The gridded difference file AB_CSRS.DAC in STEP 1 will need to be renamed to AB_CSRS.gsb to run in some software suites. Formats identical, but AB file is provincial fit only. Geodetic Control Section; Land and Forest Svc; Alberta Environment; http://www.gov.ab.ca/env/land/dos/ or email to
2000-10-19
10609567.98 22864640.03
8470567.67 20349263.23
13023713.63 25212471.82
-120.0 48.99
-109.98 60.0
Definition: OGC Well Known Text
PROJCS["NAD83 / BLM 4N (ftUS)", GEOGCS["NAD83", DATUM["North_American_Datum_1983", SPHEROID["GRS 1980",6378137,298.257222101, AUTHORITY["EPSG","7019"]], AUTHORITY["EPSG","6269"]], PRIMEM["Greenwich",0, AUTHORITY["EPSG","8901"]], UNIT["degree",0.0174532925199433, AUTHORITY["EPSG","9122"]], AUTHORITY["EPSG","4269"]], PROJECTION["Transverse_Mercator"], PARAMETER["latitude_of_origin",0], PARAMETER["central_meridian",-159], PARAMETER["scale_factor",0.9996], PARAMETER["false_easting",1640416.67], PARAMETER["false_northing",0], UNIT["US survey foot",0.304800609601219, AUTHORITY["EPSG","9003"]], AXIS["Easting",EAST], AXIS["Northing",NORTH], AUTHORITY["EPSG","4424"]]
Definition: OGC Well Known Text 2 (2019)
PROJCRS["NAD83 / BLM 4N (ftUS)", BASEGEOGCRS["NAD83", DATUM["North American Datum 1983", ELLIPSOID["GRS 1980",6378137,298.257222101, LENGTHUNIT["metre",1]]], PRIMEM["Greenwich",0, ANGLEUNIT["degree",0.0174532925199433]], ID["EPSG",4269]], CONVERSION["BLM zone 4N (US survey foot)", METHOD["Transverse Mercator", ID["EPSG",9807]], PARAMETER["Latitude of natural origin",0, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8801]], PARAMETER["Longitude of natural origin",-159, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8802]], PARAMETER["Scale factor at natural origin",0.9996, SCALEUNIT["unity",1], ID["EPSG",8805]], PARAMETER["False easting",1640416.67, LENGTHUNIT["US survey foot",0.304800609601219], ID["EPSG",8806]], PARAMETER["False northing",0, 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["No official usage."], AREA["United States (USA) - between 162°W and 156°W - Alaska and offshore continental shelf (OCS)."], BBOX[50.98,-162,74.71,-155.99]], ID["EPSG",4424]]
Definition: ESRI Well Known Text
PROJCS["NAD_1983_BLM_Zone_4N", GEOGCS["GCS_North_American_1983", DATUM["D_North_American_1983", SPHEROID["GRS_1980",6378137.0,298.257222101]], PRIMEM["Greenwich",0.0], UNIT["Degree",0.0174532925199433]], PROJECTION["Transverse_Mercator"], PARAMETER["False_Easting",1640416.67], PARAMETER["False_Northing",0.0], PARAMETER["Central_Meridian",-159.0], PARAMETER["Scale_Factor",0.9996], PARAMETER["Latitude_Of_Origin",0.0], UNIT["US survey foot",0.304800609601219]]
Definition: JSON
{ "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json", "type": "ProjectedCRS", "name": "NAD83 / BLM 4N (ftUS)", "base_crs": { "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 } }, "conversion": { "name": "BLM zone 4N (US survey foot)", "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": -159, "unit": "degree", "id": { "authority": "EPSG", "code": 8802 } }, { "name": "Scale factor at natural origin", "value": 0.9996, "unit": "unity", "id": { "authority": "EPSG", "code": 8805 } }, { "name": "False easting", "value": 1640416.67, "unit": { "type": "LinearUnit", "name": "US survey foot", "conversion_factor": 0.304800609601219 }, "id": { "authority": "EPSG", "code": 8806 } }, { "name": "False northing", "value": 0, "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 } } ] }, "scope": "No official usage.", "area": "United States (USA) - between 162°W and 156°W - Alaska and offshore continental shelf (OCS).", "bbox": { "south_latitude": 50.98, "west_longitude": -162, "north_latitude": 74.71, "east_longitude": -155.99 }, "id": { "authority": "EPSG", "code": 4424 } }
Definition: GeoServer
4424=PROJCS["NAD83 / BLM 4N (ftUS)",GEOGCS["NAD83",DATUM["North_American_Datum_1983",SPHEROID["GRS 1980",6378137,298.257222101,AUTHORITY["EPSG","7019"]],AUTHORITY["EPSG","6269"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4269"]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin",0],PARAMETER["central_meridian",-159],PARAMETER["scale_factor",0.9996],PARAMETER["false_easting",1640416.67],PARAMETER["false_northing",0],UNIT["US survey foot",0.304800609601219,AUTHORITY["EPSG","9003"]],AXIS["Easting",EAST],AXIS["Northing",NORTH],AUTHORITY["EPSG","4424"]]
Definition: Mapnik
<?xml version="1.0" encoding="utf-8"?> <Map srs="+proj=tmerc +lat_0=0 +lon_0=-159 +k=0.9996 +x_0=500000.001016002 +y_0=0 +datum=NAD83 +units=us-ft +no_defs +type=crs"> <Layer srs="+proj=tmerc +lat_0=0 +lon_0=-159 +k=0.9996 +x_0=500000.001016002 +y_0=0 +datum=NAD83 +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 ( 4424, 'EPSG', 4424, '+proj=tmerc +lat_0=0 +lon_0=-159 +k=0.9996 +x_0=500000.001016002 +y_0=0 +datum=NAD83 +units=us-ft +no_defs +type=crs', 'PROJCS["NAD83 / BLM 4N (ftUS)",GEOGCS["NAD83",DATUM["North_American_Datum_1983",SPHEROID["GRS 1980",6378137,298.257222101,AUTHORITY["EPSG","7019"]],AUTHORITY["EPSG","6269"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4269"]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin",0],PARAMETER["central_meridian",-159],PARAMETER["scale_factor",0.9996],PARAMETER["false_easting",1640416.67],PARAMETER["false_northing",0],UNIT["US survey foot",0.304800609601219,AUTHORITY["EPSG","9003"]],AXIS["Easting",EAST],AXIS["Northing",NORTH],AUTHORITY["EPSG","4424"]]');