EPSG:4494

PROJCS["CGCS2000 / Gauss-Kruger zone 16",
    GEOGCS["China Geodetic Coordinate System 2000",
        DATUM["China_2000",
            SPHEROID["CGCS2000",6378137,298.257222101,
                AUTHORITY["EPSG","1024"]],
            AUTHORITY["EPSG","1043"]],
        PRIMEM["Greenwich",0,
            AUTHORITY["EPSG","8901"]],
        UNIT["degree",0.0174532925199433,
            AUTHORITY["EPSG","9122"]],
        AUTHORITY["EPSG","4490"]],
    PROJECTION["Transverse_Mercator"],
    PARAMETER["latitude_of_origin",0],
    PARAMETER["central_meridian",93],
    PARAMETER["scale_factor",1],
    PARAMETER["false_easting",16500000],
    PARAMETER["false_northing",0],
    UNIT["metre",1,
        AUTHORITY["EPSG","9001"]],
    AUTHORITY["EPSG","4494"]]

PROJCRS["CGCS2000 / Gauss-Kruger zone 16",
    BASEGEOGCRS["China Geodetic Coordinate System 2000",
        DATUM["China 2000",
            ELLIPSOID["CGCS2000",6378137,298.257222101,
                LENGTHUNIT["metre",1]]],
        PRIMEM["Greenwich",0,
            ANGLEUNIT["degree",0.0174532925199433]],
        ID["EPSG",4490]],
    CONVERSION["6-degree Gauss-Kruger zone 16",
        METHOD["Transverse Mercator",
            ID["EPSG",9807]],
        PARAMETER["Latitude of natural origin",0,
            ANGLEUNIT["degree",0.0174532925199433],
            ID["EPSG",8801]],
        PARAMETER["Longitude of natural origin",93,
            ANGLEUNIT["degree",0.0174532925199433],
            ID["EPSG",8802]],
        PARAMETER["Scale factor at natural origin",1,
            SCALEUNIT["unity",1],
            ID["EPSG",8805]],
        PARAMETER["False easting",16500000,
            LENGTHUNIT["metre",1],
            ID["EPSG",8806]],
        PARAMETER["False northing",0,
            LENGTHUNIT["metre",1],
            ID["EPSG",8807]]],
    CS[Cartesian,2],
        AXIS["northing (X)",north,
            ORDER[1],
            LENGTHUNIT["metre",1]],
        AXIS["easting (Y)",east,
            ORDER[2],
            LENGTHUNIT["metre",1]],
    USAGE[
        SCOPE["Topographic mapping (medium scale)."],
        AREA["China - between 90°E and 96°E."],
        BBOX[27.71,90,47.9,96.01]],
    ID["EPSG",4494]]

PROJCS["CGCS2000_GK_Zone_16",
    GEOGCS["GCS_China_Geodetic_Coordinate_System_2000",
        DATUM["D_China_2000",
            SPHEROID["CGCS2000",6378137.0,298.257222101]],
        PRIMEM["Greenwich",0.0],
        UNIT["Degree",0.0174532925199433]],
    PROJECTION["Gauss_Kruger"],
    PARAMETER["False_Easting",16500000.0],
    PARAMETER["False_Northing",0.0],
    PARAMETER["Central_Meridian",93.0],
    PARAMETER["Scale_Factor",1.0],
    PARAMETER["Latitude_Of_Origin",0.0],
    UNIT["Meter",1.0]]

proj4.defs("EPSG:4494","+proj=tmerc +lat_0=0 +lon_0=93 +k=1 +x_0=16500000 +y_0=0 +ellps=GRS80 +units=m +no_defs +type=crs");

{
    "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json",
    "type": "ProjectedCRS",
    "name": "CGCS2000 / Gauss-Kruger zone 16",
    "base_crs": {
        "name": "China Geodetic Coordinate System 2000",
        "datum": {
            "type": "GeodeticReferenceFrame",
            "name": "China 2000",
            "ellipsoid": {
                "name": "CGCS2000",
                "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": 4490
        }
    },
    "conversion": {
        "name": "6-degree Gauss-Kruger zone 16",
        "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": 93,
                "unit": "degree",
                "id": {
                    "authority": "EPSG",
                    "code": 8802
                }
            },
            {
                "name": "Scale factor at natural origin",
                "value": 1,
                "unit": "unity",
                "id": {
                    "authority": "EPSG",
                    "code": 8805
                }
            },
            {
                "name": "False easting",
                "value": 16500000,
                "unit": "metre",
                "id": {
                    "authority": "EPSG",
                    "code": 8806
                }
            },
            {
                "name": "False northing",
                "value": 0,
                "unit": "metre",
                "id": {
                    "authority": "EPSG",
                    "code": 8807
                }
            }
        ]
    },
    "coordinate_system": {
        "subtype": "Cartesian",
        "axis": [
            {
                "name": "Northing",
                "abbreviation": "X",
                "direction": "north",
                "unit": "metre"
            },
            {
                "name": "Easting",
                "abbreviation": "Y",
                "direction": "east",
                "unit": "metre"
            }
        ]
    },
    "scope": "Topographic mapping (medium scale).",
    "area": "China - between 90°E and 96°E.",
    "bbox": {
        "south_latitude": 27.71,
        "west_longitude": 90,
        "north_latitude": 47.9,
        "east_longitude": 96.01
    },
    "id": {
        "authority": "EPSG",
        "code": 4494
    }
}

<?xml version="1.0" encoding="utf-8"?>
<Map srs="+proj=tmerc +lat_0=0 +lon_0=93 +k=1 +x_0=16500000 +y_0=0 +ellps=GRS80 +units=m +no_defs +type=crs">
	<Layer srs="+proj=tmerc +lat_0=0 +lon_0=93 +k=1 +x_0=16500000 +y_0=0 +ellps=GRS80 +units=m +no_defs +type=crs">
	</Layer>
</Map>

INSERT into spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext) values ( 4494, 'EPSG', 4494, '+proj=tmerc +lat_0=0 +lon_0=93 +k=1 +x_0=16500000 +y_0=0 +ellps=GRS80 +units=m +no_defs +type=crs', 'PROJCS["CGCS2000 / Gauss-Kruger zone 16",GEOGCS["China Geodetic Coordinate System 2000",DATUM["China_2000",SPHEROID["CGCS2000",6378137,298.257222101,AUTHORITY["EPSG","1024"]],AUTHORITY["EPSG","1043"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4490"]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin",0],PARAMETER["central_meridian",93],PARAMETER["scale_factor",1],PARAMETER["false_easting",16500000],PARAMETER["false_northing",0],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AUTHORITY["EPSG","4494"]]');