Daniel J. Kennedy Maureen A. Walton Guy R. Cochrane Charlie Paull Roberto Gwiazda Thomas D. Lorenson Jason A. Addison Eve Lundsten 20211016 comma-delimited text data release DOI:10.5066/P9DE639J Pacific Coastal and Marine Science Center, Santa Cruz, California U.S. Geological Survey https://doi.org/10.5066/P9DE639J Daniel J. Kennedy Maureen A. Walton Guy R. Cochrane Charlie Paull Roberto Gwiazda Thomas D. Lorenson Jason A. Addison Eve Lundsten 2021 data release DOI:10.5066/P9DE639J Pacific Coastal and Marine Science Center, Santa Cruz, CA U.S. Geological Survey https://doi.org/10.5066/P9DE639J This dataset includes concentrations chloride and sulfate in porewater from piston and gravity cores collected in September 2019 offshore of south-central California aboard the R/V Bold Horizon. This dataset is one of several collected as part of the Bureau of Ocean Energy Management (BOEM)-funded California Deepwater Investigations and Groundtruthing (Cal DIG I) project. The purpose of the study is to assess shallow geohazards, benthic habitats, and thereby the potential for alternative energy infrastructure (namely floating wind turbines) offshore south-central California due to its proximity to power grid infrastructure associated with the Morro Bay power plant. These core data provide information about the geology of the seafloor and shallow subsurface offshore of the south-central California coast. This dataset was collected in order to identify shallow geohazards, benthic habitats, and thereby the potential for alternative energy infrastructure (namely floating wind turbines) offshore south-central California due to its proximity to power grid infrastructure associated with the Morro Bay power plant. Additional information about the USGS field activity from which these data were derived is available online at: https://cmgds.marine.usgs.gov/fan_info.php?fan=2019-642-FA Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this Federal Geographic Data Committee-compliant metadata file is intended to document the data set in nonproprietary form, as well as in Esri format, this metadata file may include some Esri-specific terminology. 20190927 ground condition at the time the samples were collected Complete None planned -121.106945 -121.869382 35.782235 34.535102 USGS Metadata Identifier USGS:ae53dc9b-b9d1-47cf-aa48-4287588897e3 ISO 19115 Topic Category geoscientificInformation Data Categories for Marine Planning Nonliving resources Physical/Chemical Features Substrate Physical Habitats and Geomorphology USGS Thesaurus core analysis coastal processes hazards Marine Realms Information Bank (MRIB) keywords sediment submarine landslides None U.S. Geological Survey USGS Coastal and Marine Hazards and Resources Program CMHRP Pacific Coastal and Marine Science Center PCMSC Geographic Names Information System (GNIS) Pacific Ocean Diablo Canyon Morro Bay None 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 (USGS) as the originator 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

2885 Mission Street

Santa Cruz CA 95060 831-427-4747 pcmsc_data@usgs.gov 2019-642-FA_core_thumbnail.png Bathymetry map of study area with sample sites in purple png No formal attribute accuracy tests were conducted No formal logical accuracy 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. The locations of samples were determined using the Bold Horizon's internal Yonav navigation system, no other formal positional accuracy tests were conducted. No vertical positional accuracy tests were conducted Piston and gravity cores were collected at sea aboard the R/V Bold Horizon on U.S. Geological Survey (USGS) cruise 2019-642-FA in conjunction with the Monterey Bay Aquarium Research Institute (MBARI). 20190927 Porewater samples were collected at intervals throughout each core using porous ceramic tubes connected to an evacuated small volume syringe at one end and inserted into the cores at the other end to extract pore waters through vacuum action. Porewater samples were filtered through 0.22-µmfilters, diluted 1:100, and injected into a Dionex DX-120 ion chromatograph. Bracketing standards were run every five samples. Long-term reproducibility of Cl concentration measurements is 3.2% (2s). 20200320 Roberto Gwiazda Monterey Bay Aquarium Research Institute (MBARI) Research Specialist mailing and physical

7700 Sandholdt Road

Moss Landing CA 95039 831-775-1828 rgwiazda@mbari.org Point Point 324 0.00001 0.00001 Decimal degrees D_WGS_1984 WGS_1984 6378137.0 298.257223563 North American Vertical Datum of 1927 0.1 meters Explicit elevation coordinate included with horizontal coordinates 2019-642-FA_porewater.csv Porewater data spreadsheet Producer defined Core Core sample from which porewater was sampled Monterey Bay Aquarium Research Institute (MBARI) Unique identifier for the core sample given in the field, where GC=gravity core and JPC=jumbo piston core Depth cm Depth from top of core at which the porewater was sampled Monterey Bay Aquarium Research Institute (MBARI) 30 717 cm 0.1 Porewater Chloride millimolar Chloride concentration per core segment Monterey Bay Aquarium Research Institute (MBARI) 514.6 564.5 g/mMa 0.1 Porewater Sulfate millimolar Sulfate concentration per core segment Monterey Bay Aquarium Research Institute (MBARI) 0 28.6 g/mMa 0.1 The first line of the csv file is a header line. U.S. Geological Survey U.S. Geological Survey - CMGDS PCMSC Science Data Coordinator mailing and physical

2885 Mission Street

Santa Cruz CA 95060 831-427-4747 pcmsc_data@usgs.gov 2019-642-FA_porewater.csv containing Chloride and Sulfate porewater concentrations. The data are divided up and presented by core sample, as reflected in the individual file name(s). 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 NA 2019-642-FA_porewater.csv containing Chloride and Sulfate porewater concentrations. The data are divided up and presented by core sample, as reflected in the individual file name(s). no compression used 0.007 https://doi.org/10.5066/P9DE639J Data can be downloaded using the Network_Resource_Name links then scrolling down to the Sampling Data section. None. These data can be viewed with Excel or any text-reading software. 20211016 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