{ "id": "bristlecone-point", "name": "Bristlecone Point", "center": [ -112.1336, 37.62504 ], "width_m": 640, "priority": 2, "source_ids": [ "gnis-north", "usgs-field-guide" ], "question": "How does an isolated ridge divide the surrounding hollows?", "theme": "A ridge between drainages", "view_yaw": -0.95, "view_pitch": 0.67, "locator": { "source_id": "gnis-north", "feature_id": 1439124, "role": "summit represented by two published locators; editorial crop contains both", "accuracy": "Named-feature coordinates, not a surveyed boundary" }, "surface_method": "classified-ground", "schema": 1, "kind": "landscape-study", "checked_at": "2026-10-02", "geometry_status": "Derived from source-classified ground returns; terrain study, not a closed rock scan", "coordinate_system": { "native_horizontal": "NAD83(2011) / UTM 12N (EPSG:6341)", "ept_horizontal": "WGS84 Pseudo-Mercator (EPSG:3857)", "export_horizontal": "WGS84 / UTM 12N (EPSG:32612)", "vertical": "NAVD88, Geoid12B; source heights retained", "units": "metres", "axes": "x east, y up from base_m, z south", "base_m": 2200, "center_utm": [ 399966.6556083468, 4164817.933331676 ], "bounds_utm": [ 399646.6556083468, 4164497.933331676, 400286.6556083468, 4165137.933331676 ], "bounds_wgs84": [ -112.13726959874177, 37.62212136488319, -112.12993068127977, 37.62795852949017 ], "vertical_exaggeration": 1, "transform_note": "EPT projection transformed with pyproj; no claim of survey-grade datum alignment. Centimetre export quantization is not source accuracy." }, "statistics": { "returns_in_crop": 12260086, "density_returns_per_m2": 29.932, "ground_returns": 4260247, "retained_returns": 4260247, "vegetation_candidate_returns": 2753955, "excluded_noise_or_other": 6531, "directly_observed_node_fraction": 0.9462512681964821, "interpolated_node_fraction": 0.04366395738099852, "unsupported_node_fraction": 0.01008477442251937, "isolated_high_cells_repaired": 0, "maximum_nearest_fill_m": 3.0, "cell_m": 1.25, "source_heights_m": [ 2216.5400390625, 2383.820068359375 ], "surface_heights_m": [ 2216.580078125, 2378.60009765625 ], "intensity_display_percentiles": [ 4784.0, 16720.0 ], "vertical_surfaces": "An upper envelope can join returns across a steep face; it cannot recover undercuts, windows, or unseen interiors.", "surface_method": "classified-ground", "editorial_exclusion_node_fraction": 0.0, "unsupported_or_excluded_node_fraction": 0.01008477442251937 }, "levels": [ { "file": "small.glb.gz", "bytes": 426334, "uncompressed_bytes": 1115404, "sha256": "e9f4adb2c5e0fe814a7e3b9801ff0fda7ee380b0f310834cdfd72938b68f8812", "id": "small", "vertices": 16641, "triangles": 31776, "grid_nodes": 129, "spacing_m": 5.0, "degenerate_triangles": 0, "downward_triangles": 0 }, { "file": "balanced.glb.gz", "bytes": 1629308, "uncompressed_bytes": 4451432, "sha256": "3db3ad5558cc6d9cbb33f2e37bf5bc32de787a975e3583c37a0a3d4f83d4a8f6", "id": "balanced", "vertices": 66049, "triangles": 128616, "grid_nodes": 257, "spacing_m": 2.5, "degenerate_triangles": 0, "downward_triangles": 0 }, { "file": "detailed.glb.gz", "bytes": 6382952, "uncompressed_bytes": 17784300, "sha256": "c03a798963c7c6181529a2d3bad67eb24385b7cd4830e6bcc17d06db75c0a76c", "id": "detailed", "vertices": 263169, "triangles": 516914, "grid_nodes": 513, "spacing_m": 1.25, "degenerate_triangles": 0, "downward_triangles": 0 } ], "returns": { "file": "returns.glb.gz", "bytes": 1240138, "uncompressed_bytes": 2881232, "sha256": "dd786736404a05199f9dc811fc6cbe66dd5e8f118782f4cc176a766cc9b01335", "count": 120000, "sampling": "fixed seed 20261002, uniform without replacement from valid crop returns" }, "profiles": "profiles.json.gz", "camera": { "yaw": -0.95, "pitch": 0.67, "distance_m": 1376.0307187330354, "target": [ 0, 130.10009765625, 0 ], "minimum_distance_ratio": 0.85, "useful_range_note": "Landscape inspection only; camera is not permitted to approach a ground-walk distance.", "reference_viewport": [ 1400, 1050 ], "vertical_fov_degrees": 38, "fit_method": "Runtime projects actual active vertices to fit the viewport with a 14 percent frame margin; distance_m records the poster reference view.", "closest_reviewed_distance_ratio": 0.85 }, "bounds_local": [ [ -320.0, 16.580078125, -320.0 ], [ 320.0, 178.60009765625, 320.0 ] ], "source_dataset": { "id": "USGS_LPC_UT_Southern_QL1_2018_LAS_2019", "acquired": "2018-04-27 / 2018-07-29 project interval", "published": "2019-06-03", "url": "https://registry.opendata.aws/usgs-lidar/", "license": "US Government Public Domain", "credit": "Map services and data available from U.S. Geological Survey, National Geospatial Program." }, "processing": { "mesh": "Source class 2 ground only. Highest retained return per nearest grid node; nearest interpolation up to 3 m; isolated spikes exceeding all 8 neighbors by 6 m lowered to neighbor maximum. No morphological closing.", "vegetation": "Source classes 3/4/5 plus low-intensity multiple echoes and low-intensity raised returns over nearby gentle classified ground are excluded. This is an imperfect heuristic, not a species/rock classifier.", "lighting": "Normals and static 12-direction terrain occlusion are derived; material color, studio lighting and display category colors are illustrative.", "detail": "Three nested node grids; no-data cells omitted at every LOD; low LOD can omit extra edge triangles to preserve holes.", "exclusions": "Elliptical uncertainty masks remove the entire plan footprint around unresolved arch/alcove geometry; all LODs conservatively preserve these holes. They are not measured opening outlines." }, "limitations": [ "Hidden rock surfaces, undercuts and windows are not reconstructed.", "A vertical face is an interpolated connection between top-surface samples, not a wall scan.", "Vegetation filtering can leave crowns or remove dark rock; inspect the return view.", "NAIP is overhead imagery from a different year; it cannot supply photographic detail on vertical faces.", "The cut boundary is an editorial crop; there is no modeled geology beneath it.", "No route, current condition, erosion rate or collapse forecast is inferred." ], "posters": { "large": "poster.webp", "small": "poster-small.webp" }, "quality_status": "accepted_local_educational_landscape", "exclusions": [], "source_acquisition": { "path": "acquisition.json", "points_sha256": "791d08678e35be7039097dcd8ab14501d8f3b4dc6d2795a2519baf9fb2728ff7", "source_object_count": 388 }, "editorial": { "lede": "A separate ridge rises between the surrounding hollows.", "body": "USGS identifies Bristlecone Point east of the main amphitheater. Two published summit locators fall within this crop. The exhibit follows the ridge’s topographic form, complementing Boat Mesa’s broader upper surface without implying that a place name identifies the trees visible today.", "lesson": "Move the section from north to south and compare the ridge width and neighboring lows. The surface uses the survey’s ground class; the full return view includes vegetation. Display categories do not identify species.", "limit": "This is Bristlecone Point, not Bristlecone Loop near Rainbow Point. The ground class may omit standing rock; no tree species, tree age, trail or rock contact is inferred.", "caption": "The isolated Bristlecone Point landscape study, distinct from the southern Bristlecone Loop.", "evidence_title": "A ridge rather than a route", "evidence_note": "Sections measure modern surface form. They do not establish a walkable line, vegetation species or the underlying stratigraphy.", "annotation_title": "Bristlecone Point name locators", "annotation_text": "The USGS summit record has two points about 145 m apart. Both lie in this crop; the label marks their midpoint, not a surveyed boundary." }, "imagery": { "publisher": "USDA Farm Service Agency / FPAC", "dataset": "National Agriculture Imagery Program (NAIP), Utah 2024", "retrieved_at": "2026-10-02T09:37:58.070411+00:00", "source_pixels_m": 0.6, "export_pixels": 1067, "export_pixel_m": 0.5998125585754451, "crs": "EPSG:32612", "requested_bounds": [ 399646.6556083468, 4164497.933331676, 400286.6556083468, 4165137.933331676 ], "export_extent": { "xmin": 399646.6556083468, "ymin": 4164497.933331676, "xmax": 400286.6556083468, "ymax": 4165137.933331676, "spatialReference": { "wkid": 32612, "latestWkid": 32612 } }, "flight_dates": [ "2024-07-23" ], "images": [ { "OBJECTID": 195950, "Name": "m_3711231_ne_12_060_20240723", "Category": 1, "year_ts": 2024, "ST": "UT", "QQNAME": "3711231NE060", "QQDATE": 1721692800000, "iDate_ts": 1749744257170 }, { "OBJECTID": 195984, "Name": "m_3711223_se_12_060_20240723", "Category": 1, "year_ts": 2024, "ST": "UT", "QQNAME": "3711223SE060", "QQDATE": 1721692800000, "iDate_ts": 1749744257170 } ], "catalog_url": "https://apps.geo.fpac.usda.gov/geo-imagery/rest/services/naip/conus_naip/ImageServer/query?f=json&geometry=%7B%22xmin%22%3A399646.6556083468%2C%22ymin%22%3A4164497.933331676%2C%22xmax%22%3A400286.6556083468%2C%22ymax%22%3A4165137.933331676%2C%22spatialReference%22%3A%7B%22wkid%22%3A32612%7D%7D&geometryType=esriGeometryEnvelope&inSR=32612&spatialRel=esriSpatialRelIntersects&outFields=%2A&returnGeometry=false&where=Category%3D1+AND+year_ts%3D2024", "export_url": "https://apps.geo.fpac.usda.gov/geo-imagery/rest/services/naip/conus_naip/ImageServer/exportImage?f=json&bbox=399646.6556083468%2C4164497.933331676%2C400286.6556083468%2C4165137.933331676&bboxSR=32612&imageSR=32612&size=1067%2C1067&format=png&pixelType=U8&interpolation=RSP_BilinearInterpolation&adjustAspectRatio=false&bandIds=0%2C1%2C2&mosaicRule=%7B%22mosaicMethod%22%3A%22esriMosaicLockRaster%22%2C%22lockRasterIds%22%3A%5B195950%2C195984%5D%2C%22mosaicOperation%22%3A%22MT_FIRST%22%7D", "direct_image_url": "https://apps.geo.fpac.usda.gov/geo-imagery/rest/services/naip/conus_naip/ImageServer/exportImage?f=image&bbox=399646.6556083468%2C4164497.933331676%2C400286.6556083468%2C4165137.933331676&bboxSR=32612&imageSR=32612&size=1067%2C1067&format=png&pixelType=U8&interpolation=RSP_BilinearInterpolation&adjustAspectRatio=false&bandIds=0%2C1%2C2&mosaicRule=%7B%22mosaicMethod%22%3A%22esriMosaicLockRaster%22%2C%22lockRasterIds%22%3A%5B195950%2C195984%5D%2C%22mosaicOperation%22%3A%22MT_FIRST%22%7D", "original_sha256": "56d3308fbf1af6c6e82519d802bb77b3eabb72e7bcc8ed44f684230a16d77748", "license": "US Government Public Domain", "license_url": "https://catalog.data.gov/dataset/national-agriculture-imagery-program-naip-imagery", "processing": "Locked 2024 primary rasters, RGB bands 0/1/2, orthographic drape; bilinear export, WebP encoding. No invented detail.", "limitations": "Leaf-on aerial imagery from a different year than the 2018 topography; acquisition shadows, tree crowns and metre-scale registration error remain. Displayed only in the overhead evidence view, never as a wall photograph." }, "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": "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" } ], "annotations": [ { "title": "Bristlecone Point name locators", "text": "The USGS summit record has two points about 145 m apart. Both lie in this crop; the label marks their midpoint, not a surveyed boundary.", "position": [ 0.0, 166.909912109375, 0.0 ], "anchor_surface_elevation_navd88_m": 2361.909912109375, "display_lift_m": 5, "coordinate_source": { "source_id": "gnis-north", "feature_id": 1439124, "role": "summit represented by two published locators; editorial crop contains both", "accuracy": "Named-feature coordinates, not a surveyed boundary" }, "height_method": "Nearest fine-grid sample at published locator; display lift is illustrative; no surveyed feature elevation asserted" } ], "static_profile": { "row": 64, "direction": "west to east", "north_offset_m": 0, "minimum_m": 2269.7, "maximum_m": 2371.21, "vertical_exaggeration": 1, "source": "profiles.json.gz" }, "source_coordinate_check": "source-coordinate-check.json", "textures": [ { "file": "aerial.webp", "bytes": 334504, "sha256": "901604818a25ac61739d5ae862fdbae2406bf1a6023da30922b6cf58cb1b90bf", "role": "separate overhead evidence image, never wall texture" }, { "file": "aerial-small.webp", "bytes": 93752, "sha256": "c71de881d071ce8c7623596e42155c05cb2dea9c89f25538fd164657acdcd4bb", "role": "separate overhead evidence image, never wall texture" } ], "quality_record": "quality.json" }