{"id": "usa-usgs-3dep-1m-seamless", "type": "Collection", "links": [{"rel": "items", "type": "application/geo+json", "href": "https://api.darly.io/collections/usa-usgs-3dep-1m-seamless/items"}, {"rel": "parent", "type": "application/json", "href": "https://api.darly.io/"}, {"rel": "root", "type": "application/json", "href": "https://api.darly.io/"}, {"rel": "self", "type": "application/json", "href": "https://api.darly.io/collections/usa-usgs-3dep-1m-seamless"}], "title": "USA - USGS 3DEP 1m Seamless DEM", "extent": {"spatial": {"bbox": [[-122.12895202636719, 26.44704818725586, -66.78103637695312, 47.5340576171875]]}, "temporal": {"interval": [["1931-01-01T00:00:00+00:00", "2025-04-16T23:59:59+00:00"]]}}, "license": "CC0-1.0", "sci:doi": "10.5066/P13LJKFS", "keywords": ["DEM", "DTM", "elevation", "terrain", "lidar", "3DEP", "USGS", "United States", "1m"], "providers": [{"url": "https://www.usgs.gov/3d-elevation-program", "name": "U.S. Geological Survey, 3D Elevation Program (3DEP)", "roles": ["producer", "licensor", "host"]}, {"url": "https://darly.io", "name": "Darly", "roles": ["processor"]}], "summaries": {"gsd": [1], "instruments": ["lidar"]}, "description": "Seamless 1-meter Digital Elevation Models (S1M) from the USGS 3D Elevation Program (3DEP), distributed via USGS ScienceBase.\n\n**Source & method:** Built from 3DEP-quality airborne **lidar** (Quality Level 2 or better). Individual 3DEP project DEMs are reprocessed into a single continuous bare-earth surface \u2014 seams between projects are removed, water-surface mismatches reduced, and the most recent / highest-quality lidar prioritized per tile. Voids larger than 10 m are backfilled with coarser (1/9 and 1/3 arc-second) DEMs; smaller voids are interpolated. This is a terrain (DTM) product.\n\n**Resolution:** 1 m ground sample distance.\n\n**Coordinate reference:** NAD83(2011) CONUS Albers (EPSG:6350); elevations in meters on NAVD88 (EPSG:5703, GEOID18). Per-item projection details are in each item's assets.\n\n**Coverage:** Production began in 2025 and is ongoing \u2014 tiles publish as they become available, targeting the conterminous US, Hawaii, and Puerto Rico (Alaska excluded). Coverage is incomplete and grows over time.\n\n**Documentation:**\n- [S1M product overview](https://www.usgs.gov/3d-elevation-program/new-product-3d-elevation-program-seamless-1-meter-digital-elevation-model-s1m)\n- [ScienceBase record](https://www.sciencebase.gov/catalog/item/67af83c1d34e5020fb91f170)\n- [USGS 3D Elevation Program](https://www.usgs.gov/3d-elevation-program)\n", "item_assets": {"dtm": {"type": "image/tiff; application=geotiff; profile=cloud-optimized", "roles": ["data", "dtm"], "title": "Digital Terrain Model (DTM)"}, "preview": {"type": "image/jpeg", "roles": ["overview"], "title": "Preview Image"}, "metadata": {"roles": ["metadata"], "title": "ScienceBase Metadata"}, "spatial-metadata": {"type": "application/geopackage+sqlite3", "roles": ["metadata"], "title": "Spatial Metadata (GeoPackage)"}}, "sci:citation": "U.S. Geological Survey, 2025, USGS 3D Elevation Program Seamless 1-Meter Digital Elevation Model (S1M): U.S. Geological Survey data release, https://doi.org/10.5066/P13LJKFS.", "stac_version": "1.0.0", "stac_extensions": ["https://stac-extensions.github.io/item-assets/v1.0.0/schema.json", "https://stac-extensions.github.io/scientific/v1.0.0/schema.json"]}