EPSG:4122

BOUNDCRS[
    SOURCECRS[
        GEOGCRS["ATS77",
            DATUM["Average Terrestrial System 1977",
                ELLIPSOID["Average Terrestrial System 1977",6378135,298.257,
                    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 - New Brunswick; Nova Scotia; Prince Edward Island."],
                BBOX[43.41,-69.05,48.07,-59.73]],
            ID["EPSG",4122],
            REMARK["In use from 1979. To be phased out in late 1990's."]]],
    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[14.92,167.65,86.46,-40.73]],
            ID["EPSG",4269],
            REMARK["Longitude is POSITIVE EAST. The adjustment included connections to Greenland and Mexico but the system was not adopted there. For applications with an accuracy of better than 1m replaced by NAD83(HARN) in the US and PRVI and by NAD83(CSRS) in Canada."]]],
    ABRIDGEDTRANSFORMATION["ATS77 to NAD83 (1)",
        METHOD["NTv2",
            ID["EPSG",9615]],
        PARAMETERFILE["Latitude and longitude difference file","GS7783.GSB"],
        USAGE[
            SCOPE["Geodesy."],
            AREA["Canada - Nova Scotia onshore."],
            BBOX[43.41,-66.28,47.08,-59.73]],
        ID["EPSG",9105]]]

proj4.defs("EPSG:4122","+proj=longlat +a=6378135 +rf=298.257 +no_defs +type=crs");

{
    "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json",
    "type": "BoundCRS",
    "source_crs": {
        "type": "GeographicCRS",
        "name": "ATS77",
        "datum": {
            "type": "GeodeticReferenceFrame",
            "name": "Average Terrestrial System 1977",
            "ellipsoid": {
                "name": "Average Terrestrial System 1977",
                "semi_major_axis": 6378135,
                "inverse_flattening": 298.257
            }
        },
        "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": 4122
        },
        "remarks": "In use from 1979. To be phased out in late 1990's."
    },
    "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
        },
        "remarks": "Longitude is POSITIVE EAST. The adjustment included connections to Greenland and Mexico but the system was not adopted there. For applications with an accuracy of better than 1m replaced by NAD83(HARN) in the US and PRVI and by NAD83(CSRS) in Canada."
    },
    "transformation": {
        "name": "ATS77 to NAD83 (1)",
        "method": {
            "name": "NTv2",
            "id": {
                "authority": "EPSG",
                "code": 9615
            }
        },
        "parameters": [
            {
                "name": "Latitude and longitude difference file",
                "value": "GS7783.GSB",
                "id": {
                    "authority": "EPSG",
                    "code": 8656
                }
            }
        ],
        "id": {
            "authority": "EPSG",
            "code": 9105
        }
    }
}

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