conus.las conus.los
Uses NADCON method which expects longitudes positive west; EPSG GeogCRS NAD27 (code 4267) and NAD83 (code 4269) have longitudes positive east. For application in Gulf of Mexico refer to IOGP report 373-26.
US Coast & Geodetic Survey www.ngs.noaa.gov
2021-10-18
-4988262.61 14083591.46
-18342421.79 8638909.52
4760698.61 23052748.22
-129.17 23.81
-65.69 49.38
Definition: OGC Well Known Text 2 (2019)
BOUNDCRS[ SOURCECRS[ PROJCRS["NAD27 / BLM 18N (ftUS)", 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["BLM zone 18N (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",-75, 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 78°W and 72°W onshore and offshore - Connecticut; Delaware; Maryland; Massachusetts; New Hampshire; New Jersey; New York; North Carolina; Pennsylvania; Virginia; Vermont."], BBOX[28.28,-78,45.03,-72]], ID["EPSG",4418]]], TARGETCRS[ GEOGCRS["NAD83", DATUM["North American Datum 1983", ELLIPSOID["GRS 1980",6378137,298.257222101, 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["North America - onshore and offshore: Canada - Alberta; British Columbia; Manitoba; New Brunswick; Newfoundland and Labrador; Northwest Territories; Nova Scotia; Nunavut; Ontario; Prince Edward Island; Quebec; Saskatchewan; Yukon. Puerto Rico. United States (USA) - Alabama; Alaska; Arizona; Arkansas; California; Colorado; Connecticut; Delaware; Florida; Georgia; Hawaii; Idaho; Illinois; Indiana; Iowa; Kansas; Kentucky; Louisiana; Maine; Maryland; Massachusetts; Michigan; Minnesota; Mississippi; Missouri; Montana; Nebraska; Nevada; New Hampshire; New Jersey; New Mexico; New York; North Carolina; North Dakota; Ohio; Oklahoma; Oregon; Pennsylvania; Rhode Island; South Carolina; South Dakota; Tennessee; Texas; Utah; Vermont; Virginia; Washington; West Virginia; Wisconsin; Wyoming. US Virgin Islands. British Virgin Islands."], BBOX[14.92,167.65,86.45,-40.73]], ID["EPSG",4269]]], ABRIDGEDTRANSFORMATION["NAD27 to NAD83 (1)", METHOD["NADCON", ID["EPSG",9613]], PARAMETERFILE["Latitude difference file","conus.las"], PARAMETERFILE["Longitude difference file","conus.los"], USAGE[ SCOPE["Transformation of coordinates at 0.2m level of accuracy."], AREA["United States (USA) - CONUS including EEZ - onshore and offshore - Alabama; Arizona; Arkansas; California; Colorado; Connecticut; Delaware; Florida; Georgia; Idaho; Illinois; Indiana; Iowa; Kansas; Kentucky; Louisiana; Maine; Maryland; Massachusetts; Michigan; Minnesota; Mississippi; Missouri; Montana; Nebraska; Nevada; New Hampshire; New Jersey; New Mexico; New York; North Carolina; North Dakota; Ohio; Oklahoma; Oregon; Pennsylvania; Rhode Island; South Carolina; South Dakota; Tennessee; Texas; Utah; Vermont; Virginia; Washington; West Virginia; Wisconsin; Wyoming. US Gulf of Mexico (GoM) OCS."], BBOX[23.81,-129.17,49.38,-65.69]], ID["EPSG",1241], REMARK["Uses NADCON method which expects longitudes positive west; EPSG GeogCRS NAD27 (code 4267) and NAD83 (code 4269) have longitudes positive east. For application in Gulf of Mexico refer to IOGP report 373-26."]]]
Definition: JSON
{ "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json", "type": "BoundCRS", "source_crs": { "type": "ProjectedCRS", "name": "NAD27 / BLM 18N (ftUS)", "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": "BLM zone 18N (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": -75, "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 } } ] }, "id": { "authority": "EPSG", "code": 4418 } }, "target_crs": { "type": "GeographicCRS", "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 } }, "transformation": { "name": "NAD27 to NAD83 (1)", "method": { "name": "NADCON", "id": { "authority": "EPSG", "code": 9613 } }, "parameters": [ { "name": "Latitude difference file", "value": "conus.las", "id": { "authority": "EPSG", "code": 8657 } }, { "name": "Longitude difference file", "value": "conus.los", "id": { "authority": "EPSG", "code": 8658 } } ], "id": { "authority": "EPSG", "code": 1241 } } }
Definition: Mapnik
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