Metadata: Identification_Information: Citation: Citation_Information: Originator: Julie C. Bernier Originator: Cheyenne S. Everhart Originator: Jennifer L. Miselis Publication_Date: 20250626 Title: Sedimentologic data and core descriptions from surface samples and sand augers collected in 2023 from the northern Chandeleur Islands, Louisiana Larger_Work_Citation: Citation_Information: Originator: Julie C. Bernier Originator: Cheyenne S. Everhart Originator: Jennifer L. Miselis Publication_Date: 20250626 Title: Sediment Data From Surface Samples and Sand Augers Collected in 2023 From the Northern Chandeleur Islands, Louisiana Series_Information: Series_Name: U.S. Geological Survey data release Issue_Identification: doi:10.5066/P13KRKA4 Publication_Information: Publication_Place: St. Petersburg, FL Publisher: U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center Online_Linkage: https://doi.org/10.5066/P13KRKA4 Description: Abstract: In 2023, scientists from the U.S. Geological Survey St. Petersburg Coastal and Marine Science Center (USGS SPCMSC) conducted a sediment sampling survey at the northern Chandeleur Islands, Louisiana. Funded by the Extending Government Funding and Delivering Emergency Assistance Act (Public Law 117-43) enacted on September 30, 2021, these data complement sediment data from samples previously collected from the Chandeleur Islands in 2007, 2008, 2012, 2013, and 2015. Purpose: This data release serves as an archive of sedimentologic data from surface samples and sand-auger cores collected from terrestrial and submerged barrier environments at the northern Chandeleur Islands, Louisiana from March 24-31, 2023 (USGS Field Activity Number [FAN] 2023-307-FA). Grain-size data from surface samples are provided to characterize the surficial sediment texture of back-barrier, island, and shoreface environments. Sedimentologic data from sand augers, including descriptive core logs and grain-size data, are provided to characterize the shallow subsurface stratigraphy at selected sites. Data acquisition and processing methods follow procedures described in Bernier and others (2014, 2023). Supplemental_Information: Data were collected during USGS FAN 2023-307-FA; two subFANs (23BIM03 and 23BIM04) were used to differentiate samples collected by separate field teams. Additional survey and data details are available from the U.S. Geological Survey Coastal and Marine Geoscience Data System (CMGDS) at https://cmgds.marine.usgs.gov/services/activity.php?fan=2023-307-FA. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20230324 Ending_Date: 20230331 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -88.91468 East_Bounding_Coordinate: -88.79994 North_Bounding_Coordinate: 30.06997 South_Bounding_Coordinate: 29.74132 Keywords: Theme: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:4e67da86-b79a-4666-984b-5fb89ee580c8 Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: geoscientificInformation Theme_Keyword: location Theme_Keyword: oceans Theme: Theme_Keyword_Thesaurus: USGS Thesaurus Theme_Keyword: geology Theme_Keyword: sedimentology Theme_Keyword: unconsolidated deposits Theme_Keyword: field sampling Theme_Keyword: drilling and coring Theme_Keyword: grain-size analysis Theme_Keyword: coastal processes Theme: Theme_Keyword_Thesaurus: Marine Realms Information Bank (MRIB) Keywords Theme_Keyword: coastal processes Theme_Keyword: stratigraphic characterization and correlation Theme_Keyword: sediment analysis Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: vibracore Theme_Keyword: sand auger Theme_Keyword: GRADISTAT Theme_Keyword: mean Theme_Keyword: sorting Theme_Keyword: skewness Theme_Keyword: kurtosis Theme_Keyword: Folk and Ward Theme_Keyword: U.S. Geological Survey Theme_Keyword: USGS Theme_Keyword: Coastal and Marine Hazards and Resources Program Theme_Keyword: CMHRP Theme_Keyword: St. Petersburg Coastal and Marine Science Center Theme_Keyword: SPCMSC Theme_Keyword: 2023-307-FA Place: Place_Keyword_Thesaurus: Common Geographic Areas (CGA) Place_Keyword: United States Place_Keyword: Louisiana Place_Keyword: Gulf of America Place: Place_Keyword_Thesaurus: Geographic Names Information System (GNIS) Place_Keyword: Chandeleur Islands Place: Place_Keyword_Thesaurus: None Place_Keyword: Gulf of Mexico Access_Constraints: No access constraints. Please see 'Distribution Information' for details. Use_Constraints: These data are marked with a Creative Common CC0 1.0 Universal License. These data are in the public domain and do not have any use constraints. Users are advised to read the dataset's metadata thoroughly to understand appropriate use and data limitations. Point_of_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center Contact_Person: Julie C. Bernier Contact_Position: Geologist Contact_Address: Address_Type: Mailing and Physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Contact_Voice_Telephone: 727-502-8000 Contact_Electronic_Mail_Address: jbernier@usgs.gov Data_Set_Credit: Funding and (or) support for this study were provided as part of the Extending Government Funding and Delivering Emergency Assistance Act (Public Law 117-43), enacted on September 30, 2021. The authors thank Nancy DeWitt, Andrew Farmer (USGS SPCMSC), and Erin Lyons (Cherokee Nation System Solutions contracted to USGS) for their assistance with data collection. This document was improved by scientific and metadata reviews by Noreen Buster (USGS SPCMSC) and Tess Rivenbark-Terrano (Cherokee Nation System Solutions contracted to USGS). Native_Data_Set_Environment: Environment as of Metadata Creation: Windows 11 Enterprise version 23H2 (22631.4890); Microsoft Excel for Microsoft 365 MSO (Version 2408 Build 16.0.17928.20538); National Geodetic Survey (NGS) Online Positioning User Service (OPUS); NovAtel GrafNav version 8.90.6611; Esri ArcGIS Pro version 3.3.2; Google Earth Pro version 7.3.6.10201; Rockware LogPlot 8 version 2022.1.31; GNU Image Manipulation Program (GIMP) version 2.10; IrfanView version 4.70; The Panorama Factory version 4.5; ImageJ version 1.54k; Adobe Illustrator 2025 version 29.3.1; Matlab version R2022A; Phil Harvey’s ExifTool (version 13.26). Cross_Reference: Citation_Information: Originator: Julie C. Bernier Originator: Cheyenne S. Everhart Originator: Daniel C. Ciarletta Originator: Jennifer L. Miselis Originator: Nancy T. DeWitt Publication_Date: 20230502 Title: Sediment data from vibracores and sand augers collected in 2021 and 2022 from Fire Island, New York Series_Information: Series_Name: U.S. Geological Survey data release Issue_Identification: doi:10.5066/P91P1T88 Publication_Information: Publication_Place: St. Petersburg, FL Publisher: U.S. Geological Survey Online_Linkage: https://doi.org/10.5066/P91P1T88 Cross_Reference: Citation_Information: Originator: Julie C. Bernier Originator: Kyle W. Kelso Originator: Noreen A. Buster Originator: James G. Flocks Originator: Jennifer L. Miselis Originator: Nancy T. DeWitt Publication_Date: 2014 Title: Sediment data collected in 2012 from the northern Chandeleur Islands, Louisiana Series_Information: Series_Name: U.S. Geological Survey Data Series Issue_Identification: 850 Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Online_Linkage: https://doi.org/10.3133/ds850 Cross_Reference: Citation_Information: Originator: Beckman Coulter Publication_Date: 201110 Title: LS 13 320 laser diffraction particle size analyzer Online_Linkage: https://www.beckmancoulter.com/wsrportal/techdocs?docname=B05577AB.pdf Cross_Reference: Citation_Information: Originator: Simon J. Blott Originator: Kenneth Pye Publication_Date: 20010928 Title: GRADISTAT: A grain size distribution and statistics package for the analysis of unconsolidated sediments Edition: Version 8.0 Series_Information: Series_Name: Earth Surface Processes and Landforms Issue_Identification: Volume 26, Issue 11 Other_Citation_Details: Pages 1237-1248 Online_Linkage: http://www.kpal.co.uk/gradistat.html Online_Linkage: https://doi.org/10.1002/esp.261 Cross_Reference: Citation_Information: Originator: OCM Partners Publication_Date: 2025 Title: 2022 USGS Topobathy Lidar: Breton Island, LA Online_Linkage: https://www.fisheries.noaa.gov/inport/item/73929 Cross_Reference: Citation_Information: Originator: Erin O. Lyons Originator: Chelsea A. Stalk Originator: Jennifer L. Miselis Originator: Noreen A. Buster Originator: Julie C. Bernier Originator: Nancy T. DeWitt Publication_Date: 20250325 Title: Coastal single-beam bathymetry data collected in 2023 from the Chandeleur Islands, Louisiana Series_Information: Series_Name: U.S. Geological Survey data release Issue_Identification: doi:10.5066/P1HJAVAR Publication_Information: Publication_Place: St. Petersburg, Florida Publisher: U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center Online_Linkage: https://doi.org/10.5066/P1HJAVAR Cross_Reference: Citation_Information: Originator: Chelsea A. Stalk Originator: Christopher C. Bemelmans Originator: Jennifer L. Miselis Publication_Date: 20250325 Title: Coastal bathymetry and backscatter data collected June-August 2023 from the Chandeleur Islands, Louisiana Series_Information: Series_Name: U.S. Geological Survey data release Issue_Identification: doi:10.5066/P1NWHXZS Publication_Information: Publication_Place: St. Petersburg, Florida Publisher: U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center Online_Linkage: https://doi.org/10.5066/P1NWHXZS Cross_Reference: Citation_Information: Originator: Robert L. Folk Originator: William C. Ward Publication_Date: 19570301 Title: Brazos River bar: A study in the significance of grain size parameters Series_Information: Series_Name: Journal of Sedimentary Petrology Issue_Identification: Volume 27, No. 1 Other_Citation_Details: Pages 3-26 Online_Linkage: https://doi.org/10.1306/74D70646-2B21-11D7-8648000102C1865D Cross_Reference: Citation_Information: Originator: William C. Krumbein Publication_Date: 19340801 Title: Size frequency distributions of sediments Series_Information: Series_Name: Journal of Sedimentary Petrology Issue_Identification: Volume 4, No. 2 Other_Citation_Details: Pages 65-77 Online_Linkage: https://doi.org/10.1306/D4268EB9-2B26-11D7-8648000102C1865D Cross_Reference: Citation_Information: Originator: Chester K. Wentworth Publication_Date: 1922 Title: A scale of grade and class terms for clastic sediments Series_Information: Series_Name: Journal of Geology Issue_Identification: Volume 30, No. 5 Other_Citation_Details: Pages 377-392 Online_Linkage: https://www.jstor.org/stable/30063207 Cross_Reference: Citation_Information: Originator: Robert L. Folk Publication_Date: 195407 Title: The distinction between grain size and mineral composition in sedimentary-rock nomenclature Series_Information: Series_Name: Journal of Geology Issue_Identification: Volume 62, No. 4 Other_Citation_Details: Pages 344-359 Online_Linkage: https://doi.org/10.1086/626171 Cross_Reference: Citation_Information: Originator: Christopher Bronk Ramsey Publication_Date: 2009 Title: Bayesian analysis of radiocarbon dates Series_Information: Series_Name: Radiocarbon Issue_Identification: Volume 51, Issue 1 Other_Citation_Details: Pages 337-360 Online_Linkage: https://doi.org/10.1017/S0033822200033865 Cross_Reference: Citation_Information: Originator: Paula J. Reimer Originator: and others Publication_Date: 20200812 Title: The IntCal20 northern hemisphere radiocarbon age calibration curve (0–55 cal kBP) Series_Information: Series_Name: Radiocarbon Issue_Identification: Volume 62, Issue 4 Other_Citation_Details: Pages 725-757 Online_Linkage: https://doi.org/10.1017/RDC.2020.41 Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: The positional accuracy of the sample locations is determined by the method of coordinate derivation: (a) Differential Global Positioning System (DGPS) coordinates obtained by post-processing raw position data recorded at time of collection using NGS OPUS and NovAtel GrafNav software packages or (b) GPS coordinates recorded at time of collection using a handheld or boat-mounted GPS. Due to the assumption of grain sphericity of the Fraunhofer optical model used by the Coulter LS13 320 particle-size analyzer (PSA) for grain-size analysis, angular particles are measured by their longest axis (Beckman Coulter, 2011). When enough thin, angular material is present, the LS13 320 output files often report a percentage of the grain size distribution within the 1-2 millimeter (mm) fraction, despite all samples being sieved at 1 mm before analysis. The grain-size data represent the sample averages for a subset of the statistical parameters calculated by GRADISTAT (Blott and Pye, 2001). The number of runs included in the averaged results are reported, and the standard deviation of the averaged results are reported for most parameters. A secondary data review determined that all grain-size data reported met the laboratory’s quality control requirements. Beckman Coulter control standards G15 (15 microns [µm]) and GB500 (500 µm) were analyzed on the Coulter LS13 320 particle-size analyzer before all sediment samples were analyzed to validate instrument performance (Beckman Coulter, 2011). In addition to processing the samples submitted for radiocarbon dating, Beta Analytic, Inc. also analyzes known-value reference materials. All quality assurance measurements passed the internal acceptance tests. Logical_Consistency_Report: Position and elevation data at each core site and selected surface sample sites were recorded with a Spectra Precision SP80 DGPS receiver and geodetic antenna. DGPS data were recorded concurrently throughout the survey at a nearby base station using a Spectra Precision SP90M DGPS receiver and Trimble Zephyr-3 Base antenna. The average baseline distance for DGPS sites was 7.0 +/- 4.9 kilometers (km) (1-sigma) and the maximum baseline distance was 20.6 km. Position data at the remaining sample sites were recorded at the time of collection using a Garmin GPSMap 79SC handheld GPS or Garmin Echomap UHD 64cv boat-mounted GPS, and sample elevations were subsequently interpolated from temporally similar lidar (OCM Partners, 2025), single-beam echosounder (SBES; Lyons and others, 2025) or multibeam echosounder (MBES, Stalk and others, 2025) datasets. Grain-size sample runs in the GRADISTAT output files for which the mean Folk and Ward (1957) grain-size varied from the set average by more than 1.5 standard deviations were not included in final averaged results. Completeness_Report: Dataset is considered complete for the information presented. Data release doi:10.5066/P13KRKA4 includes the geographic locations; site elevations; core descriptions, core photos, and core x-rays (when applicable); and grain-size data from 10 sand-auger cores and 190 surface samples collected from the northern Chandeleur Islands, Louisiana, March 24-31, 2023 (USGS FAN 2023-307-FA). Radiocarbon ages for the plant material and organic sediment fractions for 2 samples from core 23BIM03-20 are also provided. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: Position and elevation associated with each DGPS site was determined by post-processed differential correction of the base/rover setup using NovAtel's GrafNav software. The base station used for control during this survey, stamped MRK3, was installed by the USGS in 2015 at the northern Chandeleur Islands east of Schooner Harbor and is not in the NGS database with an associated Permanent Identifier (PID). The coordinate values of the MRK3 were derived from the time-weighted average of session values obtained from NGS OPUS. The estimated horizontal accuracy (2-sigma) of the post-processed base coordinates for MRK3 is +/- 0.00017 degrees latitude and +/- 0.00017 degrees longitude. Differential processing of the full-carrier phase data in GrafNav allows precise positioning of the base and rover receivers and improves the rover positions by assessing positional errors computed at the base receiver and applying those errors or differences to the rover receiver. Forward and backward time-series processing of the rover data provides an independent calculation of the baseline trajectory and rover position relative to the base station; the positional accuracy can be estimated by differencing the time series (position separation). The estimated post-processed horizontal accuracy (2-sigma) for all rover data to the MRK3 base station was 0.007 +/- 0.005 meters (m). For samples locations recorded using a Garmin GPSMap 79SC handheld GPS or Garmin Echomap UHD 64cv boat-mounted GPS, the manufacturer's specified accuracy is 3 to 5 meters (95% typical). Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: As described above, position and elevation associated with each DGPS site was determined by post-processed differential correction. The estimated vertical accuracy (2-sigma) of the post-processed base coordinates for MRK3 is +/- 0.012 m. The estimated post-processed vertical accuracy (2-sigma) for all rover data to the MRK3 base station was 0.012 +/- 0.009 m. For samples locations recorded using a Garmin GPSMap 79SC handheld GPS or Garmin Echomap UHD 64cv boat-mounted GPS, the vertical accuracy is dependent on the vertical accuracy of the source lidar, SBES, and MBES elevation data (OCM Partners, 2025; Lyons and others, 2025; Stalk and others, 2025). Lineage: Process_Step: Process_Description: Sample collection- Sand augers were collected using an AMS, Inc. sand/loose sediment soil probe, which can accommodate a 2.54 centimeter (cm) (1 inch) diameter by approximately 96 cm (3 feet) plastic sleeve. After extraction, each core was capped, sealed, and labeled with the core number and orientation. All cores were transported to the SPCMSC sediment laboratory for processing and analysis. Surface samples were collected using (a) a scoop for samples collected on the emergent island or shallow intertidal areas or (b) a WILDCO Petit Ponar grab sampler deployed from a skiff or boat for submerged samples collected from water depths greater than about 1 m. Position and elevation data at each sand auger site and selected surface sample sites were recorded using a Spectra Precision SP80 DGPS receiver and geodetic antenna recording full-carrier-phase positioning signals from satellites at a rate of 1 second (s). Raw data were recorded for a minimum of 5 minutes. DGPS data were recorded concurrently throughout the survey at a nearby base station established at MRK3 using a Spectra Precision SP90M DGPS receiver and Trimble Zephyr-3 Base antenna. Position data at the remaining sample sites were recorded at the time of collection using a Garmin GPSMap 79SC handheld GPS or Garmin Echomap UHD 64cv boat-mounted GPS. Process_Date: 2023 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Julie C. Bernier Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical address Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Contact_Voice_Telephone: (727) 502-8000 Contact_Electronic_Mail_Address: jbernier@usgs.gov Process_Step: Process_Description: Navigation Processing- Base station data were post-processed through the NGS OPUS and the time-weighted coordinates calculated from all base-station occupations at MRK3 were used for post-processing. The base station coordinates were imported into GrafNav and, for DGPS sites, the data from the rover GPS were post-processed to the concurrent base-station session data. The final, differentially corrected, GPS positions for each rover session were processed and exported in the North American Datum of 1983 (NAD83) (2011) coordinate system and processed orthometric elevations are reported relative to the North American Vertical Datum of 1988 (NAVD88), derived using the GEOID18 geodetic model. For samples locations recorded using a Garmin GPSMap 79SC handheld GPS or Garmin Echomap UHD 64cv boat-mounted GPS, sample elevations were subsequently interpolated from lidar data collected in October 2022 (OCM Partners, 2025) or SBES and MBES data collected in June and August, 2023 (Lyons and others, 2025; Stalk and others, 2025). Process_Date: 2024 Source_Produced_Citation_Abbreviation: 2023-307-FA_SampleSites.zip Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Julie C. Bernier Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical address Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Contact_Voice_Telephone: (727) 502-8000 Contact_Electronic_Mail_Address: jbernier@usgs.gov Process_Step: Process_Description: Sand auger processing- At the SPCMSC sediment laboratory, each sand auger section was split lengthwise, photographed, x-rayed, described macroscopically using standard sediment-logging methods, and subsampled for grain-size analysis. The split sand augers were photographed in approximately 30-cm overlapping segments with a Nikon D3500 digital camera with an 18- to 55-mm zoom lens using consistent (manually programmed) settings with autofocus from a fixed height. The raw images were white-balanced using GIMP software, cropped to the same extent (to remove areas outside of the core barrel), and "stitched" together using The Panorama Factory software, providing seamless high-resolution whole-core images exported as Joint Photographic Experts Group (JPEG) format. Core x-rays were acquired using an Ecotron EPX-2800 x-ray unit at 85 kilovolts for 16 milliampere-seconds from a height of 79 cm. Each x-radiograph was captured on an 11 × 14-inch phosphor cassette, which was scanned on an iCRco, Inc., iCR3600+ scanner at 254 pixels per inch and exported as a 16-bit Tagged Image File Format (TIF) image. The raw x-radiographs show a slight anode heel effect, which is a variation in x-ray intensity along the anode-cathode axis that results in non-uniform pixel intensity across the image. This effect was corrected by subtracting a background pixel intensity template from each raw image (Bernier and others, 2014). The images were cropped (to the same extent and to remove areas outside of the cassette), background image subtracted, and grayscale color inversion was applied using ImageJ software. Depending on core length, sand augers that did not fit onto the phosphor cassette were x-rayed in "top" and "bottom" or "top," "middle," and "bottom" segments and then merged in Adobe Illustrator. Textural descriptions for the core logs are based on macroscopic observations. Sediment color is based on the Munsell soil color system (https://munsell.com/color-products/color-communications-products/environmental-color-communication/munsell-soil-color-charts/). Descriptive core logs were compiled using Rockware LogPlot software. Samples consisted of 3-cm sections sampled at varying intervals down-core based on observed sedimentologic changes. Two samples from core 23BIM03-20 collected for radiocarbon dating and were sealed, labeled, and shipped to Beta Analytic, Inc. for analysis. Process_Date: 2024 Source_Produced_Citation_Abbreviation: 2023-307-FA_CorePhotos.zip Source_Produced_Citation_Abbreviation: 2023-307-FA_CoreXRays.zip Source_Produced_Citation_Abbreviation: 2023-307-FA_CoreLogs.zip Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Julie C. Bernier Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical address Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Contact_Voice_Telephone: (727) 502-8000 Contact_Electronic_Mail_Address: jbernier@usgs.gov Process_Step: Process_Description: Grain-size PSA analysis- At the SPCMSC sediment laboratory, grain-size analyses were performed using a Coulter LS13 320 (https://www.beckmancoulter.com/) PSA. The LS13 320 uses laser diffraction to measure the size distribution of sediments from 0.4 µm to 2 mm, encompassing clay to very coarse-grained sand. To prevent large shell fragments from damaging the instrument, particles greater than 1 mm in diameter (coarse sand) were separated from all samples prior to analysis using a number 18 (1 mm) U.S. standard sieve, which meets the American Society for Testing and Materials (ASTM) E11 standard specifications for determining particle size using woven-wire test sieves. Prior to processing through the LS13 320, samples with visually observed organic content were digested in 30% hydrogen peroxide (H2O2) to remove excess organic material; six samples were analyzed both undigested and digested for comparison. Following SPCMSC standard procedures, samples were (a) dried at 60 degrees Celsius and dry loaded into the LS13 320 (well-sorted sandy sediment) or (b) homogenized in water and sonicated to suspend in solution prior to transferring to the LS13 320 (sediment with visually observed mud content or samples that were previously digested with H2O2). Two subsamples from each sample were processed through the instrument a minimum of four runs each. Once introduced into the LS13 320, the sediment in the sample well was sonicated with a sonicator wand for 30 to 60 seconds to separate any aggregates before starting the first run for both subsamples. The LS13 320 measures the particle-size distribution of each sample by passing sediment suspended in solution between two narrow panes of glass in front of a laser. Light is scattered by the particles into characteristic refraction patterns measured by an array of photodetectors as intensity per unit area and recorded as relative volume for 92 size-related channels (bins). Process_Date: 2024 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Julie C. Bernier Contact_Organization: U.S. Geological Survey Contact_Position: Physical Scientist Contact_Address: Address_Type: mailing and physical address Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Contact_Voice_Telephone: (727) 502-8000 Contact_Electronic_Mail_Address: jbernier@usgs.gov Process_Step: Process_Description: Grain-size processing- For samples that were dry loaded into the LS13 320, sediment >1 mm in diameter was reported as a percent fraction of the total bulk dry weight of each sample (bulk dry weights were not measured for samples loaded in solution). The raw PSA grain-size data were run through the free software GRADISTAT version 9, (Blott and Pye, 2001; kpal.co.uk/gradistat), which calculates the mean, sorting, skewness and kurtosis of each sample geometrically, in metric units, and logarithmically, in phi (Φ) units (Krumbein, 1934), using the Folk and Ward (1957) scale. GRADISTAT also reports the descriptive sediment texture after Folk (1954) and calculates the fraction of sediment from each sample by size category (for example, clay, coarse silt, fine sand) based on a modified Wentworth (1922) size scale. A macro function in Microsoft Excel, developed by the USGS SPCMSC, was applied to the data to calculate average and standard deviation for each sample set (8 runs per sample), and highlight runs that varied from the set average by more than ±1.5 standard deviations. The highlighted runs were removed from the results and the sample average was recalculated using the remaining runs. The averaged results for all samples and the number of averaged runs are included in an Excel workbook, organized by subFAN, and comma-separated values (.csv) data files, organized by sample type (core or surface sample). The raw LS13 320 output files, which list the class weight retained in each aperture bin as a percent of the total sample weight for each sample run, were compiled by GRADISTAT, imported into Matlab, and averaged for each sample (8 runs per sample except for samples with runs flagged and removed as described above); those grain-size distribution data are also included in this data release for advanced users. Process_Date: 2024 Source_Produced_Citation_Abbreviation: 2023-307-FA_GrainSize_SumStats.xlsx Source_Produced_Citation_Abbreviation: 2023-307-FA_Cores_GrainSize_SumStats.csv Source_Produced_Citation_Abbreviation: 2023-307-FA_Surface_GrainSize_SumStats.csv Source_Produced_Citation_Abbreviation: 2023-307-FA_GrainSizeDistributions.xlsx Source_Produced_Citation_Abbreviation: 2023-307-FA_Cores_GrainSizeDistributions.csv Source_Produced_Citation_Abbreviation: 2023-307-FA_Surface_GrainSizeDistributions.csv Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Julie C. Bernier Contact_Organization: U.S. Geological Survey Contact_Position: Physical Scientist Contact_Address: Address_Type: mailing and physical address Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Contact_Voice_Telephone: (727) 502-8000 Contact_Electronic_Mail_Address: jbernier@usgs.gov Process_Step: Process_Description: Grain-size plots- The down-core grain-size distributions (>1 mm fraction, coarse sand, medium sand, fine sand, very fine sand, and mud classes) for each sand auger were plotted in Matlab and exported as a JPEG image; cores are arranged from north (top) to south (bottom) of image. The sediment texture for all samples were also plotted in Matlab on a ternary diagram using the Folk (1954) fine sediment classification and exported as a JPEG image. Process_Date: 2025 Source_Produced_Citation_Abbreviation: 2023-307-FA_Cores_GrainSizeDistributions.jpg Source_Produced_Citation_Abbreviation: 2023-307-FA_GrainSize_TernaryPlot.jpg Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Julie C. Bernier Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical address Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Contact_Voice_Telephone: (727) 502-8000 Contact_Electronic_Mail_Address: jbernier@usgs.gov Process_Step: Process_Description: Radiocarbon dating- Both the organic sediment fraction and plant material from two organic-rich subsamples from core 23BIM03-20 were analyzed using accelerated mass spectrometry (AMS) radiocarbon (14C) dating at Beta Analytic, Inc. (Miami, Florida). For each sample, the conventional 14C radiocarbon age as well as calibrated age ranges are reported. Calibrated ages are based on terrestrial calibration curves from INTCAL20 (Reimer and others, 2020) using the High Probability Density (HPD) Range Method (Bronk Ramsey, 2009). For additional information on understanding calibrated radiocarbon ages, refer to the Beta Analytic, Inc. (https://www.radiocarbon.com/calendar-calibration-carbon-dating.htm) or University of Oxford Radiocarbon Accelerator Unit (https://c14.arch.ox.ac.uk/calibration.html, https://c14.arch.ox.ac.uk/explanation.php) websites. Process_Date: 2023 Source_Produced_Citation_Abbreviation: 23BIM03-20_14CData.xlsx Source_Produced_Citation_Abbreviation: 23BIM03-20_14CData.csv Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Beta Analytic, Inc. Contact_Organization: Beta Analytic, Inc. Contact_Address: Address_Type: mailing and physical address Address: 4985 SW 74th Court City: Miami State_or_Province: FL Postal_Code: 33155 Contact_Voice_Telephone: (305) 667-5167 Contact_Electronic_Mail_Address: lab@radiocarbon.com Process_Step: Process_Description: Populating image headers- Credit, contact information, copyright, usage terms, image descriptions, attribution url, metadata link, and georeferencing information were added to the exchangeable image file format (EXIF) header of each image using Phil Harvey’s ExifTool. The images were grouped by image type (core logs, photographs, and x-rays) into separate folders: 2023-307-FA_CoreLogs, 2023-307-FA_CorePhotos, and 2023-307-FA_CoreXRays. All information in the scripts were the same among all images, aside from the EXIF:ImageDescription, EXIF:DateTimeOriginal, EXIF:GPSLatitude and EXIF:GPSLongtitude information, as that information varies for each core. A separate script containing the core-specific header information was run on each image individually to populate those headers. The core logs and photographs are published as JPGs, whereas the core x-rays are published as TIFs. Therefore, all mentions of the file extension in the example scripts below used ".TIF" rather than ".JPG" for the x-ray images. Image header information was also populated for the files 2023-307-FA_Cores_GrainSizeDistributions.jpg and 2023-307-FA_GrainSize_TernaryPlot.jpg in 2023-307-FA_GrainSizeData.zip. However, since these image details grain-size data for all samples, the EXIF:GPSMapDatum, EXIF:GPSAreaInformation, and core-specific headers were not added. First, the following command was run on all images in a folder to preserve filenames: exiftool -P "-XMP:PreservedFileName1 mm fraction was not measured are denoted with a (-). For full entity and attribute details, please refer to the accompanying data dictionary, 2023-307-FA_GrainSize_DataDictionary.docx, included in the file 2023-307-FA_GrainSizeData.zip. 2023-307-FA_GrainSize_SumStats.xlsx contains a copy of the data dictionary as well as the summary LS13 320 data organized by sample type and subFAN. Entity_Type_Definition_Source: USGS Detailed_Description: Entity_Type: Entity_Type_Label: 2023-307-FA_GrainSizeDistributions.xlsx, 2023-307-FA_Cores_GrainSizeDistributions.csv, 2023-307-FA_Surface_GrainSizeDistributions.csv Entity_Type_Definition: Grain-size distribution data for each sample listing the class weight retained in each aperture bin as a percent of the total sample weight. Results are the average of 8 runs per sample for most samples. Files are provided in Microsoft Excel (.xlsx) and comma-separated values (.csv) formats. Entity_Type_Definition_Source: USGS Attribute: Attribute_Label: Aperture_microns Attribute_Definition: Coulter software bin aperture, in microns Attribute_Definition_Source: Beckman Coulter LS13 320 Software Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0.375 Range_Domain_Maximum: 2000 Attribute: Attribute_Label: MedianDiameter_microns Attribute_Definition: Median of Coulter software bin aperture, in microns Attribute_Definition_Source: Beckman Coulter LS13 320 Software Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0.3935 Range_Domain_Maximum: 1911 Detailed_Description: Entity_Type: Entity_Type_Label: 23BIM03-20_14CData.xlsx, 23BIM03-20_14CData.csv Entity_Type_Definition: File containing the results of radiocarbon analyses for 2023-307-FA sand auger 23BIM03-20 subsamples. For full entity and attribute details, please refer to the accompanying data dictionary, 23BIM03-20_14C_DataDictionary.docx, included in the file 23BIM03-20_14CData.zip. Files are provided in Microsoft Excel (.xlsx) and comma-separated values (.csv) formats. Entity_Type_Definition_Source: USGS, Beta Analytic, Inc. Overview_Description: Entity_and_Attribute_Overview: The detailed attribute descriptions for the grain-size summary statistics and the radiocarbon analyses are provided in the data dictionaries 2023-307-FA_GrainSize_DataDictionary.docx and 23BIM03-20_14CDataDictionary.docx included in the files 2023-307-FA_GrainSizeData.zip and 23BIM03-20_14CData.zip, respectively. These metadata are not complete without these files. Entity_and_Attribute_Detail_Citation: Entity and attribute information was generated by the individual and/or agency identified as the originator of the dataset. Please review the rest of the metadata record for additional details and information. Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center Contact_Person: USGS SPCMSC Data Management Contact_Address: Address_Type: Mailing and Physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: United States Contact_Voice_Telephone: 727-502-8000 Contact_Electronic_Mail_Address: gs-g-spcmsc_data_inquiries@usgs.gov Distribution_Liability: 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 for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: comma-delimited text, JPEG, KML, Microsoft Excel format, Microsoft Word format, shapefile, TIFF Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: https://coastal.er.usgs.gov/data-release/doi-P13KRKA4/data/2023-307-FA_SampleSites.zip Network_Resource_Name: https://coastal.er.usgs.gov/data-release/doi-P13KRKA4/data/2023-307-FA_CoreLogs.zip Network_Resource_Name: https://coastal.er.usgs.gov/data-release/doi-P13KRKA4/data/2023-307-FA_CorePhotos.zip Network_Resource_Name: https://coastal.er.usgs.gov/data-release/doi-P13KRKA4/data/2023-307-FA_CoreXRays.zip Network_Resource_Name: https://coastal.er.usgs.gov/data-release/doi-P13KRKA4/data/2023-307-FA_GrainSizeData.zip Network_Resource_Name: https://coastal.er.usgs.gov/data-release/doi-P13KRKA4/data/23BIM03-20_14CData.zip Fees: None. No fees are applicable for obtaining the dataset. Technical_Prerequisites: All spreadsheets were created in Microsoft Excel; these data are also provided as comma-separated values (.csv) text files. Core locations are also provided as GIS data files in Esri shapefile (.shp) and Keyhole Markup Language (KML) formats; these files can be opened using the free Google Earth (https://www.google.com/earth/) GIS viewer. Core logs, core photos, and grain-size distribution plots are provided in Joint Photographic Experts Group (JPEG) format and core x-rays are provided in Tagged Image File Format (TIFF) format. Image metadata (exif image headers) for the JPEG and TIFF images can be read using Phil Harvey’s ExifTool (https://exiftool.org/). Metadata_Reference_Information: Metadata_Date: 20250626 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center Contact_Person: USGS SPCMSC Data Management Contact_Address: Address_Type: Mailing and Physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: United States Contact_Voice_Telephone: 727-502-8000 Contact_Electronic_Mail_Address: gs-g-spcmsc_data_inquiries@usgs.gov Metadata_Standard_Name: Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998