Derived at IGN monument CFP19 using Transit. Can be implemented as a single 7-param Position Vector transformation with parameter values of dX=-156.5m dY=-87.2m dZ=+287.8m; rX=rY=0 rZ=+0.814sec; dS=-0.38ppm.
2020-03-14
degree (supplier to define representation)
EPSG
"Le System Geodesique Nord-Sahara"; IGN Paris
2012-04-18
Geodesy.
Sometimes incorrectly referred to as Voirol Unifie 1960: this is NOT a GeogCRS but two projected CRSs based on Nord Sahara 1959 (codes 30791-92). Strictly applicable only to north of 32°N but extended southwards non-homogoneously by oil industry.
Algeria - onshore and offshore.
Ellipsoidal 2D CS. Axes: latitude, longitude. Orientations: north, east. UoM: degree
Definition: OGC Well Known Text 2 (2019)
BOUNDCRS[ SOURCECRS[ BOUNDCRS[ SOURCECRS[ GEOGCRS["Nord Sahara 1959", DATUM["Nord Sahara 1959", ELLIPSOID["Clarke 1880 (RGS)",6378249.145,293.465, 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]], ID["EPSG",4307]]], TARGETCRS[ GEOGCRS["WGS 72BE", DYNAMIC[ FRAMEEPOCH[1972]], DATUM["WGS 72 Transit Broadcast Ephemeris", ELLIPSOID["WGS 72",6378135,298.26, 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]], ID["EPSG",4324]]], ABRIDGEDTRANSFORMATION["Nord Sahara 1959 to WGS 72BE (1)", METHOD["Geocentric translations (geog2D domain)", ID["EPSG",9603]], PARAMETER["X-axis translation",-156.5, ID["EPSG",8605]], PARAMETER["Y-axis translation",-87.2, ID["EPSG",8606]], PARAMETER["Z-axis translation",285.9, ID["EPSG",8607]], ID["EPSG",1560]]]], 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["WGS 72BE to WGS 84 (1)", METHOD["Position Vector transformation (geog2D domain)", ID["EPSG",9606]], PARAMETER["X-axis translation",0, ID["EPSG",8605]], PARAMETER["Y-axis translation",0, ID["EPSG",8606]], PARAMETER["Z-axis translation",1.9, ID["EPSG",8607]], PARAMETER["X-axis rotation",0, ID["EPSG",8608]], PARAMETER["Y-axis rotation",0, ID["EPSG",8609]], PARAMETER["Z-axis rotation",0.814, ID["EPSG",8610]], PARAMETER["Scale difference",0.99999962, ID["EPSG",8611]], USAGE[ SCOPE["Geodesy."], AREA["World. Vietnam - offshore."], BBOX[-90,-180,90,180]], ID["EPSG",1240]]]
Definition: JSON
{ "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json", "type": "BoundCRS", "source_crs": { "type": "BoundCRS", "source_crs": { "type": "GeographicCRS", "name": "Nord Sahara 1959", "datum": { "type": "GeodeticReferenceFrame", "name": "Nord Sahara 1959", "ellipsoid": { "name": "Clarke 1880 (RGS)", "semi_major_axis": 6378249.145, "inverse_flattening": 293.465 } }, "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": 4307 } }, "target_crs": { "type": "GeographicCRS", "name": "WGS 72BE", "datum": { "type": "DynamicGeodeticReferenceFrame", "name": "WGS 72 Transit Broadcast Ephemeris", "frame_reference_epoch": 1972, "ellipsoid": { "name": "WGS 72", "semi_major_axis": 6378135, "inverse_flattening": 298.26 } }, "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": 4324 } }, "transformation": { "name": "Nord Sahara 1959 to WGS 72BE (1)", "method": { "name": "Geocentric translations (geog2D domain)", "id": { "authority": "EPSG", "code": 9603 } }, "parameters": [ { "name": "X-axis translation", "value": -156.5, "unit": "metre", "id": { "authority": "EPSG", "code": 8605 } }, { "name": "Y-axis translation", "value": -87.2, "unit": "metre", "id": { "authority": "EPSG", "code": 8606 } }, { "name": "Z-axis translation", "value": 285.9, "unit": "metre", "id": { "authority": "EPSG", "code": 8607 } } ], "id": { "authority": "EPSG", "code": 1560 } } }, "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": "WGS 72BE to WGS 84 (1)", "source_crs": { "type": "GeographicCRS", "name": "WGS 72BE", "datum": { "type": "DynamicGeodeticReferenceFrame", "name": "WGS 72 Transit Broadcast Ephemeris", "frame_reference_epoch": 1972, "ellipsoid": { "name": "WGS 72", "semi_major_axis": 6378135, "inverse_flattening": 298.26 } }, "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": 4324 } }, "method": { "name": "Position Vector transformation (geog2D domain)", "id": { "authority": "EPSG", "code": 9606 } }, "parameters": [ { "name": "X-axis translation", "value": 0, "unit": "metre", "id": { "authority": "EPSG", "code": 8605 } }, { "name": "Y-axis translation", "value": 0, "unit": "metre", "id": { "authority": "EPSG", "code": 8606 } }, { "name": "Z-axis translation", "value": 1.9, "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": 0.814, "unit": { "type": "AngularUnit", "name": "arc-second", "conversion_factor": 4.84813681109536e-06 }, "id": { "authority": "EPSG", "code": 8610 } }, { "name": "Scale difference", "value": -0.38, "unit": { "type": "ScaleUnit", "name": "parts per million", "conversion_factor": 1e-06 }, "id": { "authority": "EPSG", "code": 8611 } } ], "id": { "authority": "EPSG", "code": 1240 } } }
Definition: Mapnik
<?xml version="1.0" encoding="utf-8"?> <Map srs="+proj=longlat +a=6378249.145 +rf=293.465 +towgs84=0,0,1.9,0,0,0.814,-0.38 +no_defs +type=crs"> <Layer srs="+proj=longlat +a=6378249.145 +rf=293.465 +towgs84=0,0,1.9,0,0,0.814,-0.38 +no_defs +type=crs"> </Layer> </Map>