EPSG:26731

NAD27 / Alaska zone 1

Transform Get position on a map

Available transformations
to EPSG:4326
EPSG:4326 - WGS 84

Selected transformation

Method: Geocentric translations (geog2D domain)

Remarks: Developed by John E Chance and Associates. Replaced by NAD27 to WGS 84 (79) (tfm code 15851).

Information source: Fugro Chance

Revision date: 2020-03-14

Attributes

Unit: US survey foot

Geodetic CRS: NAD27

Datum: North American Datum 1927

Ellipsoid: Clarke 1866

Prime meridian: Greenwich

Data source: EPSG

Revision date: 1995-06-02

Scope: Engineering survey, topographic mapping.

Area of use: United States (USA) - Alaska - east of 141°W; i.e. Panhandle.

Coordinate system: Cartesian 2D CS. Axes: easting, northing (X,Y). Orientations: east, north. UoM: ftUS.

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SimpleMap

Center coordinates
16342728.9 -5359252.13

Projected bounds:
14809569.52 -6677860.76
17930075.55 -3989728.07

WGS84 bounds:
-95.0 25.61
-87.25 30.23

United States (USA) - offshore Gulf of Mexico (GoM) between approximately 95°W and 87°15'W - protraction areas High Island (including all additions and extensions), Sabine Pass, West Cameron (including west and south additions), East Cameron (including south addition), Vermillion (including south addition), South Marsh Island (including north and south additions), Eugene Island (including south addition), Ship Shoal (including south addition), South Timbalier (including south addition), Grand Isle (including south addition), West Delta (including south addition), South Pass (including south and east additions), Main Pass (including south and east addition), Breton Sound, Chandeleur (including east addition), Mobile, Viosca Knoll, Mississippi Canyon, Atwater Valley, Lund, Lund South, Ewing Bank, Green Canyon, Walker Ridge, Amery Terrace, Garden Banks, Keathley Canyon and Sigsbee Escarpment. Also for protraction areas Galveston (including south addition), East Breaks and Aliminos Canyon - east of 95°W; for protraction areas Pensacola, Destin Dome, Desoto Canyon, Lloyd Ridge, Henderson and Florida Plain - west of 87°15'W.
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Definition: OGC Well Known Text

PROJCS["NAD27 / Alaska zone 1",
    GEOGCS["NAD27",
        DATUM["North_American_Datum_1927",
            SPHEROID["Clarke 1866",6378206.4,294.978698213898],
            TOWGS84[-7,151,175,0,0,0,0]],
        PRIMEM["Greenwich",0,
            AUTHORITY["EPSG","8901"]],
        UNIT["degree",0.0174532925199433,
            AUTHORITY["EPSG","9122"]],
        AUTHORITY["EPSG","4267"]],
    PROJECTION["Hotine_Oblique_Mercator"],
    PARAMETER["latitude_of_center",57],
    PARAMETER["longitude_of_center",-133.666666666667],
    PARAMETER["azimuth",323.130102361111],
    PARAMETER["rectified_grid_angle",323.130102361111],
    PARAMETER["scale_factor",0.9999],
    PARAMETER["false_easting",16404166.67],
    PARAMETER["false_northing",-16404166.67],
    UNIT["US survey foot",0.304800609601219],
    AXIS["Easting",EAST],
    AXIS["Northing",NORTH],
    AUTHORITY["EPSG","26731"]]

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["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["Transformation from unknown to WGS84",
        METHOD["Position Vector transformation (geog2D domain)",
            ID["EPSG",9606]],
        PARAMETER["X-axis translation",-7,
            ID["EPSG",8605]],
        PARAMETER["Y-axis translation",151,
            ID["EPSG",8606]],
        PARAMETER["Z-axis translation",175,
            ID["EPSG",8607]],
        PARAMETER["X-axis rotation",0,
            ID["EPSG",8608]],
        PARAMETER["Y-axis rotation",0,
            ID["EPSG",8609]],
        PARAMETER["Z-axis rotation",0,
            ID["EPSG",8610]],
        PARAMETER["Scale difference",1,
            ID["EPSG",8611]]]]

Definition: ESRI Well Known Text

PROJCS["NAD_1927_StatePlane_Alaska_1_FIPS_5001",
    GEOGCS["GCS_North_American_1927",
        DATUM["D_North_American_1927",
            SPHEROID["Clarke_1866",6378206.4,294.978698213898]],
        PRIMEM["Greenwich",0.0],
        UNIT["Degree",0.0174532925199433]],
    PROJECTION["Hotine_Oblique_Mercator_Azimuth_Natural_Origin"],
    PARAMETER["False_Easting",16404166.67],
    PARAMETER["False_Northing",-16404166.67],
    PARAMETER["Scale_Factor",0.9999],
    PARAMETER["Azimuth",-36.869897638889],
    PARAMETER["Longitude_Of_Center",-133.666666666667],
    PARAMETER["Latitude_Of_Center",57.0],
    UNIT["US survey foot",0.304800609601219]]

Definition: PROJ.4

+proj=omerc +no_uoff +lat_0=57 +lonc=-133.666666666667 +alpha=323.130102361111 +gamma=323.130102361111 +k=0.9999 +x_0=5000000.001016 +y_0=-5000000.001016 +ellps=clrk66 +towgs84=-7,151,175,0,0,0,0 +units=us-ft +no_defs +type=crs

Definition: JavaScript (Proj4js) 

proj4.defs("EPSG:26731","+proj=omerc +no_uoff +lat_0=57 +lonc=-133.666666666667 +alpha=323.130102361111 +gamma=323.130102361111 +k=0.9999 +x_0=5000000.001016 +y_0=-5000000.001016 +ellps=clrk66 +towgs84=-7,151,175,0,0,0,0 +units=us-ft +no_defs +type=crs");

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": "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": "Transformation from unknown to WGS84",
        "method": {
            "name": "Position Vector transformation (geog2D domain)",
            "id": {
                "authority": "EPSG",
                "code": 9606
            }
        },
        "parameters": [
            {
                "name": "X-axis translation",
                "value": -7,
                "unit": "metre",
                "id": {
                    "authority": "EPSG",
                    "code": 8605
                }
            },
            {
                "name": "Y-axis translation",
                "value": 151,
                "unit": "metre",
                "id": {
                    "authority": "EPSG",
                    "code": 8606
                }
            },
            {
                "name": "Z-axis translation",
                "value": 175,
                "unit": "metre",
                "id": {
                    "authority": "EPSG",
                    "code": 8607
                }
            },
            {
                "name": "X-axis rotation",
                "value": 0,
                "unit": {
                    "type": "AngularUnit",
                    "name": "arc-second",
                    "conversion_factor": 4.84813681109536e-06
                },
                "id": {
                    "authority": "EPSG",
                    "code": 8608
                }
            },
            {
                "name": "Y-axis rotation",
                "value": 0,
                "unit": {
                    "type": "AngularUnit",
                    "name": "arc-second",
                    "conversion_factor": 4.84813681109536e-06
                },
                "id": {
                    "authority": "EPSG",
                    "code": 8609
                }
            },
            {
                "name": "Z-axis rotation",
                "value": 0,
                "unit": {
                    "type": "AngularUnit",
                    "name": "arc-second",
                    "conversion_factor": 4.84813681109536e-06
                },
                "id": {
                    "authority": "EPSG",
                    "code": 8610
                }
            },
            {
                "name": "Scale difference",
                "value": 0,
                "unit": {
                    "type": "ScaleUnit",
                    "name": "parts per million",
                    "conversion_factor": 1e-06
                },
                "id": {
                    "authority": "EPSG",
                    "code": 8611
                }
            }
        ]
    }
}

Definition: GeoServer

26731=PROJCS["NAD27 / Alaska zone 1",GEOGCS["NAD27",DATUM["North_American_Datum_1927",SPHEROID["Clarke 1866",6378206.4,294.978698213898],TOWGS84[-7,151,175,0,0,0,0]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4267"]],PROJECTION["Hotine_Oblique_Mercator"],PARAMETER["latitude_of_center",57],PARAMETER["longitude_of_center",-133.666666666667],PARAMETER["azimuth",323.130102361111],PARAMETER["rectified_grid_angle",323.130102361111],PARAMETER["scale_factor",0.9999],PARAMETER["false_easting",16404166.67],PARAMETER["false_northing",-16404166.67],UNIT["US survey foot",0.304800609601219],AXIS["Easting",EAST],AXIS["Northing",NORTH],AUTHORITY["EPSG","26731"]]

Definition: MapServer - MAPfile

PROJECTION
	"proj=omerc"
	"no_uoff"
	"lat_0=57"
	"lonc=-133.666666666667"
	"alpha=323.130102361111"
	"gamma=323.130102361111"
	"k=0.9999"
	"x_0=5000000.001016"
	"y_0=-5000000.001016"
	"ellps=clrk66"
	"towgs84=-7,151,175,0,0,0,0"
	"units=us-ft"
	"no_defs"
	"type=crs"
END

Definition: Mapnik

<?xml version="1.0" encoding="utf-8"?>
<Map srs="+proj=omerc +no_uoff +lat_0=57 +lonc=-133.666666666667 +alpha=323.130102361111 +gamma=323.130102361111 +k=0.9999 +x_0=5000000.001016 +y_0=-5000000.001016 +ellps=clrk66 +towgs84=-7,151,175,0,0,0,0 +units=us-ft +no_defs +type=crs">
	<Layer srs="+proj=omerc +no_uoff +lat_0=57 +lonc=-133.666666666667 +alpha=323.130102361111 +gamma=323.130102361111 +k=0.9999 +x_0=5000000.001016 +y_0=-5000000.001016 +ellps=clrk66 +towgs84=-7,151,175,0,0,0,0 +units=us-ft +no_defs +type=crs">
	</Layer>
</Map>

Definition: SQL (PostGIS)

INSERT into spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext) values ( 26731, 'EPSG', 26731, '+proj=omerc +no_uoff +lat_0=57 +lonc=-133.666666666667 +alpha=323.130102361111 +gamma=323.130102361111 +k=0.9999 +x_0=5000000.001016 +y_0=-5000000.001016 +ellps=clrk66 +towgs84=-7,151,175,0,0,0,0 +units=us-ft +no_defs +type=crs', 'PROJCS["NAD27 / Alaska zone 1",GEOGCS["NAD27",DATUM["North_American_Datum_1927",SPHEROID["Clarke 1866",6378206.4,294.978698213898],TOWGS84[-7,151,175,0,0,0,0]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4267"]],PROJECTION["Hotine_Oblique_Mercator"],PARAMETER["latitude_of_center",57],PARAMETER["longitude_of_center",-133.666666666667],PARAMETER["azimuth",323.130102361111],PARAMETER["rectified_grid_angle",323.130102361111],PARAMETER["scale_factor",0.9999],PARAMETER["false_easting",16404166.67],PARAMETER["false_northing",-16404166.67],UNIT["US survey foot",0.304800609601219],AXIS["Easting",EAST],AXIS["Northing",NORTH],AUTHORITY["EPSG","26731"]]');