Ferdinand K.J. Oberle Cordell D. Johnson Thomas D. Lorenson Angela C. Tan Bruce M. Richmond 20260424 comma-delimited text data release DOI:10.5066/P14FZKEF Pacific Coastal and Marine Science Center, Santa Cruz, California U.S. Geological Survey Suggested Citation: Oberle, F.K.J., Johnson, C., Lorenson, T.D., Tan, A.C., Richmond, B.M., 2026, Grain size analysis and total carbon content of augered sediment samples from Barter Island, Alaska: U.S. Geological Survey data release, https://doi.org/10.5066/P14FZKEF. https://doi.org/10.5066/P14FZKEF This data release contains grain size and total carbon analysis of sediment samples from 1 inch hand-augered cores collected from Barter Island, Alaska. These data were collected in 2016 and 2019 (USGS Field Activity 2016-645-FA and 2019-634-FA). Data include location information (latitude, longitude, depth), and the weight percent of 65 phi bins, four size fractions (gravel, sand, silt, clay), total carbon, inorganic carbon, organic carbon, and calcium carbonate. Data were obtained to characterize downcore sedimentological and geochemical properties of sediments. These data are intended for science researchers, students, policy makers, and the general public. Additional information about the field activity or activities from which these data were derived is available online at: https://cmgds.marine.usgs.gov/fan_info.php?fan=2016-645-FA https://cmgds.marine.usgs.gov/fan_info.php?fan=2019-634-FA Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. 20160525 20190907 Ground condition at time data were collected Complete None planned -143.689379 -143.648714 70.133852 70.131969 ISO 19115 Topic Category oceans geoscientificInformation Data Categories for Marine Planning Nonliving Resources Material Resources Physical/Chemical Features USGS Thesaurus augering rotary drilling grain-size analysis chemical analysis earth sciences marine geology Marine Realms Information Bank (MRIB) keywords sediment geochemistry None U.S. Geological Survey USGS Coastal and Marine Hazards and Resources Program CMHRP Pacific Coastal and Marine Science Center USGS Metadata Identifier USGS:69e1403ab66b01441bb3aa46 Geographic Names Information System (GNIS) Barter Island State of Alaska 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. These data are marked with a Creative Common CC0 1.0 Universal License. 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

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Santa Cruz CA 95060 831-427-4747 pcmsc_data@usgs.gov https://www.sciencebase.gov/catalog/file/get/69e1403ab66b01441bb3aa46?name=Augering 2 BI052016.jpg&allowOpen=true Push core sediment collection with a remotely operated vehicle. JPEG Work was funded by the U.S. Geological Survey Coastal and Marine Hazards Program. Windows 11 Enterprise, Microsoft Excel 365 for enterprise Beckman-Coulter 2011 publication Beckman-Coulter, 2011, Instructions for Use: LS 13 320 Laser Diffraction Particle Size Analyzer: Brea, Calif., Beckman-Coulter, 246 p. https://www.beckmancoulter.com/wsrportal/techdocs?docname=b05577ab.pdf Robert E. Carver 1971 publication Carver, R.E., 1971, Procedures in Sedimentary Petrology: Wiley Interscience, New York: 49-94. https://tamug-ir.tdl.org/handle/1969.3/21450 E. E. Collias M. R. Rona D. A. McManus J. S. Creager 1963 publication Collias, E.E., Rona, M.R., McManus, D.A., and Creager, J.S., 1963, Machine processing of geological data: Department of Oceanography, University of Washington, Technical Report No. 87, 119 p. https://apps.dtic.mil/sti/pdfs/AD0423746.pdf Robert Louis Folk 1974 publication Folk, R.L., 1974, Petrology of Sedimentary Rocks: Hemphill Publishing Co., Austin, TX, 182 p. https://tamug-ir.tdl.org/handle/1969.3/21435 Robert Louis Folk 1980 publication Folk, R.L., 1980, Petrology of Sedimentary Rocks: Hemphill Publishing Co., Austin, TX, 184 p. https://repositories.lib.utexas.edu/bitstream/handle/2152/22930/folkpetrology.pdf?sequence=3 Robert Louis Folk 1966 publication Folk, R.L.,1966, A review of grain-size parameters: Sedimentology, 6, 73-93. https://doi.org/10.1111/j.1365-3091.1966.tb01572.x Robert Louis Folk William C. Ward 1957 publication Folk, R.L., and Ward, W.C., 1957, Brazos River bar; a study in the significance of grain size parameters: Journal of Sedimentary Research, 27, 3-26. https://doi.org/10.1306/74D70646-2B21-11D7-8648000102C1865D Douglas Lamar Inman 1952 publication Inman, D.L., 1952, Measures for describing the size distribution of sediments: Journal of Sedimentary Research, 22, 125-145. https://doi.org/10.1306/D42694DB-2B26-11D7-8648000102C1865D J.M. Jaquet J.P. Vernet 1976 publication Jaquet J.M., and Vernet J.P., 1976, Moment and graphic size parameters in sediments of Lake Geneva (Switzerland): Journal of Sedimentary Petrology, 46, 305-312. https://doi.org/10.1306/212F6F46-2B24-11D7-8648000102C1865D Penscil Inc. 2015 publication Penscil Inc., 2015, pcSDSZ: Sediment Size Analysis Software for Windows Operation Manual Version 2.00, prepared for USGS Coastal and Marine Geology. Unpublished document. Parker D. Trask 1930 publication Trask, P.D., 1930, Mechanical analyses of sediments by centrifuge: Economic Geology, 25, p. 581-599. https://doi.org/10.2113/gsecongeo.25.6.581 Parker D. Trask 1932 publication Trask, P. D., 1932, Origin and environment of source sediments of petroleum: Gulf Publishing Company, Houston, Texas. 323 p. https://www.cambridge.org/core/journals/journal-of-the-marine-biological-association-of-the-united-kingdom/article/abs/origin-and-environment-of-source-sediments-of-petroleum-by-d-trask-parker-assisted-by-harold-e-hammar-and-c-c-wu-gulf-publishing-co-houston-texas-323-pp-1932/E4212BACC9A798808CC166A1DE4CF691#article UIC Inc. 2022 publication UIC Inc., Operation Manual Model CM5017 CO2 Coulometer, Joliet, IL, 2.0, 28-30. UIC Inc. 2022 publication UIC Inc., Operation Manual Model CM5200 Autosampler Furnace, Joliet, IL, 2.4, 13 p. For grain-size analyses, annual service tests and daily calibrations with reference standards ensured that the Beckman Coulter LS 13 320 operated within specifications (Beckman-Coulter, 2011). Each sample was analyzed three times by the instrument and the data were averaged. In addition, a lab procedural duplicate was run with each batch of samples to ensure consistency and values were within 15 percent. For total carbon and total inorganic carbon analyses, duplicates were run for each sample and the results were averaged. PCMSC ensured that the instrument was within specifications by running blanks and pure, reagent-grade calcium carbonate standard before and after every 10 samples. A lab procedural duplicate was run with each batch of samples to ensure consistency and values were within 15 percent. The value -9999 indicates that data are not available. Data values are within the expected value range. 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. Point locations were collected with a handheld Garmin GPSMAP 76CS receiver using differential correction. According to manufacturer specifications, positional accuracy with differential correction is typically 3 to 5 meters at 95 percent confidence using United States Coast Guard differential correction, and less than 3 meters at 95 percent confidence using Wide Area Augmentation System correction. No formal positional accuracy tests were conducted. Sampling depth below the ground surface was determined by summing the inserted lengths of the auger drill bit and the successive extension rods advanced during ground penetration. Sediment samples were collected from permafrost coastal bluff locations from Barter Island, Alaska using a Skidril GD16EF 2-cycle gas-powered hammer drill fitted with an AMS 5/8 inch threaded flighted auger kit. Samples were obtained at 0.5 m intervals from the surface to a maximum depth of 8 meters or less. Sediment auger sampling locations were recorded using a handheld Garmin GPSMAP 76CS receiver using differential correction. 20190907 In the USGS Pacific Coastal and Marine Science Center (PCMSC) Core Preparation and Analysis Laboratory, subsamples were collected from the field samples. 20191006 Ferdinand Oberle USGS Research Geologist mailing and physical

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Santa Cruz CA 95060 831-460-7589 foberle@usgs.gov Grain-size analysis was conducted by the USGS Pacific Coastal and Marine Science Center (PCMSC) Sediment Lab Suite and Carbon Analysis Laboratory using a Beckman Coulter LS 13 320 particle size analyzer with an aqueous liquid module attachment. PCMSC procedures are modified from those described in Carver (1971) and Folk (1974, 1980). 5-50 grams of sediment was sub-sampled and at least 10 milliliters of 30 percent hydrogen peroxide was added to oxidize overnight to remove organics. The samples were then heated to 250 degrees Celsius to drive off excess hydrogen peroxide. Next, samples were placed in an ultrasonic bath to help disperse silt and clay (mud) from sand and larger-sized particles. Samples were then rinsed twice in deionized water with centrifugation to remove soluble ions. Subsequently, the samples were wet sieved with 1 millimeter and 0.063 millimeter sieves to segregate the combined gravel and coarse sand fraction (greater than 1 millimeter), sand (1 millimeter to 0.063 millimeter), and mud (less than 0.063 millimeter). The coarse sand + gravel fractions were then dried, dry sieved at 1/4phi intervals and weighed (Carver, 1971). The sand fraction was dried and weighed. The mud fraction was collected in a 1 liter graduated cylinder, 5 milliliters of at least 10 percent sodium hexametaphosphate (dispersant) was added, and deionized water was added to bring the total the volume to 1 liter. The mud + dispersant solution sat overnight to ensure complete dispersion and to observe if flocculation occurred. Subsequently, a 20 milliliter aliquot was extracted from the graduated cylinder and dried to obtain the mud fraction weight normalized to a 1-liter basis. The mud and sand fractions were analyzed separately via the Beckman Coulter LS 13 320 with the aqueous liquid module attachment. All size fraction data were compiled and converted by the PCMSC Sediment Lab Suite and Carbon Analysis Laboratory pcSDSZ program version 1.71 (Penscil, 2015) to a grain-size distribution at 1/4phi size intervals on a weight percent basis. pcSDSZ also calculated interpolated sizes and graphical statistics on a percent coarser basis (Folk and Ward, 1957; Folk, 1966; Folk, 1974, 1980; Inman, 1952; Trask, 1930, 1932) and moment measures (Collias and others, 1963; Jaquet and Vernet, 1976; Folk 1980). 20191008 Angela Tan USGS Physical Scientist mailing and physical

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Santa Cruz CA 95060 831-460-7409 atan@usgs.gov Grain sizes at select cumulative percentage values (D) were calculated by the USGS Pacific Coastal and Marine Science Center (PCMSC) Sediment Lab Suite and Carbon Analysis Laboratory software pcSDSZ version 1.71 on a percent coarser basis, which summed from coarse to fine bins. D values were interpolated between phi bins bracketing the specified D value. Grain sizes were converted into units of millimeters (mm) using the formula mm=reciprocal of 2(exponent)phi or (phi=-log2(mm)). Interpolated grain sizes at D5, D10, D16, D25, D50, D75, D84, D90, and D95 are reported in phi and millimeter units. 20191008 Angela Tan USGS Physical Scientist mailing and physical

2885 Mission Street

Santa Cruz CA 95060 831-460-7409 atan@usgs.gov Total carbon and total inorganic carbon of bulk sediment were determined coulometrically (UIC, Inc.) at the USGS Pacific Coastal and Marine Science Center (PCMSC) Sediment Lab Suite and Carbon Analysis Laboratory. Samples were run in duplicate. Coulometer performance was verified relative to a calcium carbonate reference material. Total organic carbon content (TOC) was calculated as the difference between total carbon and total inorganic carbon. Calcium carbonate was calculated as percent TIC * 8.333. 20191008 Angela Tan USGS Physical Scientist mailing and physical

2885 Mission Street

Santa Cruz CA 95060 831-460-7409 atan@usgs.gov Results from all analyses and core location information were combined into a single comma-delimited text value document (Barter_Island_GrainSize_and_Carbon.csv). 20260415 Ferdinand K.J. Oberle USGS Research Geologist mailing and physical

2885 Mission Street

Santa Cruz CA 95060 831-460-7589 foberle@usgs.gov Point Point 56 0.0001 0.0001 Decimal degrees D_WGS_1984 WGS_1984 6378137.0 298.257222101 Barter_Island_GrainSize_and_Carbon.csv Comma-delimited file containing results from grain size and total carbon analysis of sediment samples at the latitude, longitude, and water depth of each sample location. The value -9999 indicates that data are not available. Producer defined Sample_ID The sample ID for each sample Producer defined Sample IDs for augered samples. Sample identifiers are formatted as BGM [Bear Gulch Main] or BI-X [Barter Island], where X represents the [borehole identification], followed by [depth in meters]. For example, BGM 1.0m is [Bearh Gulch Main at a depth of 1.0m]. Duplicate analyses are indicated by "duplicate" appended to the Sample ID. Subsample_Depth_Interval The subsample depth interval for each sample in meters producer defined The sampling depth range measured in meters below the surface. For example, the value 4.5-4.6 indicates that a sediment sample was collected representing the sediment between 4.5-4.6 meters depth below the surface. Latitude Datum_WGS_1984 Latitude at which sample was collected producer defined 70.13210000 70.13341997 decimal degrees .00000001 Longitude Datum_WGS_1984 Longitude at which sample was collected producer defined -143.68689 -143.65251 decimal degrees .00001 Date_Collected Date sediment samples were collected in field in month/day/year format. producer defined 5/25/2016 09/07/2019 mm/dd/yyyy 1 -4.00phi_16mm Weight percent of sample with grain diameter greater than -4.00 phi, or 16 mm and less than the floor of the next largest diameter bin. producer defined .00 36.59 percent .01 -3.75phi_13.5mm Weight percent of sample with grain diameter greater than -3.75 phi, or 13.5 mm and less than the floor of the next largest diameter bin. producer defined .00 .00 percent .01 -3.50phi_11.2mm Weight percent of sample with grain diameter greater than -3.50 phi, or 11.2 mm and less than the floor of the next largest diameter bin. producer defined .00 7.64 percent .01 -3.25phi_9.51mm Weight percent of sample with grain diameter greater than -3.25 phi, or 9.51 mm and less than the floor of the next largest diameter bin. producer defined .00 5.03 percent .01 -3.00phi_8mm Weight percent of sample with grain diameter greater than -3.00 phi, or 8 mm and less than the floor of the next largest diameter bin. producer defined .00 4.65 percent .01 -2.75phi_6.73mm Weight percent of sample with grain diameter greater than -2.75 phi, or 6.73 mm and less than the floor of the next largest diameter bin. producer defined .00 6.76 percent .01 -2.50phi_5.66mm Weight percent of sample with grain diameter greater than -2.50 phi, or 5.66 mm and less than the floor of the next largest diameter bin. producer defined .00 3.28 percent .01 -2.25phi_4.76mm Weight percent of sample with grain diameter greater than -2.25 phi, or 4.76 mm and less than the floor of the next largest diameter bin. producer defined .00 4.36 percent .01 -2.00phi_4mm Weight percent of sample with grain diameter greater than -2.00 phi, or 4 mm and less than the floor of the next largest diameter bin. producer defined .00 4.92 percent .01 -1.75phi_3.36mm Weight percent of sample with grain diameter greater than -1.75 phi, or 3.36 mm and less than the floor of the next largest diameter bin. producer defined .00 4.95 percent .01 -1.50phi_2.83mm Weight percent of sample with grain diameter greater than -1.50 phi, or 2.83 mm and less than the floor of the next largest diameter bin. producer defined .00 1.82 percent .01 -1.25phi_2.38mm Weight percent of sample with grain diameter greater than -1.25 phi, or 2.38 mm and less than the floor of the next largest diameter bin. producer defined .00 1.70 percent .01 -1.00phi_2mm Weight percent of sample with grain diameter greater than -1.00 phi, or 2 mm and less than the floor of the next largest diameter bin. producer defined .00 1.31 percent .01 -0.75phi_1.68mm Weight percent of sample with grain diameter greater than -0.75 phi, or 1.68 mm and less than the floor of the next largest diameter bin. producer defined .00 1.12 percent .01 -0.50phi_1.41mm Weight percent of sample with grain diameter greater than -0.50 phi, or 1.41 mm and less than the floor of the next largest diameter bin. producer defined .00 1.30 percent .01 -0.25phi_1.19mm Weight percent of sample with grain diameter greater than -0.25 phi, or 1.19 mm and less than the floor of the next largest diameter bin. producer defined .00 1.49 percent .01 0.00phi_1mm Weight percent of sample with grain diameter greater than 0.00 phi, or 1 mm and less than the floor of the next largest diameter bin. producer defined .00 2.76 percent .01 0.25phi_0.8409mm Weight percent of sample with grain diameter greater than 0.25 phi, or 0.8409 mm and less than the floor of the next largest diameter bin. producer defined .00 4.86 percent .01 0.50phi_0.7071mm Weight percent of sample with grain diameter greater than 0.50 phi, or 0.7071 mm and less than the floor of the next largest diameter bin. producer defined .00 7.16 percent .01 0.75phi_0.5946mm Weight percent of sample with grain diameter greater than 0.75 phi, or 0.5946 mm and less than the floor of the next largest diameter bin. producer defined .00 9.22 percent .01 1.00phi_0.5mm Weight percent of sample with grain diameter greater than 1.00 phi, or 0.5 mm and less than the floor of the next largest diameter bin. producer defined .00 10.27 percent .01 1.25phi_0.4204mm Weight percent of sample with grain diameter greater than 1.25 phi, or 0.4204 mm and less than the floor of the next largest diameter bin. producer defined .00 9.54 percent .01 1.50phi_0.3536mm Weight percent of sample with grain diameter greater than 1.50 phi, or 0.3536 mm and less than the floor of the next largest diameter bin. producer defined .00 10.04 percent .01 1.75phi_0.2973mm Weight percent of sample with grain diameter greater than 1.75 phi, or 0.2973 mm and less than the floor of the next largest diameter bin. producer defined .00 10.73 percent .01 2.00phi_0.25mm Weight percent of sample with grain diameter greater than 2.00 phi, or 0.25 mm and less than the floor of the next largest diameter bin. producer defined .00 9.96 percent .01 2.25phi_0.2102mm Weight percent of sample with grain diameter greater than 2.25 phi, or 0.2102 mm and less than the floor of the next largest diameter bin. producer defined .01 8.72 percent .01 2.50phi_0.1768mm Weight percent of sample with grain diameter greater than 2.50 phi, or 0.1768 mm and less than the floor of the next largest diameter bin. producer defined .02 8.37 percent .01 2.75phi_0.1487mm Weight percent of sample with grain diameter greater than 2.75 phi, or 0.1487 mm and less than the floor of the next largest diameter bin. producer defined .06 8.95 percent .01 3.00phi_0.125mm Weight percent of sample with grain diameter greater than 3.00 phi, or 0.125 mm and less than the floor of the next largest diameter bin. producer defined .12 8.66 percent .01 3.25phi_0.1051mm Weight percent of sample with grain diameter greater than 3.25 phi, or 0.1051 mm and less than the floor of the next largest diameter bin. producer defined .14 7.99 percent .01 3.50phi_0.088388mm Weight percent of sample with grain diameter greater than 3.50 phi, or 0.088388 mm and less than the floor of the next largest diameter bin. producer defined .21 7.45 percent .01 3.75phi_0.074325mm Weight percent of sample with grain diameter greater than 3.75 phi, or 0.074325 mm and less than the floor of the next largest diameter bin. producer defined .40 7.87 percent .01 4.00phi_0.0625mm Weight percent of sample with grain diameter greater than 4.00 phi, or 0.0625 mm and less than the floor of the next largest diameter bin. producer defined .39 7.27 percent .01 4.25phi_0.052556mm Weight percent of sample with grain diameter greater than 4.25 phi, or 0.052556 mm and less than the floor of the next largest diameter bin. producer defined .18 5.87 percent .01 4.50phi_0.044194mm Weight percent of sample with grain diameter greater than 4.50 phi, or 0.044194 mm and less than the floor of the next largest diameter bin. producer defined .09 4.60 percent .01 4.75phi_0.037163mm Weight percent of sample with grain diameter greater than 4.75 phi, or 0.037163 mm and less than the floor of the next largest diameter bin. producer defined .06 4.38 percent .01 5.00phi_0.03125mm Weight percent of sample with grain diameter greater than 5.00 phi, or 0.03125 mm and less than the floor of the next largest diameter bin. producer defined .07 4.20 percent .01 5.25phi_0.026278mm Weight percent of sample with grain diameter greater than 5.25 phi, or 0.026278 mm and less than the floor of the next largest diameter bin. producer defined .17 4.15 percent .01 5.50phi_0.022097mm Weight percent of sample with grain diameter greater than 5.50 phi, or 0.022097 mm and less than the floor of the next largest diameter bin. producer defined .45 4.43 percent .01 5.75phi_0.018581mm Weight percent of sample with grain diameter greater than 5.75 phi, or 0.018581 mm and less than the floor of the next largest diameter bin. producer defined .41 4.61 percent .01 6.00phi_0.015625mm Weight percent of sample with grain diameter greater than 6.00 phi, or 0.015625 mm and less than the floor of the next largest diameter bin. producer defined .40 4.89 percent .01 6.25phi_0.013139mm Weight percent of sample with grain diameter greater than 6.25 phi, or 0.013139 mm and less than the floor of the next largest diameter bin. producer defined .44 5.37 percent .01 6.50phi_0.011049mm Weight percent of sample with grain diameter greater than 6.50 phi, or 0.011049 mm and less than the floor of the next largest diameter bin. producer defined 0.49 5.64 percent .01 6.75phi_0.009291mm Weight percent of sample with grain diameter greater than 6.75 phi, or 0.009291 mm. producer defined .52 5.65 percent .01 7.00phi_0.007813mm Weight percent of sample with grain diameter greater than 7.00 phi, or 0.007813 mm and less than the floor of the next largest diameter bin. producer defined .54 5.47 percent .01 7.25phi_0.00657mm Weight percent of sample with grain diameter greater than 7.25 phi, or 0.00657 mm and less than the floor of the next largest diameter bin. producer defined .53 5.20 percent .01 7.50phi_0.005524mm Weight percent of sample with grain diameter greater than 7.50 phi, or 0.005524 mm and less than the floor of the next largest diameter bin. producer defined .50 5.15 percent .01 7.75phi_0.004645mm Weight percent of sample with grain diameter greater than 7.75 phi, or 0.004645 mm and less than the floor of the next largest diameter bin. producer defined .46 4.92 percent .01 8.00phi_0.003906mm Weight percent of sample with grain diameter greater than 8.00 phi, or 0.003906 mm and less than the floor of the next largest diameter bin. producer defined .42 4.81 percent .01 8.25phi_0.003285mm Weight percent of sample with grain diameter greater than 8.25 phi, or 0.003285 mm and less than the floor of the next largest diameter bin. producer defined .39 4.62 percent .01 8.50phi_0.002762mm Weight percent of sample with grain diameter greater than 8.50 phi, or 0.002762 mm and less than the floor of the next largest diameter bin. producer defined 0.34 4.25 percent .01 8.75phi_0.002323mm Weight percent of sample with grain diameter greater than 8.75 phi, or 0.002323 mm and less than the floor of the next largest diameter bin. producer defined .32 3.97 percent .01 9.00phi_0.001953mm Weight percent of sample with grain diameter greater than 9.00 phi, or 0.001953 mm and less than the floor of the next largest diameter bin. producer defined .31 3.69 percent .01 9.25phi_0.001642mm Weight percent of sample with grain diameter greater than 9.25 phi, or 0.001642 mm and less than the floor of the next largest diameter bin. producer defined .30 3.41 percent .01 9.50phi_0.001381mm Weight percent of sample with grain diameter greater than 9.50 phi, or 0.001381 mm and less than the floor of the next largest diameter bin. producer defined .30 3.32 percent .01 9.75phi_0.001161mm Weight percent of sample with grain diameter greater than 9.75 phi, or 0.001161 mm and less than the floor of the next largest diameter bin. producer defined .29 3.27 percent .01 9.99phi_0.000983mm Weight percent of sample with grain diameter greater than 9.99 phi, or 0.000983 mm and less than the floor of the next largest diameter bin. producer defined .26 3.04 percent .01 10.25phi_0.000821mm Weight percent of sample with grain diameter greater than 10.25 phi, or 0.000821 mm and less than the floor of the next largest diameter bin. producer defined .24 2.97 percent .01 10.50phi_0.000691mm Weight percent of sample with grain diameter greater than 10.50 phi, or 0.000691 mm and less than the floor of the next largest diameter bin. producer defined .19 2.50 percent .01 10.75phi_0.000581mm Weight percent of sample with grain diameter greater than 10.75 phi, or 0.000581 mm and less than the floor of the next largest diameter bin. producer defined .16 2.03 percent .01 10.99phi_0.000492mm Weight percent of sample with grain diameter greater than 10.99 phi, or 0.000492 mm and less than the floor of the next largest diameter bin. producer defined .11 1.42 percent .01 11.25phi_0.000411mm Weight percent of sample with grain diameter greater than 11.25 phi, or 0.000411 mm and less than the floor of the next largest diameter bin. producer defined .06 .81 percent .01 11.48phi_0.00035mm Weight percent of sample with grain diameter greater than 11.48 phi, or 0.00035 mm and less than the floor of the next largest diameter bin. producer defined .01 .19 percent .01 12.02phi_0.000241mm Weight percent of sample with grain diameter greater than 12.02 phi, or 0.000241 mm and less than the floor of the next largest diameter bin. producer defined .00 .00 percent .01 13.02phi_0.00012mm Weight percent of sample with grain diameter greater than 13.02 phi, or 0.00012 mm and less than the floor of the next largest diameter bin. producer defined .00 .00 percent .01 Percent_Gravel Percent of sample greater than 2 mm producer defined .00 47.94 percent .01 Percent_Sand Percent of sample less than 2 mm and greater than 63 microns producer defined 1.70 80.26 percent .01 Percent_Silt Percent of sample less than 63 microns and greater than 4 microns producer defined 7.68 67.62 percent .01 Percent_Clay Percent of sample less than 4 microns producer defined 3.29 38.46 percent .01 Percent_Mud Percent of sample less than 63 microns producer defined 10.97 98.30 percent .01 Total_carbon_percent Average value of duplicate analyses of total carbon content (TC). The value -9999 indicates that data are not available. producer defined .17 25.42 weight percent .01 Total_organic_carbon_percent Average value of duplicate analyses of total organic carbon content (TOC). The value -9999 indicates that data are not available. producer defined .01 25.42 weight percent .01 Total_inorganic_carbon_percent Average value of duplicate analyses of total inorganic carbon content (TIC). The value -9999 indicates that data are not available. producer defined .00 1.66 weight percent .01 Calcium_carbonate_percent Calcium carbonate calculated as percent total inorganic carbon * 8.333. The value -9999 indicates that data are not available. producer defined .00 13.82 weight percent .01 Mean_Grain_Size_in_millimeter mean grain size in millimeter Producer defined 0.0061 1.1396 millimeter 0.0001 The data table is formatted in a single comma-separated values file Barter_Island_GrainSize_and_Carbon.csv. 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 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 Microsoft Excel 16.16.17 for Mac File contains table in .csv format No compression applied 0.02129 https://doi.org/10.5066/P14FZKEF Data and metadata can be downloaded using the Network_Resource_Name link. None. These data can be viewed with Microsoft Excel or any text reader. 20260424 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 Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998