DEM Document

Purpose

Digital Elevation Model tiles or mosaics for terrain rendering and processing.

GeoJSON (DB metadata)

{
  "type": "Feature",
  "geometry": {"type": "Polygon", "coordinates": [[[
    30.10, 59.90
  ], [
    30.20, 59.90
  ], [
    30.20, 60.00
  ], [
    30.10, 60.00
  ], [
    30.10, 59.90
  ]]]},
  "properties": {
    "type": "DEM",
    "title": "WorldDEM 30m",
    "created_at": "2025-07-01T00:00:00Z",
    "updated_at": "2025-07-01T00:00:00Z",
    "source": {
      "url": "/tiler/tiles/{z}/{x}/{y}@2x",
      "type": "Raster",
      "url_params": {
        "url": "s3://<bucket>/<ResultKey>/<filename>"
      }
    },
    "metadata": {"resolution": 30, "units": "meters", "vertical_datum": "EGM96"}
  }
}

Required properties

properties.type = DEM
Polygon footprint of the tile or mosaic extent
Correct height units and vertical datum in metadata

Publishing workflow

Produce DEM tile or mosaic in GeoTIFF (COG preferred).
Upload to storage and record its URL.
Publish Feature with type DEM referencing raster.

Validation checklist

Nodata value set and overviews present (for COG).
Heights in expected units and datum.
Footprint matches raster extent.

See Common properties for shared fields like legend, metadata, and classification. See also: GeoJSON Strategy and Upload Strategy.