4d203ea1-a5d1-4865-9ea9-78324464ec88_source eng; USA utf8 dataset Simone Montayne 907-451-5020 3354 College Road Fairbanks AK 99709-3707 USA pointOfContact 2023-11-01 ISO 19115 Geographic Information - Metadata ISO 19115:2003/Cor.1:2006(E) Davidof volcano samples and analyses 2023-01-01 publication Alaska Division of Geological & Geophysical Surveys Fairbanks Alaska, United States publisher Loewen, M.W. originator Dietterich, Hannah originator Rosenkrans, H.S. originator https://doi.org/10.14509/31084 CSV Raw Data File RDF 2023-22 4 p Davidof volcano samples and analyses, Raw Data File 2023-22, provides calculations and analytical results from samples collected in the western Aleutian Islands in 2021 by Alaska Volcano Observatory (AVO) geologists Hannah Dietterich and Matt Loewen. The primary target of this sampling was Davidof volcano, a partially submerged 5 km-diameter caldera located in the Rat Islands. Subaerial exposures include Davidof, Khvostof, Lopy, and Pyramid islands. The only prior published work on Davidof volcano was part of the U.S. Geological Survey's post World War II geologic reconnaissance of the Aleutian Islands (Nelson and others, 1959). Nelson and others (1959) only indicate two samples from Davidof volcano that were analyzed petrographically, but prior to this data release no quantitative data for Davidof volcano have been available. This report also includes samples collected during 2021 from the western shore of Little Sitkin Volcano, as well as new electron microprobe analyses from samples previously collected in 2005 and 2015 from Little Sitkin Volcano and 2015 from Segula Volcano. Data associated with this report are archived in the Geologic Database of Information on Volcanoes in Alaska (GeoDIVA; Cameron and others, 2022, doi.org/10.14509/geodiva. This report is released as a Raw Data File with an open end-user license. The data are available from the DGGS website: http://doi.org/10.14509/31084. The only prior published work on Davidof volcano was part of the U.S. Geological Survey's post World War II geologic reconnaissance of the Aleutian Islands (Nelson and others, 1959). Nelson and others (1959) only indicate two samples from Davidof volcano that were analyzed petrographically, but prior to this data release no quantitative data for Davidof volcano have been available. This research describes the nature and character of samples from a past eruption to aid in the discussion of spatial and temporal patterns of Alaska volcanism. In addition, the work supports improvements to eruption scenario forecasts and hazard response. Sampling was done with essential work support by helicopter pilot Mike Grover, as well as the R/V Steadfast crew and AVO field teams during the 2021 western Aleutian Islands analog-to-digital network upgrade. Analytical assistance was provided by Pavel Izbekov (EPMA) and Chris Russo (LA-ICP-MS). Data preparation and metadata review were provided by Cheryl Cameron, Simone Montayne, and editorial handling by Kirsten Janssen. Data review provided by Simone Montayne. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. completed Alaska Division of Geological & Geophysical Surveys GIS Manager 907-451-5020 3354 College Rd Fairbanks AK 99709-3707 USA dggsgis@alaska.gov 8 am to 4:30 pm, Monday through Friday, except State holidays pointOfContact notPlanned Active Volcanoes Age Dates Analyses Analyses and Sampling Analytical Lab Results Analytical Results DGGS Geochemical Data Geochemistry Geochronology Geologic Geologic Hazards Geology Hazards Igneous Igneous Rocks Lab Methods Laser Ablation Major Oxides Microprobe Analysis Petrogenesis Pyroclastics Radiocarbon Ages Radiocarbon Dating Rocks Volcanic Volcanic Ash Volcanic Eruption Volcanic Rocks Volcaniclastic Deposits Volcaniclastics Volcanoes Volcanology theme Alaska Division of Geological & Geophysical Surveys Aleutian Islands Crater Bay Davidof Island Khvostof Island Little Sitkin Island Lopy Island Pyramid Island Rat Islands Segula place Alaska Division of Geological & Geophysical Surveys The State of Alaska makes no express or implied warranties (including warranties of merchantability and fitness) with respect to the character, function, or capabilities of the electronic services 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, any failure thereof, or otherwise, and 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. otherRestrictions Use Constraints: 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. otherRestrictions Access Constraints: This 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). Geologic Database of Information on Volcanoes in Alaska (GeoDIVA) 2022-01-01 publication Alaska Division of Geological & Geophysical Surveys Fairbanks Alaska, United States publisher Cameron, C.E. originator Crass, S.W. originator AVO Staff originator https://doi.org/10.14509/30901 Digital Data Series DDS 20 crossReference Alaska Volcano Observatory geochemical database 2014-01-01 publication Alaska Division of Geological & Geophysical Surveys Fairbanks Alaska, United States publisher Cameron, C.E. originator Snedigar, S.F. originator Nye, C.J. originator https://doi.org/10.14509/29120 Digital Data Series DDS 8 crossReference Geologic Database of Information on Volcanoes in Alaska (GeoDIVA) 2022-01-01 publication Alaska Division of Geological & Geophysical Surveys Fairbanks Alaska, United States publisher Cameron, C.E. originator Crass, S.W. originator AVO Staff originator https://doi.org/10.14509/30901 Digital Data Series DDS 20 crossReference Major-oxide and trace-element geochemical data from rocks collected on Little Sitkin Island, from Little Sitkin Volcano, Alaska 2020-01-01 publication Alaska Division of Geological & Geophysical Surveys Fairbanks Alaska, United States publisher Larsen, J.F. originator Neal, C.A. originator Cameron, C.E. originator https://doi.org/10.14509/30440 Raw Data File RDF 2020-4 4 p crossReference Glass electron microprobe analyses methods, precision and accuracy for tephra studies in Alaska 2023-01-01 publication Alaska Division of Geological & Geophysical Surveys Fairbanks Alaska, United States publisher Loewen, M.W. originator Wallace, K.L. originator Lubbers, Jordan originator Ruth, Dawn originator Izbekov, P.E. originator Larsen, J.F. originator Graham, Nathan originator https://doi.org/10.14509/31045 Miscellaneous Publication MP 174 20 p crossReference vector eng; USA geoscientificInformation 178.161860 179.267000 51.399500 51.998550 2022-01-01 >Carbon: Radiocarbon results for a subset of samples. This table can be linked to the Samples table by the SampleID and at_num columns. >EPMA: Electron microprobe glass analyses. Most analyses are of matrix glass although a few melt inclusion analyses are included, as indicated by a suffix on the at_num and in the sample description. This table can be linked to the Samples table by the SampleID and at_num columns. >GlassAvg: Synthesizes EPMA and Laser analyses as a single row for each sample and uncertainties calculated from repeat sample analyses. This table can be linked to the Samples table by the SampleID and at_num columns. >Laser: Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) analyses of matrix glass. The table also includes the electron microprobe analyses associated with each laser analysis, and thus duplicates some information the EPMA table. This table can be linked to the Samples table by the SampleID and at_num columns. >LaserStandards: Laser ablation secondary standard results. >LaserStandardSummary: Summary statistics for laser ablation secondary standards. Unlike other tables this is not machine-readable and acts as a set of supplementary tables to the text. >Layers: Stratigraphic observations collected at a subset of stations. Station data can be linked with the StationID column. >Samples: Metadata for collected samples. Samples can be linked to the Stations or Layers data through the StationID and layer_name columns. >Stations: Station observations and station coordinates. >WholeRock: Bulk whole rock major and trace element analyses. This table can be linked to the Samples table by the SampleID and at_num columns. true csv unknown State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys 907-451-5020 907-451-5050 3354 College Road Fairbanks AK 99709-3707 USA dggspubs@alaska.gov 8 am to 4:30 pm, Monday through Friday, except State holidays Please view our website (http://www.dggs.alaska.gov) for the latest information on available data. Please contact us using the e-mail address provided above when possible. distributor see http://dx.doi.org/10.14509/31084 Free download http://dx.doi.org/10.14509/31084 csv table information dataset Horizontal Positional Accuracy Report Geologists recorded locations using GPS-enabled iPad mini 5 tablets with the StraboSpot field app. The coordinates have a horizontal error of approximately 10 m. Latitude and longitude are reported in the WGS84 datum. This data releaase is complete. This data releaase is complete. Not applicable This lineage was generated by the FGDC CSDGM to 19139 transformation Field Data - Geologists collected samples during helicopter- and boat-supported fieldwork in May 2021 and recorded locations using GPS-enabled iPad mini 5 tablets in with the StraboSpot field app (Walker and others, 2019; www.strabospot.org/). Latitude and longitude are reported in the WGS84 datum. Station names (StationID) were assigned to sample locations and areas of general observation; sample names (SampleID) correspond to specific samples and include sample descriptions. Laboratory id numbers (at_num) were assigned during laboratory processing and analysis to keep track of "daughter" samples. 2022-01-01T00:00:00 Radiocarbon Analyses - Soil samples were analyzed at the University of Georgia Center for Applied Isotope Studies (CAIS) by Accelerator Mass Spectrometry (AMS) to determine 14C radiocarbon ages. Bulk soil samples were dried at room temperature within 6 weeks of collection in the field. Samples were then submitted to CAIS where humic acid separation and analysis was performed using the following method: root material and other organics were partially removed by sieving through 125 µm nylon mesh. The resulting soil was then treated with 1N hydrochloric acid at 80 ˚C for 1 hour to remove carbonates after which the samples were treated with a solution of 0.5M Na4P2O7 and 0.1M NaOH at room temperature over 24 hours for humic acid extraction. Samples were then precipitated and centrifuged with concentrated hydrochloric acid. Finally, samples were rinsed with Milli_Q water and dried at 105 ˚C overnight. Dried samples were combusted at 900 ˚C in an evacuated sealed quartz ampoule in the presence of CuO. Graphite 14C/13C ratios were measured with a 0.5 MeV accelerator mass spectrometer with isotope ratios compared to Oxalic Acid II (NBS SRM 4990C). Ratios of 13C/12C were measured separately using a stable isotope ratio mass spectrometer and are reported as δ13C relative to Pee Dee Belemnite (PDB). Reported uncalibrated ages (AgeInterpreted) are given in radiocarbon years before 1950 using a 14C half-life of 5568 years. 2022-01-01T00:00:00 Whole Rock Analyses - Bulk lava and tephra samples were crushed to ~1-cm pieces, sonicated, and dried before submittal to the Washington State University Peter Hooper GeoAnalytical Laboratory for X-ray fluorescence (XRF) and solution Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) analysis. Procedures used followed Johnson and others (1999) and technical notes posted at environment.wsu.edu/facilities/geoanalytical-lab/technical-notes/. Detailed analysis and discussion of major and trace element uncertainty for samples submitted by AVO to this lab are provided in Nye and others (2018), which demonstrated 2s precision of less than 0.5 rel.% for major oxides (1.2% for FeOT) and 4 rel.% for most trace elements. 2022-01-01T00:00:00 Electron Microprobe Analyses - Zircon U-Pb sample analysis, Zircon U-Pb data reduction, and Zircon U-PB data interpretation were conducted between 2011 and 2022 and are described in detail in the accompanying report. 2022-01-01T00:00:00 Laser Ablation Analyses - After electron microprobe analysis, a subset of suitably glassy tephras were analyzed by LA-ICP-MS at the Oregon State University W.M. Keck Collaboratory for Plasma Spectrometry using Photo Machines Analyte G2 193 nm ArF Excimer Laser coupled to a Thermo Scientific iCAP-RQ ICP-MS. Ablation was performed at a 30 µm spot at 6.3 J/cm2 beam energy and 7 hz for ~25 seconds. Prior to analysis carbon coat was removed and analysis locations were pre-ablated with four pulses of a 110-µm-diameter beam. Concentrations were determined using in-house reduction software written in Visual Basic and described in Loewen and Kent (2012), using GSE-1G as a calibration standard and using 29Si--as independently constrained by electron microprobe analysis--as an internal standard. Secondary standards included GSD-1G, NIST-612, BHVO-2G, BCR-2G, and ATHO-G. 2022-01-01T00:00:00 otherRestrictions Metadata Use Constraints: If the user has modified this metadata file in any way, the user is obligated to describe the types of modifications the user has made. User specifically agrees not to misrepresent this metadata file, 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. unknown This metadata was automatically generated from the FGDC Content Standard for Digital Geospatial Metadata standard (version FGDC-STD-001-1998) using the 2019-08-12T11:11:00 version of the FGDC CSDGM to ISO 19139 transform. Simone Montayne 907-451-5020 3354 College Road Fairbanks AK 99709-3707 USA pointOfContact