{"action":"create","ckan_id":null,"date_created":"Sat, 28 Mar 2026 21:46:02 GMT","date_finished":null,"harvest_job_id":"c98657db-542f-454b-a49f-06de8f6d4eb3","harvest_source_id":"31f41541-38a0-400b-b240-10ebcb0acd9a","id":"a7f5cf13-da1d-4027-9119-4a9312e4dce8","identifier":"https://dggs.alaska.gov/webpubs/metadata/RDF2023-14.xml","parent_identifier":null,"source_hash":"3611e94890368cf1ed262877690e84362b09e05a35fc2c314325f2a916f9a1bc","source_raw":"Wikstrom Jones, K.M.Wolken, G.J.Daanen, R.P.2023Lidar-derived elevation data for lower Serpentine Glacier and adjacent slopes, Southcentral, Alaska, collected October 14, 2022dataRaw Data FileRDF 2023-14Fairbanks, Alaska, United StatesAlaska Division of Geological & Geophysical Surveys7 p.https://doi.org/10.14509/31012Lidar-derived elevation data for lower Serpentine Glacier and adjacent slopes, Southcentral, Alaska, collected October 14, 2022, Raw Data File 2023-14, uses aerial lidar to produce a classified point cloud, a digital terrain model (DTM), and an intensity model of the unstable slope at Serpentine Glacier, located in Prince William Sound in Southcentral Alaska. Aerial and ground control data were collected on October 14, 2022, and subsequently processed using a suite of geospatial processing software. These data support a paraglacial rock slope destabilization study at Serpentine Glacier and will be used to assess and characterize an ongoing landslide hazard. All files can be downloaded from the Alaska Division of Geological & Geophysical Surveys website (http://doi.org/10.14509/31012).These data support a paraglacial rock slope destabilization study at Serpentine Glacier and will be used to assess and characterize an ongoing landslide hazard.>boundaries: A boundary, also known as an Area of Interest (AOI) or border, that defines the area covered by the data.\t\r\n>classified_points: Classified point cloud data are provided in compressed LAZ format. This dataset only includes ground points and unclassified points; low and high noise points are excluded. Potential vegetation points remain within the unclassified points class. The average nominal pulse spacing is 3.8 cm, and the average nominal point density is 7.9 pts/m2. The average nominal point density for ground points is 5.4 pts/m2. Includes a shapefile index of the spatial location and extent of each point cloud (LAS) bin.\t\r\n>dtm: The DTM represents bare earth elevations, excluding vegetation, bridges, buildings, etc. The DTM is a single-band, 32-bit float GeoTIFF file of 0.20-meter resolution. No Data value is set to -3.40282306074e+38 (32-bit, floating-point minimum).\t\r\n>lidar_intensity: The lidar intensity image depicts the relative amplitude of reflected signals contributing to the point cloud. Lidar intensity is primarily a function of scanned object reflectance in relation to the signal frequency, is dependent on ambient conditions, and is not necessarily consistent between separate scans. The intensity image is a single-band, 32-bit float GeoTIFF file of 1-meter resolution. No Data value is set to -3.40282306074e+38.20221014ground conditioncompleteNone planned-148.354220-148.24619361.14065261.073733ISO 19115 Topic CategorygeoscientificInformationAlaska Division of Geological & Geophysical SurveysAerialAerial GeologyCoastalCoastal and RiverDGGSDebris AvalancheDigital Elevation ModelDigital Terrain ModelElevationEmergency PreparednessEngineeringEngineering GeologyEnvironmentalErosionGeologicGeologic HazardsGeological ProcessGeologyGeomorphologyGeotechnicalGlacialGlacial DepositsGlacial GeologyGlacial GeomorphologyGlacial ProcessesGlaciersHazardsHillshade ImageLandslideLandslide SusceptibilityLiDARLiDAR Intensity ImageLiDAR LAS File FormatPoint Cloud DataRaster ImageRemote SensingRock AvalancheRockfallSlopeSlope InstabilitySurfaceSurficialSurficial GeologyTopographyUnconsolidated DepositsWaterAlaska Division of Geological & Geophysical SurveysHarriman FiordPrince William SoundSerpentine GlacierSouthcentral AlaskaThis report, map, and/or dataset is available directly from the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys (see contact information below).Any hard copies or published datasets utilizing these datasets shall clearly indicate their source. If the user has modified the data in any way, the user is obligated to describe the types of modifications the user has made. The user specifically agrees not to misrepresent these datasets, nor to imply that changes made by the user were approved by the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys. The State of Alaska makes no express or implied warranties (including warranties for merchantability and fitness) with respect to the character, functions, or capabilities of the electronic data or products or their appropriateness for any user's purposes. In no event will the State of Alaska be liable for any incidental, indirect, special, consequential, or other damages suffered by the user or any other person or entity whether from the use of the electronic services or products or any failure thereof or otherwise. In no event will the State of Alaska's liability to the Requestor or anyone else exceed the fee paid for the electronic service or product.Alaska Division of Geological & Geophysical SurveysMetadata Managermailing and physical
3354 College Road
FairbanksAK99709-3707USA(907)451-5020(907)451-5050dggspubs@alaska.gov8 am to 4:30 pm, Monday through Friday, except State holidaysPlease view our website (https://www.dggs.alaska.gov) for the latest information on available data. Please contact us using the e-mail address provided above when possible.These data products were funded by a U.S. Geological Survey Cooperative Agreement G21AC10362-00 and the State of Alaska. We thank Clearwater Air for their aviation expertise and contribution to these data products. The views and conclusions contained in this document are those of the authors and should not be interpreted as necessarily representing the official policies, either expressed or implied, of the U.S. Government.Stevens, D.S.P.Wolken, G.J.Hubbard, T.D.Hendricks, K.A.2018Landslides in AlaskaInformation CircularIC 65Fairbanks, Alaska, United StatesAlaska Division of Geological & Geophysical Surveys2 phttps://doi.org/10.14509/29849Timm, KristinWolken, G.J.2017Deglacierization and the development of glacier-related hazardsInformation CircularIC 63Fairbanks, Alaska, United StatesAlaska Division of Geological & Geophysical Surveys3 phttps://doi.org/10.14509/29752Wolken, G.J.Hendricks, K.A.Daanen, R.P.Overbeck, J.R.Stevens, D.S.P.Masterman, S.S.2017Alaska & climate changeInformation CircularIC 64Fairbanks, Alaska, United StatesAlaska Division of Geological & Geophysical Surveys2 phttps://doi.org/10.14509/29781Not applicableThe data quality is consistent throughout the survey. There was no over-collect except for aircraft turns that were eliminated from the dataset. The data quality is consistent throughout the survey.This data relaease is complete.We did not measure horizontal accuracy for this collection.We measured a mean vertical offset of 44.1 cm between 36 control points and the point cloud (appendix 1, accompanying report). Ten checkpoints were used to determine the non-vegetated vertical accuracy (NVA) of the point cloud ground class using a TIN-based approach. A final accuracy of -0.2 cm was achieved by performing a vertical transformation of the lidar point data. Project NVA was calculated to have a root mean square error (RMSE) of 3.5 cm (appendix 2, accompanying report). We evaluated the relative accuracy for this dataset as the interswath overlap consistency and measured it at 0.9 cm RMSE.Aerial photogrammetric survey - DGGS operates a Riegl VUX1-LR laser scanner integrated with a global navigation satellite system (GNSS) and Northrop Grumman LN-200C inertial measurement unit (IMU). Phoenix LiDAR Systems designed the lidar integration system. The sensor is capable of collecting up to 820,000 points per second at a range of up to 150 m. The scanner operated with a pulse repetition rate of 100,000-400,000 pulses per second at a scan rate between 80 and 160 lines per second. We used a Cessna 180 fixed-wing platform to survey from an elevation of ~100-500 m above ground level, at a ground speed of ~37 m/s, and with a scan angle set from 80 to 280 degrees. The total survey area covers ~24 km2. We flew the aerial survey on October 14, 2022, and covered three separate survey areas (Twentymile River, Barry Arm landslide, and Serpentine Glacier) between take-off and landing. The crew departed the Girdwood Airport at approximately 9:30 am and flew the Serpentine Glacier portion from 11:45 am to 12:45 pm. The Serpentine Glacier area was covered from the delta at sea level up to approximately 1200 m above sea level on each side of the valley, paying special attention to the east-facing slope. The return flight landed back at Girdwood Airport at approximately 1 pm. The weather throughout the survey was overcast with a high ceiling.20221014Ground survey - We collected ground control and checkpoints on October 14, 2022. A Trimble R10-2 GNSS receiver with an internal antenna was deployed at a temporary benchmark on the Serpentine Glacier fan delta (61 degrees 5 minutes 2.9796 seconds N; 148 degrees 18 minutes 6.44 seconds W). Real-time kinematic (RTK) corrections from the base station were applied to points surveyed with a rover Trimble R10-2 GNSS receiver (internal antenna). Forty-six ground control and checkpoints were used for calibration and to assess the vertical accuracy of the point cloud. All points were collected on bare earth.20221014Lidar dataset processing - Point data were processed in SDCimport software for initial filtering and multiple-time-around (MTA) disambiguation. MTA errors, corrected in this process, are the result of ambiguous interpretations of received pulse time intervals and occur more frequently with higher pulse refresh rates. Inertial Measurement Unit (IMU) and Global Navigation Satellite System (GNSS) data were processed in Inertial Explorer, and Spatial Explorer software was used to integrate flightline information with the point cloud. We calibrated the point data at an incrementally precise scale of sensor movement and behavior, incorporating sensor velocity, roll, pitch, and yaw fluctuations throughout the survey. We created macros in Terrasolid software and classified points in accordance with the American Society for Photogrammetry and Remote Sensing (ASPRS) 2019 guidelines (table 1). Once classified, a geometric transformation was applied, and the points were converted from ellipsoidal heights to GEOID12B (Alaska) orthometric heights. ArcGIS Pro was used to derive raster products from the point cloud. The 0.20-meter DTM was interpolated from all ground class returns using a triangulated-irregular network (TIN) method and minimum values. In ArcGIS Pro, we produced a 0.5-meter intensity image by binning and averaging ground and unclassified points, which include vegetation points.2022rasterUniversal Transverse Mercator60.999600-1470500000.0000000coordinate pair.00000001.00000001MetersNAD83 (2011)GRS 806378137298.257222101NAVD88, GEOID12B0.001metersExplicit elevation coordinate included with horizontal coordinatesboundariesA boundary, also known as an Area of Interest (AOI) or border, that defines the area covered by the data.DGGSboundariesclassified_pointsClassified point cloud data are provided in compressed LAZ format. This dataset only includes ground points and unclassified points; low and high noise points are excluded. Potential vegetation points remain within the unclassified points class. The average nominal pulse spacing is 3.8 cm, and the average nominal point density is 7.9 pts/m2. The average nominal point density for ground points is 5.4 pts/m2. Includes a shapefile index of the spatial location and extent of each point cloud (LAS) bin.DGGSclassified_pointsdtmThe DTM represents bare earth elevations, excluding vegetation, bridges, buildings, etc. The DTM is a single-band, 32-bit float GeoTIFF file of 0.20-meter resolution. No Data value is set to -3.40282306074e+38 (32-bit, floating-point minimum).DGGSdtmlidar_intensityThe lidar intensity image depicts the relative amplitude of reflected signals contributing to the point cloud. Lidar intensity is primarily a function of scanned object reflectance in relation to the signal frequency, is dependent on ambient conditions, and is not necessarily consistent between separate scans. The intensity image is a single-band, 32-bit float GeoTIFF file of 1-meter resolution. No Data value is set to -3.40282306074e+38.DGGSlidar_intensityAlaska Division of Geological & Geophysical SurveysMetadata Managermailing and physical
3354 College Road
FairbanksAK99709-3707USA(907)451-5020(907)451-5050dggspubs@alaska.gov8 am to 4:30 pm, Monday through Friday, except State holidaysPlease view our website (https://www.dggs.alaska.gov) for the latest information on available data. Please contact us using the e-mail address provided above when possible.RDF 2023-14The State of Alaska makes no expressed or implied warranties (including warranties for merchantability and fitness) with respect to the character, functions, or capabilities of the electronic data or products or their appropriateness for any user's purposes. In no event will the State of Alaska be liable for any incidental, indirect, special, consequential, or other damages suffered by the user or any other person or entity whether from the use of the electronic services or products or any failure thereof or otherwise. In no event will the State of Alaska's liability to the Requestor or anyone else exceed the fee paid for the electronic service or product.DGGS publications are available as free online downloads or you may purchase paper hard-copies or digital files on CD/DVD or other digital storage media by mail, phone, fax, or email from the DGGS Fairbanks office. To purchase this or other printed reports and maps, contact DGGS by phone (907-451-5020), e-mail (dggspubs@alaska.gov), or fax (907-451-5050). Payment accepted: Cash, check, money order, VISA, or MasterCard. Turnaround time is 1-2 weeks unless special arrangements are made and an express fee is paid. Shipping charge will be the actual cost of postage and will be added to the total amount due. Contact us for the exact shipping amount.Contact DGGS for current pricingdata20230615boundaries, classified points, dtm and lidar intensityhttps://doi.org/10.14509/31012Free download20230615Alaska Division of Geological & Geophysical SurveysSimone MontayneMetadata Managermailing and physical
3354 College Road
FairbanksAK99709-3707USA(907)451-5020(907)451-5050dggspubs@alaska.gov8 am to 4:30 pm, Monday through Friday, except State holidaysFGDC Content Standard for Digital Geospatial MetadataFGDC-STD-001-1998If the user has modified the data in any way they are obligated to describe the types of modifications they have performed in the supporting metadata file. User specifically agrees not to imply that changes they made were approved by the Alaska Department of Natural Resources or Division of Geological & Geophysical Surveys.https://dggs.alaska.gov/metadata/dggs.extdggs metadata extensions","source_transform":null,"status":"error"}