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)

BOUNDCRS[
    SOURCECRS[
        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]]],
    TARGETCRS[
        GEOGCRS["WGS 84",
            ENSEMBLE["World Geodetic System 1984 ensemble",
                MEMBER["World Geodetic System 1984 (Transit)"],
                MEMBER["World Geodetic System 1984 (G730)"],
                MEMBER["World Geodetic System 1984 (G873)"],
                MEMBER["World Geodetic System 1984 (G1150)"],
                MEMBER["World Geodetic System 1984 (G1674)"],
                MEMBER["World Geodetic System 1984 (G1762)"],
                MEMBER["World Geodetic System 1984 (G2139)"],
                ELLIPSOID["WGS 84",6378137,298.257223563,
                    LENGTHUNIT["metre",1]],
                ENSEMBLEACCURACY[2.0]],
            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["World."],
                BBOX[-90,-180,90,180]],
            ID["EPSG",4326]]],
    ABRIDGEDTRANSFORMATION["NAD27(CGQ77) to WGS 84 (3)",
        METHOD["NTv2",
            ID["EPSG",9615]],
        PARAMETERFILE["Latitude and longitude difference file","CQ77NA83.GSB"],
        USAGE[
            SCOPE["(null/copy) Approximation for medium and low accuracy applications assuming equality between plate-fixed static and earth-fixed dynamic CRSs, ignoring static/dynamic CRS differences."],
            AREA["Canada - Quebec."],
            BBOX[44.99,-79.85,62.62,-57.1]],
        ID["EPSG",1691],
        REMARK["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."]]]

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": "BoundCRS",
    "source_crs": {
        "type": "GeographicCRS",
        "name": "NAD27(CGQ77)",
        "datum": {
            "type": "GeodeticReferenceFrame",
            "name": "North American Datum 1927 (CGQ77)",
            "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": 4609
        }
    },
    "target_crs": {
        "type": "GeographicCRS",
        "name": "WGS 84",
        "datum_ensemble": {
            "name": "World Geodetic System 1984 ensemble",
            "members": [
                {
                    "name": "World Geodetic System 1984 (Transit)",
                    "id": {
                        "authority": "EPSG",
                        "code": 1166
                    }
                },
                {
                    "name": "World Geodetic System 1984 (G730)",
                    "id": {
                        "authority": "EPSG",
                        "code": 1152
                    }
                },
                {
                    "name": "World Geodetic System 1984 (G873)",
                    "id": {
                        "authority": "EPSG",
                        "code": 1153
                    }
                },
                {
                    "name": "World Geodetic System 1984 (G1150)",
                    "id": {
                        "authority": "EPSG",
                        "code": 1154
                    }
                },
                {
                    "name": "World Geodetic System 1984 (G1674)",
                    "id": {
                        "authority": "EPSG",
                        "code": 1155
                    }
                },
                {
                    "name": "World Geodetic System 1984 (G1762)",
                    "id": {
                        "authority": "EPSG",
                        "code": 1156
                    }
                },
                {
                    "name": "World Geodetic System 1984 (G2139)",
                    "id": {
                        "authority": "EPSG",
                        "code": 1309
                    }
                }
            ],
            "ellipsoid": {
                "name": "WGS 84",
                "semi_major_axis": 6378137,
                "inverse_flattening": 298.257223563
            },
            "accuracy": "2.0",
            "id": {
                "authority": "EPSG",
                "code": 6326
            }
        },
        "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": 4326
        }
    },
    "transformation": {
        "name": "NAD27(CGQ77) to WGS 84 (3)",
        "method": {
            "name": "NTv2",
            "id": {
                "authority": "EPSG",
                "code": 9615
            }
        },
        "parameters": [
            {
                "name": "Latitude and longitude difference file",
                "value": "CQ77NA83.GSB",
                "id": {
                    "authority": "EPSG",
                    "code": 8656
                }
            }
        ],
        "id": {
            "authority": "EPSG",
            "code": 1691
        }
    }
}

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"]]');