{"action":"create","ckan_id":null,"date_created":"Sat, 14 Feb 2026 20:53:17 GMT","date_finished":null,"harvest_job_id":"b099ff79-e0c0-4989-8abd-bd643fba622f","harvest_source_id":"31f41541-38a0-400b-b240-10ebcb0acd9a","id":"8e266489-f20a-4833-a5cd-88c45f8e5cd6","identifier":"https://dggs.alaska.gov/webpubs/metadata/RDF2025-15.xml","parent_identifier":null,"source_hash":"146e7f4f05b791c230e68813d5af864d25d6cc1bb5f105f0e59cbe89d41a4d8c","source_raw":"Loewen, M.W.Dietterich, H.R.Lubbers, JordanVan Eaton, A.R.2025Tephra samples and analyses from the 2018-2023 eruption of Semisopochnoi Volcano, AlaskaspreadsheetRaw Data FileRDF 2025-15Fairbanks, Alaska, United StatesAlaska Division of Geological & Geophysical Surveys13 p.https://doi.org/10.14509/31645Tephra samples and analyses from the 2018-2023 eruption of Semisopochnoi Volcano, Alaska, Raw Data File 2025-15, includes samples and analyses collected from the 2018-2023 eruption of Semisopochnoi volcano in the western Aleutian Islands, Alaska. Samples were collected during two field visits: May 30 to June 1, 2021, and June 10, 2023. A total of sixteen samples were collected across Semisopochnoi Island at varying distances from the eruption source, the north crater of Mount Young. Samples were collected from the surface on snow, grass, or other substrates that suggested deposition during recent eruptive activity but are, in all cases, aggregates of prior eruption events up to the sample date and may contain minor wind-blown contamination from older surfaces. These data and report are available from the DGGS website: http://doi.org/10.14509/31645 and a subset of the results are archived in the Geologic Database of Information on Volcanoes in Alaska (GeoDIVA; Cameron and others, 2022, doi.org/10.14509/geodiva).These data describe the nature of samples from a past eruption to aid in discussing Alaska volcanism's spatial and temporal patterns. In addition, the work supports improvements to eruption scenario forecasts and hazard response.>data: Analytical lab data and accompanying data dictionary20212025ground conditionCompleteNone planned179.492357179.72981952.00118851.917959ISO 19115 Topic CategorygeoscientificInformationAlaska Division of Geological & Geophysical SurveysActive VolcanoesAeolianAleutian ArcAnalysesAnalyses and SamplingAnalytical Lab ResultsAnalytical ResultsAshfallChemistryCoastalCoastal and RiverDGGSGeochemical DataGeochemistryGeologicGeologic HazardsGeological ProcessGeologyGrain SizeHazardsIgneousLab MethodsMagmatic ArcMajor OxidesMethodsMicroprobe AnalysisMinor OxidesPyroclastic FallPyroclasticsSample LocationSurfaceTephraVolcanicVolcanic ArcVolcanic AshVolcanic EruptionVolcaniclastic DepositsVolcaniclasticsVolcanoesVolcanologyAlaska Division of Geological & Geophysical SurveysAleutian IslandsSemisopochnoiSemisopochnoi IslandThis 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.Field sampling in 2021 and 2023 was conducted in association with Alaska Volcano Observatory geophysical monitoring network maintenance, with logistical support from field engineers on the joint mission. The 2021 work was supported by the crew of the R/V Steadfast and helicopter pilot Mike Grover. The 2023 work was supported by the crew of the R/V Tiglax. Simone Montayne provided metadata review. Kristi Wallace, Cheryl Cameron, and Scott Crass provided data and subject matter metadata review. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.Cameron, C.E.Crass, S.W.AVO Staff2022Geologic Database of Information on Volcanoes in Alaska (GeoDIVA)Digital Data SeriesDDS 20Fairbanks, Alaska, United StatesAlaska Division of Geological & Geophysical Surveyshttps://doi.org/10.14509/30901Loewen, M.W.Wallace, K.L.Lubbers, JordanRuth, DawnIzbekov, P.E.Larsen, J.F.Graham, Nathan2023Glass electron microprobe analyses methods, precision and accuracy for tephra studies in AlaskaMiscellaneous PublicationMP 174Fairbanks, Alaska, United StatesAlaska Division of Geological & Geophysical Surveys20 phttps://doi.org/10.14509/31045The accompanying report and data tables provide a comprehensive discussion of processing methods, with errors reported in the tables where applicable. This data is being released as part of the DGGS RDF series, which includes content describing approved techniques and methods for the collection, storage, visualization, analysis, and interpretation of scientific data. While the information has been reviewed by several geologists familiar with the study area, the data and report have not undergone formal review for technical content or conformity to DGGS editorial standards. For inquiries regarding analytical values or procedures, the originating lab is the best point of contact.Not applicableThis data release is complete.Sample location coordinates were obtained using recreational-grade GPS units, with a typical reported accuracy of about 10 meters.Sample collection - Samples were collected in 2021 and 2023. Locations were recorded using tablet-integrated GPS with an accuracy of approximately 10 meters. In early summer 2021, ash deposits forming a distinct layer atop clean snow from winter 2020 through spring 2021 were sampled at three field sites. Two sites (21SMHD19 and 21SMHD07) were sampled within 30 x 30 cm squares, and one site (21SMHD12B) within a 20 x 20 cm square. Ash and snow were placed in gallon-sized sealable plastic bags, gravity-filtered using Whatman 541 filter paper, and dried at 40-50 degrees C for over 24 hours prior to weighing. Station identifiers (StationID) were assigned to sample locations and general observation sites. Sample identifiers (SampleID) refer to individual samples and include descriptive details. Laboratory identification numbers (at_num) were assigned during processing and analysis.2024Analytical methods - Grain size distributions for nine bulk samples were assessed using three techniques: standard sieving, laser diffraction particle size analysis, and dynamic image analysis. Tephra samples were embedded in epoxy and polished for electron probe microanalysis (EPMA) at the Alaska Tephra Laboratory. EPMA was conducted at the University of Alaska Fairbanks Advanced Instrumentation Laboratory using a JEOL JXA 8530F electron microprobe. For each sample, polished epoxy mounts were prepared for three particle size fractions: 63-125 micrometer, 125-250 micrometer, and 250-500 micrometer. These fractions were qualitatively examined using a JEOL 6510LV scanning electron microscope at the Alaska Tephra Laboratory.2025point0.00000010.0000001decimal degreesWGS84WGS 846378137298.257223563rdf2025_015_data.xlsx, rdf2025_015_data_dictionary.xlsxAnalytical lab data and accompanying data dictionaryDGGSdataAlaska 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 2025-15The 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 pricingspreadsheet20250801tablehttps://doi.org/10.14509/31645Free download20250801Alaska 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"}