George R. Snyder Alicia F. Balster-Gee Daniel S. Brothers Drake M. Singleton Jason S. Padgett Jenna C. Hill Andrew C. Ritchie SeanPaul M. La Selle Jared W. Kluesner Brian Sherrod Daniel C. Powers Peter Dal Ferro Jackson E. Currie 20240615 comma-delimited text data release DOI:10.5066/P9W5RAL4 Pacific Coastal and Marine Science Center, Santa Cruz, California U.S. Geological Survey https://doi.org/10.5066/P9W5RAL4 George R. Snyder Alicia F. Balster-Gee Daniel S. Brothers Drake M. Singleton Jason S. Padgett Jenna C. Hill Andrew C. Ritchie SeanPaul M. La Selle Jared W. Kluesner Brian Sherrod Daniel C. Powers Peter Dal Ferro Jackson E. Currie 2024 data release DOI:10.5066/P9W5RAL4 Pacific Coastal and Marine Science Center, Santa Cruz, CA U.S. Geological Survey Suggested Citation: Snyder, G.R., Balster-Gee, A.F., Brothers, D.S., Singleton, D.M., Padgett, J.S., Hill, J.C., Ritchie, A.C., La Selle, S.M., Kluesner, J.W., Sherrod, B., Powers, D.C., Dal Ferro, P., and Currie, J.E., 2024, Seismic sub-bottom, sediment core, and radiocarbon data collected in Ozette Lake, Washington: U.S. Geological Survey data release, https://doi.org/10.5066/P9W5RAL4. https://doi.org/10.5066/P9W5RAL4 Seismic reflection data and cores were collected in Ozette Lake, Washington, in 2019. Radiocarbon samples were taken from cores in select locations. These data were used to investigate submarine landslide deposits triggered by large Cascadia Subduction Zone earthquakes. Identification of fault-related submarine hazards is a primary mission of the USGS Coastal and Marine Geology Program. In the US Pacific Northwest region, the greatest earthquake and tsunami threat is posed by the Cascadia Subduction Zone. From 2019-2021 the USGS carried out a detailed field investigation of earthquake-triggered landslide deposits in Ozette Lake, WA, to reconstruct the timing and severity of large subduction zone earthquakes in northern Cascadia. Field data collected as part of this investigation include boomer single-channel seismic reflection profiles, chirp seismic reflection profiles, and sediment cores. These data are intended to further our understanding of geologic hazards relating to the Cascadia Subduction Zone, improve risk assessments for local communities and critical infrastructure, and to provide data for future research on regional tectonic and sedimentary history of northern Cascadia. Additional information about the field activities from which these data were derived is available online at: https://cmgds.marine.usgs.gov/fan_info.php?fan=2019-622-FA https://cmgds.marine.usgs.gov/fan_info.php?fan=2021-641-FA Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. 20191018 20191024 Ground conditions at time data were collected Complete None planned -124.66785 -124.607701 48.15099 48.05184 USGS Metadata Identifier USGS:f18b36ed-1c2a-4307-bbb2-873a1c0a27cc ISO 19115 Topic Category inlandWaters geoscientificInformation location Data Categories for Marine Planning substrate USGS Thesaurus geochemistry core analysis geospatial datasets Marine Realms Information Bank (MRIB) keywords data processing sediment None U.S. Geological Survey USGS Coastal and Marine Hazards and Resources Program CMHRP Pacific Coastal and Marine Science Center PCMSC Department of the Interior DOI Geographic Names Information System (GNIS) Pacific Ocean State of Washington Ozette Lake Ozette River None Olympic Wilderness No access constraints USGS-authored or produced data and information are in the public domain from the U.S. Government and are freely redistributable with proper metadata and source attribution. Please recognize and acknowledge the U.S. Geological Survey as the originator(s) of the dataset and in products derived from these data. U.S. Geological Survey, Pacific Coastal and Marine Science Center PCMSC Science Data Coordinator mailing and physical

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Santa Cruz CA 95060 831-427-4747 pcmsc_data@usgs.gov Paula J. Reimer William E.N. Austin Edouard Bard Alex Bayliss Paul G. Blackwell Christopher Bronk Ramsey Martin Butzin Hai Cheng R. Lawrence Edwards Michael Friedrich Pieter M. Grootes 2020 Reimer, P.J., Austin, W.E., Bard, E., Bayliss, A., Blackwell, P.G., Ramsey, C.B., Butzin, M., Cheng, H., Edwards, R.L., Friedrich, M., and Grootes, P.M., 2020, The IntCal20 Northern Hemisphere radiocarbon age calibration curve (0–55 cal kBP): Radiocarbon, vol. 62, p.725-757. https://doi.org/10.1017/RDC.2020.41 Quality control of attribute accuracy was conducted during field data collection, processing workflows and in compilation of this data release. No formal logical consistency tests were conducted. Dataset is considered complete for the information presented, as described in the abstract. Users are advised to read the rest of the metadata record carefully for additional details. Peter Dartnell Daniel S. Brothers Andrew C. Ritchie Brian Sherrod Jackson E. Currie Peter Dal Ferro Daniel C. Powers 2024 Raster Digital Dataset online U.S. Geological Survey https://doi.org/10.5066/P9U91FSB online database 20190714 20190717 ground condition at time data were collected. Dartnell and others, 2024 High resolution bathymetry data Sediment cores were collected throughout Ozette Lake, WA during USGS field activity 2019-622-FA and 2021-641-FA using either a Vibracorer (VC- labeled core ID), a gravity corer (GC- labeled core ID), or a mini-hammer corer (BC- labeled core ID). Water depths were derived from high resolution bathymetry (Dartnell and others, 2024). Sediment cores were sent to USGS Pacific Coastal and Marine Science Center (PCMSC) for processing and archiving. At PCMSC, cores were split and photographed using a Geotek multi-sensor core logger (MSCL) system. Cores over 1.5 m in length were split into multiple sections to permit scanning. Additional sampling of the split cores included grainsize analysis, X-ray fluorescence (XRF) scanning, and radiocarbon sampling to date stratigraphic ages. Dartnell and others, 2024 20240116 Where suitable material was present, samples from sediment layers of interest were collected and sent to the W.M. Keck Carbon Cycle Accelerator Mass Spectrometer (KCCAMS) Facility or the National Ocean Sciences Accelerator Mass Spectrometry (NOSAMS) Facility for radiocarbon dating. 20210320 W.M. Keck Carbon Cycle Accelerator Facility Department of Earth System Science University of California, Irvine mailing and physical

2222B Croul Hall

Irvine CA 92697 949-824-3674 jsouthon@uci.edu Point Point 93 0.000001 0.000001 Decimal Degrees WGS 1984 WGS 84 6378137.0 298.257224 Local surface 0.001 meters Attribute values OzetteLake.Radiocarbon.data.csv Comma-delimited text file containing radiocarbon age data for core samples. Producer defined Date Reported Date sample was measured National Ocean Sciences Accelerator Mass Spectrometry Facility (NOSAMS) or W.M. Keck Carbon Cycle Accelerator Mass Spectrometry Facility (KCCAMS) 08/14/2020 12/18/2022 Date in MM/DD/YYYY Core ID U.S. Geological Survey assigned core ID U.S. Geological Survey Unique core ID assigned in the field. Sample interval midpoint (cm) The midpoint of the sample interval in centimeters representing local core depth. U.S. Geological Survey 3.0 307.5 centimeters Submitter Identification Unique submitter identifier that combines the USGS Core ID and the local core depth sample interval in centimeters U.S. Geological Survey Unique core ID assigned in the field and local core depth sample interval in centimeters. Process Type of material sampled for radiocarbon. Producer defined Organic Carbon (OC) Accession Number Unique sample ID assigned by NOSAMS or KCCAMS National Ocean Sciences Accelerator Mass Spectrometry Facility (NOSAMS) or W.M. Keck Carbon Cycle Accelerator Mass Spectrometer Facility (KCCAMS) Unique sample ID Lab The lab that performed the radiocarbon analysis Producer defined NOSAMS National Ocean Sciences Accelerator Mass Spectrometry Facility Producer defined KCCAMS W.M. Keck Carbon Cycle Accelerator Mass Spectrometer Facility Producer defined Fraction modern Fraction of modern carbon in sample Producer defined 0.2112 0.9786 unitless ratio fraction modern error Standard error of measurement Producer defined 0.0009 0.0257 unitless ratio 14C age (years BP) Conventional carbon 14 age in years before present Producer defined 170 12490 years before present 14C age error One standard deviation error of 14C age measurement Producer defined 15 240 years before present D14C (per mille) carbon 14 depletion per mille. Entries with n.d. have indicates sample has no data for that attribute. Produce defined -788.80 -21.4 per mille D14C error carbon 14 depletion per mille error. Values of n/a indicate that no data is available. Producer defined. 0.9 25.7 per mille Sample Photo Name If a sample photo was logged for the particular sample interval, then this lists the name of the sample photo that in included in OzetteLake.radiocarbon.sample.photo.zip. Producer defined The name of the sample photo that in included in OzetteLake.radiocarbon.sample.photo.zip. If no sample photo was taken then n/a is listed. The first line of the csv file is a header line listing attribute labels. U.S. Geological Survey U.S. Geological Survey - CMGDS mailing and physical

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Santa Cruz CA 95060 1-831-427-4747 pcmsc_data@usgs.gov Radiocarbon age data are provided in a comma-delimited text file OzetteLake.radiocarbon.data.csv accompanied by CSDGM FGDC compliant metadata. Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. comma-delimited text 2022 Comma-delimited text file of radiocarbon age data. 0.0093 https://doi.org/10.5066/P9A0U8J7 Data can be downloaded using the Network_Resource_Name link and scrolling to the Environmental Data section. None. Radiocarbon age data in .csv format can be viewed with any standard table editing software (for example, Excel, Numbers). 20240615 U.S. Geological Survey, Pacific Coastal and Marine Science Center PCMSC Science Data Coordinator mailing and physical

2885 Mission Street

Santa Cruz CA 95060 831-427-4747 pcmsc_data@usgs.gov Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998