{
  "schema": 1,
  "retrieved_at": "2026-10-02",
  "sources": [
    {
      "id": "gnis-north",
      "title": "USGS geographic names: northern Bryce landforms",
      "publisher": "US Geological Survey / National Geospatial Program",
      "url": "https://carto.nationalmap.gov/arcgis/rest/services/geonames/MapServer/5",
      "date": null,
      "rights": "US Government Public Domain",
      "supports": "Official names and published locators for Boat Mesa, Sinking Ship, Chinese Wall, Bristlecone Point and audited alternatives. Name points are not surveyed feature boundaries.",
      "evidence": "gnis-north-landforms.json"
    },
    {
      "id": "nps-fairyland",
      "title": "Fairyland Point",
      "publisher": "National Park Service",
      "url": "https://www.nps.gov/places/000/fairyland-point.htm",
      "date": "2024-10-10",
      "rights": "Paraphrased government text; page photographs not copied",
      "supports": "Boat Mesa conglomerate cap, Sinking Ship fault interpretation, Fairyland and Campbell Canyon context. No numeric erosion age/rate derived here.",
      "evidence": "nps-fairyland.html"
    },
    {
      "id": "nps-tower",
      "title": "Tower Bridge",
      "publisher": "National Park Service",
      "url": "https://www.nps.gov/thingstodo/tower-bridge.htm",
      "date": "2024-10-10",
      "rights": "Paraphrased government text; no photograph copied",
      "supports": "Official identity and relation to southern Fairyland Loop; not a ground-scan record.",
      "evidence": "nps-tower.html"
    },
    {
      "id": "nps-mossy",
      "title": "Mossy Cave / Water Canyon",
      "publisher": "National Park Service",
      "url": "https://www.nps.gov/places/000/mossy-cave.htm",
      "date": "2024-10-10",
      "rights": "Paraphrased government text; no photograph copied",
      "supports": "Water Canyon identity, Tropic Ditch completion in 1892 and irrigation context. Historical description does not establish current flow.",
      "evidence": "nps-mossy.html"
    },
    {
      "id": "nps-mossy-wayside",
      "title": "Mossy Cave wayside",
      "publisher": "National Park Service",
      "url": "https://www.nps.gov/places/mossy-cave-wayside.htm",
      "date": "2024-10-10",
      "rights": "Paraphrased government text; no photograph copied",
      "supports": "Alcove formation by seeping water and protection request to remain outside.",
      "evidence": "nps-mossy-wayside.html"
    },
    {
      "id": "nps-pois",
      "title": "NPS public points of interest",
      "publisher": "NPS National Geospatial Program",
      "url": "https://mapservices.nps.gov/arcgis/rest/services/NationalDatasets/NPS_Public_POIs/FeatureServer/0",
      "date": null,
      "rights": "Unrestricted public government mapping; source methods retained; no claim to original US Government works",
      "supports": "Distinct waterfall, cave, viewpoint and trailhead roles. Waterfall 1994 and cave 5289 agree closely with independently mapped OSM positions. Tower viewpoint 4362 is distinct from the rock locator.",
      "evidence": "nps-public-locators.json"
    },
    {
      "id": "osm-locators",
      "title": "Tower Bridge and Mossy Cave named locators",
      "publisher": "OpenStreetMap contributors",
      "url": "https://www.openstreetmap.org/copyright",
      "date": "2026-10-02",
      "rights": "ODbL 1.0; copyright OpenStreetMap contributors",
      "supports": "Tower Bridge node 391696698; comparison points for Mossy Cave and Tropic Ditch Falls. These do not replace NPS arrival points.",
      "evidence": "osm-target-locators.json"
    },
    {
      "id": "nps-china-archive",
      "title": "China Wall from Fairyland Loop: archival photograph",
      "publisher": "Bryce Canyon National Park Museum and Archives",
      "author": "Maurice Cope",
      "url": "https://npgallery.nps.gov/AssetDetail/855691eb110f4d85aa4e4e0c8671f28d",
      "date": null,
      "rights": "Public domain; mandatory credit: Courtesy Bryce Canyon National Park, Photographer Maurice Cope, Museum Catalog Number BRCA 532/001-#191",
      "supports": "Independent oblique reference and NPS name China Wall. Capture date and camera calibration are not established; not used for mesh geometry, texture or change-rate measurement.",
      "evidence": "nps-china-archive.html"
    },
    {
      "id": "usgs-geology",
      "title": "Geologic map of Bryce Canyon National Park and vicinity: explanatory report",
      "publisher": "US Geological Survey",
      "author": "W. E. Bowers",
      "url": "https://pubs.usgs.gov/imap/2108/report.pdf",
      "date": "1990",
      "rights": "US Government Public Domain",
      "supports": "Thin divides, ridges and hoodoos between eroding gullies; named Chinese Wall and Tower Bridge. Historical numerical erosion estimates are not used in this product."
    },
    {
      "id": "usgs-field-guide",
      "title": "The geology of the Grand Staircase in southern Utah: a road log and guide for public school teachers",
      "publisher": "USGS-hosted GSA 2002 Rocky Mountain Section field guide",
      "author": "Larry E. Davis and Robert L. Eves",
      "url": "https://pubs.usgs.gov/of/2002/0172/pdf/chap6.pdf",
      "date": "2002",
      "rights": "Reference only; no third-party chapter map or photograph reproduced. Hosting on a government domain is not used as a copyright determination.",
      "supports": "Regional map identity for Bristlecone Point and northern landmarks; no modern route or operational status inferred.",
      "evidence": "usgs-field-guide.pdf"
    },
    {
      "id": "usgs-lidar",
      "title": "USGS 3DEP lidar, UT Southern QL1 2018",
      "publisher": "USGS; public EPT organization by Hobu",
      "url": "https://registry.opendata.aws/usgs-lidar/",
      "date": "2018 acquisition / 2019 publication",
      "rights": "US Government Public Domain",
      "supports": "Independent measured airborne returns; per-model acquisition record retains every source object URL and hash.",
      "evidence": "usgs-lidar-rights.html"
    },
    {
      "id": "usda-naip",
      "title": "National Agriculture Imagery Program imagery",
      "publisher": "USDA FPAC / Farm Service Agency",
      "url": "https://catalog.data.gov/dataset/national-agriculture-imagery-program-naip-imagery",
      "date": "2025-07-09 dataset record; per-crop 2024 flight dates retained separately",
      "rights": "US Government Public Domain, dataset-specific public-domain label",
      "supports": "Rights and orthorectified aerial imagery; used only in north-up evidence views, never wall photographs."
    },
    {
      "id": "utah-naip",
      "title": "Utah NAIP specifications",
      "publisher": "Utah Geospatial Resource Center",
      "url": "https://gis.utah.gov/products/sgid/aerial-photography/naip/",
      "date": null,
      "rights": "Reference only",
      "supports": "Utah 2024 NAIP at 0.6 m source resolution; +/-4 m stated horizontal accuracy. Export sampling is not a new accuracy claim.",
      "evidence": "utah-naip.html"
    },
    {
      "id": "opentopography",
      "title": "OpenTopography public dataset catalog",
      "publisher": "OpenTopography",
      "url": "https://portal.opentopography.org/csw/catalog.json",
      "date": "2026-10-02 audit",
      "rights": "Metadata review only; no scan copied",
      "supports": "804 records searched. The one Bryce keyword match is a 2016 airborne Straight Cliffs survey east of these targets, not a north-landmark ground scan.",
      "evidence": "scan-catalog-audit.json"
    }
  ],
  "credits": [
    "Map services and data available from U.S. Geological Survey, National Geospatial Program.",
    "Aerial imagery: USDA Farm Service Agency / FPAC, National Agriculture Imagery Program, 2024.",
    "Tower Bridge locator: © OpenStreetMap contributors, ODbL 1.0. NPS mapped locators are separately identified.",
    "Three.js 0.186.1 under the MIT license; existing Gelasio and Inter fonts under SIL OFL. All licenses remain local."
  ],
  "conflicts": [
    "China Wall is the NPS archival name; USGS GNIS uses Chinese Wall.",
    "NPS Tower Bridge viewpoint, NPS trailhead, OSM rock point and historical mapped rock position have different coordinate roles; the context crop and conservative exclusion retain the distinction.",
    "The NPS Tower Bridge wayside pairs 3.0 miles with 2.4 km, an inconsistent conversion; this product does not repeat it or offer route metrics.",
    "OpenTopography’s Straight Cliffs page mentions terrestrial digital outcrop work, but the downloadable collection is explicitly airborne and its footprint is east of Bryce.",
    "Bowers I-2108 is cited as 1990 in the NPS ancillary report and USGS bibliographies; some USGS/Utah catalog entries use 1991. The 1990 report date is retained here."
  ],
  "scope": "Historical educational landscape derivatives. No ground scan, surveyed hidden surface, current condition, public release or agency endorsement."
}