Kira Mizell Isabelle M. Shapiro 20250618 comma-delimited text data release DOI: 10.5066/P1PZ48WA Pacific Coastal and Marine Science Center, Santa Cruz, California U.S. Geological Survey Suggested Citation: Mizell, K. and Shapiro, I.M., 2025, X-ray diffraction data for the 0-2 cm horizons of marine sediment cores and a mineral concretion near waste barrels in the San Pedro Basin of the Southern California Borderland: U.S. Geological Survey data release, https://doi.org/10.5066/P1PZ48WA. https://doi.org/10.5066/P1PZ48WA Marine sediment push cores and one mineral concretion were collected near waste barrels in the San Pedro Basin of the Southern California Borderland in the Pacific Ocean using a remotely operated vehicle during the Schmidt Ocean Institute research cruise FK210726 onboard the R/V Falkor in 2021. Dried sediment samples of the 0-2 centimeter horizon of the cores and the mineral concretion were prepared at the USGS Pacific Coastal and Marine Science Center for powder x-ray diffraction analyses, and x-ray diffraction scan data are provided here. Location information (latitude, longitude, depth) for each sample are provided in each Attribute Definition of this metadata file. The x-ray diffraction work was funded by the U.S Geological Survey Pacific Coastal and Marine Science Center and ship time was funded by NOAA Office of Ocean Exploration and Research (grant number NA19OAR110305). These data serve to expand the knowledge of seafloor sediments offshore Southern California in regions where waste dumping has occurred. 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=2021-637-FA Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. 20210726 20250215 ground condition at the time data were collected Complete None planned -122.112342 -117.200932 33.761558 32.248276 ISO 19115 Topic Category oceans geoscientificInformation Data Categories for Marine Planning Nonliving Resources Physical/Chemical Features USGS Thesaurus X-ray diffraction marine geology chemical analysis Marine Realms Information Bank (MRIB) keywords basin mineralogy marine geology sedimentology coastal pollution dump site sedimentary waste disposal None U.S. Geological Survey USGS Coastal and Marine Hazards and Resources Program CMHRP Pacific Coastal and Marine Science Center PCMSC Global Ocean Mineral Resources USGS Metadata Identifier USGS:6838f0c7d4be0259257472b1 Geographic Names Information System (GNIS) Pacific Ocean NGA GEOnet Names Server (GNS) Southern California Borderland San Pedro Basin 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 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 Mac OS Ventura 13.7.4, Microsoft Excel 16.95.4 for Mac X-ray diffraction data were tested for accuracy by intermittently analyzing a powdered quartz reference sample to verify the one hundred intensity peak at 26.6 degree two-theta. When the quartz peak was in the proper position, we infer that other measured peak positions in the sample are accurate. Peak intensities are considered semiquantitative since no quantitative standards were analyzed for this dataset. 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. A formal accuracy assessment of the horizontal positional information in the dataset has not been conducted. The horizontal accuracy was determined with the ship's GPS navigation, which is accurate to less than 5 m. A formal accuracy assessment of the vertical positional information in the dataset has not been conducted. Levin, Lisa 2021 https://www.marine-geo.org/tools/files/30410#datasets Marine Geoscience Data System 20210726 20210805 ground condition at time samples were collected FK210726 cruise data Latitude, longitude, and depth information for FK210726 samples Push core samples and one mineral concretion sample were collected near waste barrels in San Pedro Basin of the Southern California Borderland in the Pacific Ocean onboard the R/V Falkor between July 26, 2021, and August 5, 2021, during the FK210726 research expedition. Push cores and the mineral concretion were recovered by the manipulator arm of ROV SubBastian. 20210805 On board ship, sediment cores were extruded and sliced into four 2 cm depth horizons. Aliquots of the 0-2 cm horizon were homogenized with alcohol-sterilized spatula and frozen at -20 degrees Celcius in Whirlpakÿbag. 20210805 On board ship, the mineral concretion was recovered from the ROV and stored in a plastic bag at room temperature. 20210805 At Scripps Institution of Oceanography, approximately 2 grams of the frozen 0-2 cm horizon sediment aliquots were thawed in a sterile petri dish and air-dried overnight in a sterile flow hood. The sediment was then homogenized with mortar and pestle and shipped to the USGS Pacific Coastal and Marine Science Center at ambient temperature. 20240615 Johanna Gutleben Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego postdoctoral researcher mailing

Kaplan Lab, Room 201, 9500 Gilman Drive, Mail Code 0209

San Diego CA 92093-0209 858-534-7322 jgutleben@ucsd.edu At the USGS Marine Minerals Lab, the mineral concretion was rinsed with deionized water, air-dried overnight in a flow hood in a watch glass, and ground with a mortar and pestle to approximately 75 micrometer fineness. 20211010 At the USGS Pacific Coastal and Marine Science Center Marine Minerals Lab powdered sediment and mineral concretion samples were backloaded and tamped into sample holders and run in a Panalytical X Pert3 x-ray diffractometer (XRD; https://www.malvernpanalytical.com/) with Cu K-alpha radiation and graphite monochromator. XRD scans were collected using the following parameters: step size of 0.017 degrees two-theta between 5 and 70 degrees two-theta, power of 40 kilovolt and 45 milliampere, scan rate of 60 seconds per step, a sample holder rotational speed of 0.03 degrees per second, and averaged triplicate scans at three different stage wobble angles (-1, 0, and 1 degree). 20250319 X-ray diffraction scan data were combined into a comma-delimited text values document (FK210726_SCB_barrel_sediment_XRD_data.csv). FK210726 cruise data 20250306 Point Point 3823 0.00000001 0.0000001 Decimal degrees D_WGS_1984 WGS_1984 6378137.0 298.257222356 FK210726_SCB_barrel_sediment_XRD_data.csv Comma-delimited file containing results from x-ray diffraction analyses of the 0-2 cm horizon of marine sediment core samples and one mineral concretion. Location information for the samples are included in each Attribute Definition of this metadata file and not the data table. The header for each column of diffraction data is a sample name. The sediment sample names follow the scheme of SCB, indicating Southern California Borderland, followed by a hyphen, followed by the push core ID and sediment horizon ID, which is represented by a combination of numbers and letters. The mineral concretion sample is simply labeled as such. Producer defined Position_2theta The two-theta angle at which the x-ray diffractometer measured the X-ray diffraction of the powdered sample instrument defined 5.0084 69.9824 degrees 0.0001 SCB-274bA X-ray diffraction intensity value at the two-theta angle listed in the corresponding row in the Position attribute. The location for sample SCB-274bA is 33.57358835, -118.4360591 and 900.61 m water depth. producer defined 17.4747 879.738 counts 0.0001 SCB-290cA X-ray diffraction intensity value at the two-theta angle listed in the corresponding row in the Position attribute. The location for sample SCB-290cA is 33.56600101, -118.4242769 and 901.13 m water depth. producer defined 16.5936 922.0925 counts 0.0001 SCB-292bA X-ray diffraction intensity value at the two-theta angle listed in the corresponding row in the Position attribute. The location for sample SCB-292bA is 33.56605059, -118.4242526 and 901.02 m water depth. producer defined 19.5928 733.6876 counts 0.0001 SCB-298cA X-ray diffraction intensity value at the two-theta angle listed in the corresponding row in the Position attribute. The location for sample SCB-298cA is 33.56610603, -118.425657 and 901.29 m water depth. producer defined 20.4561 779.6876 counts 0.0001 SCB-300bA X-ray diffraction intensity value at the two-theta angle listed in the corresponding row in the Position attribute. The location for sample SCB-300bA is 33.56610595, -118.425668 and 901.28 m water depth. producer defined 18.8807 736.5314 counts 0.0001 SCB-308cA X-ray diffraction intensity value at the two-theta angle listed in the corresponding row in the Position attribute. The location for sample SCB-308cA is 33.56608822, -118.4269999 and 901.41 m water depth. producer defined 15.2360 903.9075 counts 0.0001 SCB-310bA X-ray diffraction intensity value at the two-theta angle listed in the corresponding row in the Position attribute. The location for sample SCB-310bA is 33.56608617, -118.4269759 and 901.4 m water depth. producer defined 20.6746 746.6000 counts 0.0001 Barrel_3S_Mineral_Concretion X-ray diffraction intensity value at the two-theta angle listed in the corresponding row in the Position attribute. The location for sample Barrel_3S_Mineral_Concretion is 33.56608617, -118.4269759 and 901.4 m water depth. producer defined 21.3740 1421.6797 counts 0.0001 The first line of the csv file is a header line. U.S. Geological Survey U.S. Geological Survey - ScienceBase mailing and physical

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Denver CO 80225 1-888-275-8747 sciencebase@usgs.gov These data are available in .csv format contained in a single file. 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 Microsoft Excel 16.16.17 for Mac File contains table in .csv format No compression applied 0.30187 https://www.sciencebase.gov/catalog/file/get/6838f0c7d4be0259257472b1 https://www.sciencebase.gov/catalog/item/6838f0c7d4be0259257472b1 https://doi.org/10.5066/P1PZ48WA Data can be downloaded using the Network_Resource_Name links. The first link is a direct link to download a zipped file of data and metadata. The second link points to a landing page with metadata and data. The third link points to the landing page for the entire data release. None. These data can be viewed with Microsoft Excel or any text reader. 20250618 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