Nancy T. DeWitt James G. Flocks Julie C. Bernier 20260423 tabular and vector digital data Nancy T. DeWitt James G. Flocks Julie C. Bernier 20260423 U.S. Geological Survey data release doi:10.5066/P14M8EZU St. Petersburg, Florida U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center https://doi.org/10.5066/P14M8EZU As part of the restoration monitoring component of the Deepwater Horizon early restoration project, scientists from the U.S. Geological Survey St. Petersburg Coastal and Marine Science Center (USGS SPCMSC) conducted single-beam and multibeam bathymetry surveys around Breton Island, Louisiana (LA), from August 5-10, 2024, for Field Activity Number (FAN) 2024-320-FA. The purpose of data collection was to measure submerged elevations and develop a digital elevation model of the seafloor around Breton Island. These data were collected as part of the Louisiana Outer Coast Restoration Construction Monitoring project supported by funding from the Natural Resource Damage Assessment - Deepwater Horizon Restoration Activities and, in combination with both previous and planned future surveys, can be used to evaluate elevation change following island restoration. The survey area covered approximately 77 square kilometers (km^2) of nearshore environment surrounding Breton Island and extended into the adjacent portion of the former Mississippi River to Gulf Outlet (MRGO). The single-beam bathymetry was acquired using two 12-foot personal watercraft (PWC) and one 20-foot power catamaran. All vessels were outfitted with high precision Global Navigation Satellite System (GNSS) receivers, motion reference units, and survey grade single-beam echosounders (SBES). For additional information on post-processing steps, please refer to DeWitt and others (2016) and Hansen and others (2017). Multibeam echosounder (MBES) data including the backscatter component and chirp seismic sub-bottom data were collected concurrently as part of FAN 2024-320-FA; those data are available as separate data releases: Bemelmans and others (2025); Forde and others (2025), respectively. To conduct a nearshore single-beam bathymetry survey during the summer of 2024 that replicated coastal single-beam bathymetry data collected in 2022 from Breton Island, Louisiana (Lyons and others, 2024). Single-beam data and associated files were collected during USGS Field Activity Number (FAN) 2024-320-FA. Vessel specific single-beam bathymetry echosounder data (SBES) were assigned subFANs; 24BIM07 (Research Vessel [R/V] G. Hill - TVEE), 24BIM08 (R/V Shark - WVR1) and 24BIM09 (R/V Chum - WVR2). The x,y,z data are provided in American Standard Code for Information Interchange (ASCII) text format as: (1) World Geodetic System 1984 (WGS84) realization G2139, Universal Transverse Mercator (UTM) Zone 16 North (N) for the horizontal and WGS84 (G2139) ellipsoidal height in meters (m) for the vertical; and (2) North American Datum of 1983 (NAD83) realization 2011 for the horizontal, and North American Vertical Datum 1988 (NAVD88) orthometric height in meters with respect to GEOID18 for the vertical. These data should not be used for navigational purposes. Additional survey and data details are available from the USGS Coastal and Marine Geoscience Data System (CMGDS) at, https://cmgds.marine.usgs.gov/services/activity.php?fan=2024-320-FA. 20240806 20240810 ground condition Complete None planned -89.2387412 -89.0932354 29.5359716 29.4217234 USGS Metadata Identifier USGS:9e25e5cd-47a8-4f68-a585-16879e9b7ad4 ISO 19115 Topic Category geoscientificInformation elevation oceans location imageryBaseMapsEarthCover Global Change Master Directory EARTH SCIENCE > OCEANS > BATHYMETRY/SEAFLOOR TOPOGRAPHY > BATHYMETRY > COASTAL BATHYMETRY GOVERNMENT AGENCIES-U.S. FEDERAL AGENCIES > DOI > USGS DOI/USGS/CMG/SP> ST. PETERSBURG COASTAL AND MARINE SCIENCE CENTER, COASTAL AND MARINE GEOLOGY, U.S. GEOLOGICAL SURVEY, U.S. DEPARTMENT OF THE INTERIOR USGS Thesaurus marine geology geophysics bathymetry single-beam echo sounder ocean characteristics ocean processes geospatial datasets None U.S. Geological Survey hydrography trackline single-beam bathymetry Common Geographic Areas Louisiana United States Breton Islands Breton Sound Gulf of America None Breton Island, Louisiana Gulf of Mexico Mississippi River to Gulf Outlet None 2024 No access constraints. Please see 'Distribution Information' for details. These data are marked with a Creative Common CC0 1.0 Universal License. Nancy T. DeWitt U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center Geologist mailing and physical address

600 4th Street South

St. Petersburg FL 33701-4846 USA 727-502-8000 ndewitt@usgs.gov Funding and (or) support for this study was provided as part of the restoration monitoring component of the Deepwater Horizon early restoration project. The authors would like to thank members of the USGS SPCMSC Operations staff specifically Billy J. Reynolds, Benjamin A. Galbraith, Christopher C. Bemelmans, and Maxwell O. Reynolds for their field acquisition support. This document was improved by scientific/editorial and metadata reviews from Andrew S. Farmer, Jennifer L. Miselis, and Breanna N. Williams of the SPCMSC. Environment as of Metadata Creation: Microsoft Windows 11 Enterprise Version 23H2 (Build 22631.4317); RINEX Converter version 5.1.0; National Oceanic and Atmospheric Administration (NOAA) National Geodetic Survey (NGS) Online Positioning User Service (OPUS) (https://geodesy.noaa.gov/OPUS/); Horizontal Time-Dependent Positioning (HTDP) online transformation utility version 3.5.0 (https://www.ngs.noaa.gov/TOOLS/Htdp/Htdp.shtml); NovAtel's Waypoint software GrafNav version 9.00.2207; HYPACK® A Xylem Brand version 22.3.4.0; Environmental Systems Research Institute (Esri) ArcGIS Pro version 3.3.2; NOAA NGS VDatum software version 4.7.1 (https://vdatum.noaa.gov/). Erin O. Lyons Nancy T. DeWitt James G. Flocks Billy J. Reynolds Andrew S. Farmer Julie C. Bernier Benjamin A. Galbraith Chelsea A. Stalk Natasha J. Nieckoski Maxwell O. Reynolds 20240220 U.S. Geological Survey data release doi:10.5066/P97NH83J St. Petersburg, Florida U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center https://doi.org/10.5066/P97NH83J Arnell S. Forde Chelsea A. Stalk James G. Flocks 20250312 U.S. Geological Survey data release doi:10.5066/P13SMFT7 St. Petersburg, Florida U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center https://doi.org/10.5066/P13SMFT7 Christopher C. Bemelmans Chelsea A. Stalk James G. Flocks 20250402 U.S. Geological Survey data release doi:10.5066/P13BWAJC St. Petersburg, Florida U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center https://doi.org/10.5066/P13BWAJC NovAtel 202307 Alberta, Canada Novatel Inc. https://hexagondownloads.blob.core.windows.net/public/Novatel/assets/Documents/Manuals/Waypoint-Software-User-Manual-OM-20000166/Waypoint_9.00_Software_User_Manual.pdf Xylem 2023 Middletown, CT A Xylem brand https://www.xylem.com/siteassets/brand/hypack/resources/manual/2023-hypack-user-manual.pdf Nancy T. DeWitt Joseph J. Fredericks James G. Flocks Jennifer L. Miselis Stanley D. Locker Jack L. Kindinger Julie C. Bernier Kyle W. Kelso Billy J. Reynolds Dana S. Wiese Trevor N. Browning 20160801 U.S. Geological Survey Data Series 1005 Reston, VA U.S. Geological Survey https://doi.org/10.3133/ds1005 Mark E. Hansen Nancy T. Dewitt Billy J. Reynolds 20170810 U.S. Geological Survey Data Series 1031 Reston, VA U.S. Geological Survey https://doi.org/10.3133/ds1031 This dataset is derived from one survey using three vessels with identical equipment systems and acquisition settings. Prior to deployment, each vessel's equipment offsets were surveyed in using a Spectra Precision Geodimeter total station. Offsets between the single-beam transducers, motion reference unit, and the antenna reference point (ARP) were precisely measured with respect to the vessels frame of reference. During mobilization, the offset measurements were field checked and verified against the total station measurements. Total station offsets were then digitally entered into the acquisition and (or) processing software. Methods were employed to maintain data collection consistency aboard the vessels. Differential Global Positioning System (DGPS) base station coordinates were obtained by post-processing through NOAA NGS OPUS. Roving vessels remained within < 10-km of the bases station. The navigation positioning data were post processed using NovAtel 's Waypoint Software GrafNav. For more information on the dataset's accuracy, see the 'Quality Control, Quality Assurance (QA/QC) and Uncertainty Analysis' process step below. These data were collected during one survey with consistent instrument calibrations and consistent acquisition methods. This data release contains single-beam bathymetry data points (x,y,z) collected in August 2024 around Breton Island, Louisiana. The horizontal positions and vertical elevations are provided in two datums, 1) WGS84 (G2139) and ellipsoid height, and 2) NAD83(2011) NAVD88 UTM 16N GEOID18. These datasets are considered complete. Users are advised to read the complete metadata record carefully for additional details. The USGS-SPCMSC benchmark BRET, installed in 2007 on Breton Island for USGS data acquisition and processing, was used for local control. The maximum horizontal surface vector distance from the base station to all three roving vessels was 8.34 km. The coordinate values of the GNSS base station BRET are the time-weighted average of values obtained from NOAA NGS OPUS for all occupations during the surveys in 2022 (Lyons and others, 2024). The estimated horizontal accuracy (2-sigma) of the post-processed base coordinates for BRET is +/- 0.00024 seconds latitude and +/- 0.00013 seconds longitude. Horizontal positional accuracy associated with each data point was determined by post-processed differential correction of the base/rover GNSS sessions using GrafNav. Processing the full-carrier phase data allows precise positioning of the base and rover receivers. Differential processing 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 kinematic (rover) data provides an independent combined smoothed-trajectory solution of the baseline between the rover position and the base station. The positional accuracy can be estimated by differencing the time series (position separation). The averaged post-processed standard deviation horizontal accuracy (2-sigma) for all kinematic rover data processed to the BRET benchmark was 0.008 +/- 0.005 meters (m). As described in the horizontal position accuracy report, coordinate values for BRET base station were the time-weighted average of values from the NOAA NGS OPUS. The averaged vertical accuracy (2-sigma) of the post-processed base coordinates for BRET are +/- 0.012 m. The vertical position accuracy associated with each data point were determined by post-processed differential correction of the base/rover GNSS sessions using GrafNav. The average post-processed standard deviation vertical accuracy (2-sigma) for all kinematic rover data processed to the BRET benchmark was 0.015 +/- 0.010 m. GNSS Acquisition: BRET benchmark located on Breton Island, Louisiana was used for local navigation control. It was equipped with a Spectra Precision SP90M GNSS receiver with a Trimble Zephyr 3 Base GNSS antenna recording full-carrier-phase positioning signals from satellites at a rate of 0.1 second (s) (equal to 10 hertz [Hz]). The same GNSS receivers were used on the rovers, except the GNSS antennas varied by vessel (TVEE - Trimble® Zephyr 3 Rover; WVR1/WVR2 - Spectra Precision® SPGA Rover). The base station GNSS data files were converted from Spectra Precision proprietary G-file formats (e.g. GBRETA24.218) into the non-proprietary Receiver Independent Exchange Format (RINEX [https://igs.org/wg/Rinex/]) version 2.11 (e.g. BRET218A.24O) for submission to NOAA NGS OPUS. In preparation for post processing at a later step, using the RINEX converter again, both the base and rover G-files were converted into RINEX version 3.04 (e.g. TVEE00000_R_20242182001_02H_10Z_MO) which converts all the satellite constellations tracked by the antenna (GPS, GLONASS, Bideau, and Galileo). An example of the RINEX 2.11 filename is TVEE219A.24O where the convention TVEE is the four-letter site name, 219 is the day of year, A is the session A-Z, 24 is the year, O represents the observation file, N is the navigation file, M is meteorological file, and G is the GLONASS navigation message file. An example of the RINEX 3.04 filename is TVEE00000_R_20242182001_02H_10Z_MO where the convention TVEE00000 is the nine-letter site name, R is the data source (R - receiver), 20242182001 is the year (2024), day of year (218), and UTC start time of the file in HHMM (2001), 02H is the file time (2 hours), and the 10Z is the recording rate (10 Hz), MO is the mixed observation file, MN is the mixed navigation file, and MM is meteorological file. Spectra Precision proprietary G-Files 2024 RINEX version 2.11 format files. RINEX version 3.04 format files. Nancy T. DeWitt U.S. Geological Survey Geologist mailing and physical address

600 4th Street South

St. Petersburg FL 33701-4846 USA 727-502-8000 ndewitt@usgs.gov Single-Beam Bathymetry Acquisition: A total of 583 line-km of SBES data were collected as part of FAN 2024-320-FA: the R/V G. Hill (TVEE - 24BIM07) collected 308.60 line-km, R/V Shark (WVR1- 24BIM08) collected 151.82 line-km, and R/V Chum (WVR2-24BIM09) collected 122.47 line-km of data. Boat motion (heave, roll, pitch) was recorded on each vessel at 50-millisecond (ms) intervals using an SBG Ellipse Series A motion sensors. HYPACK®, a marine surveying, positioning, and navigation software package, managed the planned-transect information and provided real-time navigation parameters, course corrections, data quality parameters, and instrumentation-status to the boat operator. Depth soundings were recorded at 50-ms intervals using a Teledyne Odom ECHOTRAC CV100 echosounder with a 4-degree, 200-kilohertz (kHz) transducer on the TVEE, WVR1, and WVR2. For each vessel, data from the GNSS receiver, motion sensor, and echosounder were recorded in real-time and merged into a single raw data file (.RAW) in HYPACK®, with each device string referenced by a device identification code and time stamped to Coordinated Universal Time (UTC). Sound velocity profile (SVP) measurements were collected using SonTek Castaway-CTD® (Conductivity, Temperature, and Depth) instruments. The CTD units were cast overboard to record changes in water column speed of sound (SOS) spatially and temporally. A total of 312 casts recorded sound velocities ranging from 1522.24 to 1545.26 meters per second (m/s) at water depths ranging from a minimum of -0.15 m to a maximum of -10.80 m. 2024 *.RAW, *.BIN, *.LOG,*.ctdx, *.ctd, *.csv, *.svp Nancy T. DeWitt U.S. Geological Survey Geologist mailing and physical address

600 4th Street South

St. Petersburg FL 33701-4846 USA 727-502-8000 ndewitt@usgs.gov Differentially Corrected Navigation Processing: All navigation data were acquired in WGS84 (G2296)/International Reference frame 2020 (ITRF2020) which was introduced on January 7, 2024. The survey acquisition dates occurred after this date. The latest processing software program versions were limited to WGS84 (G2139); therefore, it was the realization used for post-processing the navigation data. The base station data were post-processed through NOAA NGS OPUS, and the coordinate values were derived from the time-weighted average of values produced by OPUS. The 2024 GNSS base occupations were within +/- 3 standard deviations of the 2022-time weighted average coordinates, therefore the 2022 WGS84 (G2139) coordinates from Lyons and others (2024) were able to be used for post-processing the navigation data collected during this survey. The 2022 WGS84 (G2139) coordinates used were 29° 29' 38.33200" North, 89° 10' 29.28105" West, -25.253 m ellipsoid height, and epoch 2022.590 (BRET). To check the difference between realizations (G2139 and G2296), the BRET base station coordinates were sent through HTDP online and the resultant difference was 0.00006 latitude seconds, 0.00005 longitude seconds, and 0.00 meters ellipsoid height. The rover data, base data, and the base station coordinates were imported into GrafNav, NovAtel's Waypoint software (NovAtel, 2023). Each kinematic GNSS data session from the survey vessel was post-processed to the concurrent static base GNSS data session. GNSS data plots and data information generated by GrafNav including satellite health (satellite lock, satellite cycle slips), rover trajectory maps, and pre-processing logs were used to modify the processing parameters to attain trajectory solutions (between the base and the rover) that resulted in fixed positions. Primary examples include: 1) excluding satellites, flagged by GrafNav, with bad health or frequent cycle slips, 2) omitting satellite time segments that introduce positional errors which prevented a fixed solution, or 3) adjusting the satellite elevation mask angle to improve the position solutions (NovAtel, 2023). The final differentially corrected, precise DGPS positions were computed at 0.1s and exported as single data point epochs in ASCII text format in WGS84 (G2139) UTM 16N geodetic datum. RINEX version 3.04 format files. 2025 *.txt Nancy T. DeWitt U.S. Geological Survey Geologist mailing and physical address

600 4th Street South

St. Petersburg FL 33701-4846 USA 727-502-8000 ndewitt@usgs.gov Single-beam Bathymetry Processing: All data were processed using HYPACK® 2023 following steps outlined in the HYPACK® 2023 User Manual (Xylem, 2023). First, the HYPACK® project geodesy settings were verified, ensuring the correct UTM Zone and "K-N from User" settings with "height of ellipsoid above chart datum" value of '0.00' were selected. Next, the .RAW data files were imported into HYPACK® Single Beam Editor (64 bit). The following "Read Parameters" were selected within the Survey Tab 'Elevation Mode' and the project information was verified. Within the Corrections Tab: the sound velocity profiles (SVP) were added as .VEL format, and 'Time and Position' was selected for the SVP interpolation method. Within the Devices Tab: the vessel offsets were added and the RTK Tides box was selected. Within the Processing Tab: 'Apply Heave Correction', 'Correct Induced Heave', 'Remove Heave Drift', 'Avoid Double Heave', 'Merge Tide Data with Heave', 'Interpolate Draft', 'Apply Pitch and Roll Corrections', and 'Steer Sounding Beam' (4 degree for the TVEE, WVR1, and WVR2) were all selected. The data were then processed within HYPACK®'s Single Beam Editor (64 bit). Next, the GPS Adjustment tool was used to merge the post-processed navigation trajectory epoch solutions with their respective HYPACK® data files (.RAW). Using the Editor Profile window, these processed soundings were visually scanned for any resultant outliers which were manually removed using the editor tool. The data were then smoothed using the smoothing option with the 'number of samples for average" set to 60. Finally, the x,y,z data (easting, northing, ellipsoid height) and associated attributes (calendar date, UTC time, and line number) were exported as a single text file per line. The text files were then combined into one file per subFAN/vessel using the ArcGIS Pro 'Merge (Data Management)' geoprocessing tool, resulting in three main text files. *.RAW, *.BIN, *.LOG, *.VEL, *.INI 2024 24BIM07_TVEE_PP_Merg.txt 24BIM08_WVR1_PP_Merg.txt 24BIM09_WVR2_PP_Merg.txt Nancy T. DeWitt U.S. Geological Survey Geologist mailing and physical address

600 4th Street South

St. Petersburg FL 33701-4846 USA 727-502-8000 ndewitt@usgs.gov Quality Control, Quality Assurance (QA/QC) and Uncertainty Analysis: Using ArcGIS Pro, the processed single-beam datasets were then transformed into feature classes using the "Create Points From Table > XY Table to Point" geoprocessing tool and the spatial reference was set to WGS84 UTM 16N. Next, a polyline feature class (representing tracklines) was produced from the point data using XTools Pro "Make Polylines from Points" (the selection criteria being HYPACK® line name and then ordering by UTC time). Utilizing both the point and polyline feature classes, an ArcGIS Pro Python script was used to evaluate the elevation differences at the intersections of tracklines. The script does this by calculating the elevation difference between points at each intersection using an inverse distance weighting equation with a search radius of 1 m. The crossing analysis yielded a Root Mean Square Error (RMSE) of 5.44 cm for all crossings. When the TVEE crossed one of its own lines, the crossing analysis yielded an RMSE of 4.11 cm. When the WVR1 crossed one of its own lines, the crossing analysis yielded a RMSE of 4.20 cm. When the WVR2 crossed one of its own lines, the crossing analysis yielded a RMSE of 4.14 cm. When the TVEE crossed WVR1, the crossing analysis yielded and RMSE of 8.10 cm. When the TVEE crossed WVR2, the crossing analysis yielded and RMSE of 6.5 cm. When WVR1 crossed WVR2, the crossing analysis yielded an RMSE of 6.00 cm. The crossings in ArcGIS Pro were solely used as a QA/QC, not as a means of editing the data. 24BIM07_TVEE_PP_Merg.txt 24BIM08_WVR1_PP_Merg.txt 24BIM09_WVR2_PP_Merg.txt 2025 Breton_Island_SBES_2024_WGS84_G2139_xyz.txt Breton_Island_SBES_2024_WGS84_G2139_tracklines.shp Nancy T. DeWitt U.S. Geological Survey Geologist mailing and physical address

600 4th Street South

St. Petersburg FL 33701-4846 USA 727-502-8000 ndewitt@usgs.gov Datum Transformation: NOAA NGS's VDatum software was used to transform the single-beam data points' horizontal (x,y) and vertical (z) datums from WGS84 (G2139) UTM 16N (horizontal), WGS84 (G2139) ellipsoid height (vertical) using epoch year 2024.596 (start of the survey) to NAD83 UTM 16N (horizontal), NAVD88 orthometric height (vertical) using GEOID18 epoch year 2010.000 (the reference epoch for the NAD83[2011] realization). The VDatum-reported vertical uncertainty is 0.045 m. For more information about the positional accuracy for these datum transformations, visit the Estimation of Vertical Uncertainties VDatum webpage, https://vdatum.noaa.gov/docs/est_uncertainties.html. Breton_Island_SBES_2024_WGS84_G2139_xyz.txt 2025 Breton_Island_2024_SBES_NAD83_NAVD88_UTM16N_GEOID18_xyz.txt Nancy T. DeWitt U.S. Geological Survey Geologist mailing and physical address

600 4th Street South

St. Petersburg FL 33701-4846 USA 727-502-8000 ndewitt@usgs.gov Point Point 3,877,228 Universal Transverse Mercator 16N 0.999600 -87.000000 0.000000 500000.000000 0.000000 coordinate pair 0.6096 0.6096 meters World Geodetic System of 1984 WGS_1984 6378137.000000 298.257223563 World Geodetic System of 1984 0.01 meters Attribute values Breton_2024_SBES_WGS84_UTM16N_xyz.txt Comma-delimited ASCII text file (.txt) containing the processed single-beam bathymetry data points from USGS FAN 2024-320-FA (subFANs 24BIM07, 24BIM08, and 24BIM09). Data are in the processing datum WGS84 (G2139) UTM Zone 16N. U.S. Geological Survey X_EASTING_WGS84(G2139) x-axis coordinate, easting, WGS84 (G2139) UTM 16N. U.S. Geological Survey 283047.57 296933.17 meters Y_NORTHING_WGS84(G2139) y-axis coordinate, northing, WGS84 (G2139) UTM 16N. U.S. Geological Survey 3256790.92 3269200.21 meters ELLIPSOID_WGS84(G2139) z-value, ellipsoid height (elevation), WGS84 UTM16N. U.S. Geological Survey -37.25 -25.82 meters YEAR Year (YYYY) of data acquisition. U.S. Geological Survey 2024 2024 DOY Day of year of data acquisition. U.S. Geological Survey 219 223 UTC_TIME Universe Coordinate Time (UTC) of data acquisition. U.S. Geological Survey 13:42:29.620 23:01:02.081 HH:MM:SS.sss HYPACK_LINE Identifier assigned to each HYPACK® line during acquisition. HYPACK®/U.S. Geological Survey Line name example 24BIM08_WVR1_0034_2002, where the first 7 characters are the subFAN followed by underscore (24BIM08_), the next 4 characters are the platform/vessel followed by an underscore (WVR1_), and the last 9 characters are the HYPACK® line number and start time (HHMM) in UTC separated by and underscore (0034_2002). If the same line name had multiple segments a 4-digit number was appended after the line number (for example, _0001). Breton_Island_2024_SBES_NAD83_NAVD88_UTM16N_GEOID18_xyz.txt Comma-delimited ASCII text file (.txt) containing the processed single-beam bathymetry data points from USGS FAN 2024-320-FA (subFANs 24BIM07, 24BIM08, and 24BIM09). Data were transformed from its native datum to NAD83 NAVD88 UTM Zone 16 North coordinate system with respect to the GEOID 18 datum. VDatum X_EASTING_NAD83(2011) x-axis coordinate, easting, NAD83 (2011) UTM 16N. VDatum 283048.452 296934.049 meters Y_NORTHING_NAD83(2011) y-axis coordinate, northing, NAD83 (2011) UTM 16N. VDatum 3256790.354 3269199.64 meters ORTHOMETRIC_NAVD88_GEOID18 z-value, orthometric height adjusted (elevation) in NAVD88 GEOID 18. VDatum -11.457 -0.085 meters YEAR Year (YYYY) of data acquisition. U.S. Geological Survey 2024 2024 DOY Day of year of data acquisition. U.S. Geological Survey 219 223 UTC_TIME Universe Coordinate Time (UTC) of data acquisition. U.S. Geological Survey 13:42:29.620 23:01:02.081 HH:MM:SS.s HYPACK_LINE Identifier assigned to each HYPACK® line during acquisition. HYPACK®/U.S. Geological Survey Line name example 24BIM08_WVR1_0034_2002, where the first 7 characters are the subFAN followed by underscore (24BIM08_), the next 4 characters are the platform/vessel followed by an underscore (WVR1_), and the last 9 characters are the HYPACK® line number and start time (HHMM) in UTC separated by and underscore (0034_2002). If the same line name had multiple segments a 4-digit number was appended after the line number (for example, _0001). Breton_Island_SBES_2024_WGS84_Tracklines.shp Polyline shapefile of the single-beam bathymetry tracklines (222 lines in total). U.S. Geological Survey FID Automatically generated feature attribute by Esri. Esri 1 222 Shape Automatically generated feature attribute by Esri. Esri Polyline ZM Shape_Leng Length of the trackline polyline, in meters. Esri 6.69 8264.36 meters HYPACK_line Identifier assigned to each HYPACK® line during acquisition. HYPACK®/U.S. Geological Survey Line name example 24BIM08_WVR1_0034_2002, where the first 7 characters are the subFAN followed by underscore (24BIM08_), the next 4 characters are the platform/vessel followed by an underscore (WVR1_), and the last 9 characters are the HYPACK® line number and start time (HHMM) in UTC (0034_2002). If the same line name had multiple segments a 4-digit number was appended after the line number (for example, _0001). U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center USGS SPCMSC Data Management mailing and physical

600 4th Street South

Saint Petersburg FL 33701-4846 United States 727-502-8000 gs-g-spcmsc_data_inquiries@usgs.gov Breton_Island_2024_SBES_WGS84_UTM16N_xyz.txt, Breton_Island_2024_SBES_NAD83_NAVD88_UTM16N_GEOID18_xyz.txt, Breton_Island_SBES_2024_WGS84_UTM16N_Tracklines.shp 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. comma-delimited text, shapefile ZIP https://coastal.er.usgs.gov/data-release/doi-P14M8EZU/data/Breton_Island_2024_SBES_WGS84_UTM16N_xyz.zip https://coastal.er.usgs.gov/data-release/doi-P14M8EZU/data/Breton_Island_2024_SBES_NAD83_NAVD88_UTM16N_GEOID18_xyz.zip https://coastal.er.usgs.gov/data-release/doi-P14M8EZU/data/Breton_Island_SBES_2024_WGS84_UTM16N_tracklines.zip None 20260423 U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center USGS SPCMSC Data Management mailing and physical

600 4th Street South

Saint Petersburg FL 33701-4846 United States 727-502-8000 gs-g-spcmsc_data_inquiries@usgs.gov Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998