ( 4609, 'EPSG', 4609, '+proj=longlat +ellps=clrk66 +nadgrids=CQ77NA83.GSB +no_defs +type=crs', 'GEOGCS["NAD27(CGQ77)",DATUM["North_American_Datum_1927_CGQ77",SPHEROID["Clarke 1866",6378206.4,294.978698213898],EXTENSION["PROJ4_GRIDS","CQ77NA83.GSB"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4609"]]');