Erin O. Lyons Julie C. Bernier Sydney K. Nick Daniel J. Ciarletta Jennifer L. Miselis 20250513 tabular and vector digital data Erin O. Lyons Julie C. Bernier Sydney K. Nick Daniel J. Ciarletta Jennifer L. Miselis 20250513 U.S. Geological Survey data release doi:10.5066/P1HFYGE6 St. Petersburg, Florida U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center https://doi.org/10.5066/P1HFYGE6 The U.S. Geological Survey St. Petersburg Coastal and Marine Science Center (USGS SPCMSC) collected single beam echosounder (SBES) and differential global positioning system (DGPS) elevation data in the nearshore and beach environments of Wallops and Assawoman Islands, Virginia, in June 2024. This USGS data release includes the processed SBES and DGPS elevation point data (xyz) for Field Activity Number (FAN) 2024-310-FA. The SBES data were acquired using survey equipment mounted on personal watercrafts (PWCs) R/V Chum and R/V Shark, and the DGPS data were acquired using GPS antennas mounted on a utility terrain vehicle (UTV) or GPS backpack. Multibeam echosounder (MBES) and chirp seismic data were collected concurrently as part of FAN 2024-310-FA; those data are available as separate data releases (Forde and others, 2025; Bemelmans and others, 2025). To map the shoreface morphology of Wallops and Assawoman Islands. These data may be used for assessment of coastal resiliency, erosion hazards, and (or) long-term landscape change. Data were collected during USGS Field Activity Number 2024-310-FA; vessel- specific SBES data were collected under subFANs 24BIM01 (R/V Shark - WVR1) and 24BIM02 (R/V Chum - WVR2). Additional survey and data details are available on the Coastal and Marine Geoscience Data System (CMGDS) at, https://cmgds.marine.usgs.gov/services/activity.php?fan=2024-310-FA. The xyz data are provided in: (1) Universal Transverse Mercator World Geodetic System 1984 (UTM-WGS84) in meters for the horizontal and WGS84 ellipsoidal height in meters for the vertical; and (2) Virginia State Plane Coordinate System 1983 (SPCS83) Federal Information Processing Standard (FIPS) 4502 in feet for the horizontal and North American Vertical Datum 1988 (NAVD88) in feet with respect to GEOID18 for the vertical. 20240601 20240613 ground condition Complete None planned -75.549313 -75.407008 37.895385 37.764644 USGS Metadata Identifier USGS:87975a34-89c2-42b2-ae5b-4069e0b06bd0 Global Change Master Directory EARTH SCIENCE > OCEANS > BATHYMETRY/SEAFLOOR TOPOGRAPHY > BATHYMETRY > COASTAL BATHYMETRY PROVIDERS > 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 ISO 19115 Topic Category geoscientificInformation elevation oceans location imageryBaseMapsEarthCover Common Geographic Areas Virginia United States None Wallops Island, Virginia Mid-Atlantic Coast None 2024 No access constraints. Please see 'Distribution Information' for details. 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. These data should not be used for navigational purposes. Julie C. Bernier 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 jbernier@usgs.gov Efforts were supported by the National Aeronautics and Space Administration (NASA) Wallops Island Shoreline Resiliency Study and the USGS Interconnected Coastal Environments at Decadal Timescales (ICED-T) and Coastal Sediment Availability and Flux (CSAF) projects. Funding and (or) support for this study were provided by the National Aeronautics and Space Administration through authorization under the Economy Act (31 U.S.C. § 1535). Environment as of Metadata Creation: Microsoft Windows 11 Enterprise Version 23H2 (Build 22631.4317); Environmental Systems Research Institute (Esri) ArcGIS Pro version 3.3.2; National Oceanic and Atmospheric Administration (NOAA) National Geodetic Survey (NGS) VDatum software version 4.7.0 (https://vdatum.noaa.gov/); NGS Online Positioning User Service (OPUS, https://geodesy.noaa.gov/OPUS/); NovAtel’s GrafNav, version 9.00.0731; Horizontal Time-Dependent Positioning (HTDP) online transformation utility version 3.5.0; HYPACK® A Xylem Brand version 22.3.4.0; R-Studio (2024.04.02 Build 764). Erin O. Lyons Chelsea A. Stalk Jennifer L. Miselis Noreen A. Buster Julie C. Bernier Nancy T. DeWitt 20250325 U.S. Geological Survey data release doi:10.5066/P1HJAVAR St. Petersburg, Florida U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center https://doi.org/10.5066/P1HJAVAR Arnell D. Forde Chelsea A. Stalk Daniel J. Ciarletta Jennifer L. Miselis 20250318 U.S. Geological Survey data release doi:10.5066/P1NZ6CC2 St. Petersburg, Florida U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center https://doi.org/10.5066/P1NZ6CC2 Christopher C. Bemelmans Chelsea A. Stalk Daniel J. Ciarletta Jennifer L. Miselis 20250513 U.S. Geological Survey data release doi:10.5066/P14SGUMT St. Petersburg, Florida U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center https://doi.org/10.5066/P14SGUMT NovAtel 2020 Alberta, Canada Novatel Inc. https://hexagondownloads.blob.core.windows.net/public/Novatel/assets/Documents/Manuals/Waypoint-Software-User-Manual-OM-20000166/Waypoint_8.90_Software_User_Manual.pdf Xylem 2021 Middletown, CT a Xylem brand https://www.xylem.com/siteassets/brand/hypack/resources/manual/hypack-2021-user-manual.pdf This SBES dataset is derived from one field activity using similar or identical equipment set-ups and acquisition settings between survey platforms; therefore, the dataset is internally consistent. During mobilization, internal- and external-offsets were measured for each piece of equipment relative to the appropriate survey vessel. All measurements were recorded manually, and then digitally entered into the acquisition and processing software. Offsets between the SBES transducers, motion reference units, and antenna reference points (ARPs) were measured using a geodimeter and accounted for during acquisition and (or) in post-processing. DGPS coordinates were obtained by post-processing through NGS OPUS and NovAtel’s Waypoint Product Group GrafNav software. The beach elevation dataset is derived from one field activity using similar or identical equipment set-ups and acquisition settings between surveyors; therefore, the dataset is internally consistent. During mobilization, antenna heights were measured prior to survey initiation. For backpack surveys, the distance between the ground and the antenna was measured for each surveyor both standing upright and mid-stride. For vehicle surveys, the distance between the ground and the antenna was measured pre- and post-survey. All measurements were recorded manually, and then digitally entered into the acquisition and processing software. DGPS coordinates were obtained by post-processing through NGS OPUS and NovAtel’s Waypoint Product Group GrafNav software. These data were collected during a single survey using two PWCs with consistent instrument calibrations. This data release contains SBES bathymetry and beach elevation data points in horizontal position and vertical elevation (xyz) from June 2024 collected at Wallops Island, Virginia. Users are advised to read the complete metadata record carefully for additional details. Base stations were established on two local control points located on the NASA Wallops Island Flight Facility stamped G 421 1963 (NGS Permanent Identifier [PID] FW0494; designated G421 for USGS data acquisition and processing) and WFF06. The coordinate values of both GPS base stations are the time-weighted average of values obtained from NGS OPUS. The estimated horizontal accuracy (2-sigma) of the post-processed base coordinates is +/- 0.00020 seconds latitude and +/- 0.00027 seconds longitude for G421 and +/- 0.00020 seconds latitude and +/- 0.00031 seconds longitude for WFF06. Positional accuracy was determined by post-processed differential correction using a base/rover setup using NovAtel’s Waypoint GrafNav software. 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 single beam kinematic (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). For the single beam data, the estimated post-processed horizontal accuracy (2-sigma) for all kinematic rover data to the WFF06 benchmark was 0.011 +/- 0.0039 meters (m). The estimated post-processed horizontal accuracy (2-sigma) for all kinematic rover data to the G421 benchmark was 0.012 +/- 0.0030 m. For the beach elevation data, the estimated post-processed horizontal accuracy (2-sigma) for all kinematic rover data to the WFF06 benchmark was 0.012 +/- 0.024 m. The estimated post-processed horizontal accuracy (2-sigma) for all kinematic rover data to the G421 benchmark was 0.011 +/- 0.055 m. As described above, coordinate values for the base stations were the time-weighted average of values from the NGS OPUS and location information associated with each SBES survey line was determined by post-processed differential correction using a base/rover setup using NovAtel’s Waypoint GrafNav software. The estimated vertical accuracy (2-sigma) of the post-processed base coordinates for both base stations (G214 and WFF06) are +/- 0.018 m. For the SBES data, the estimated post-processed vertical accuracy (2-sigma) for all kinematic rover data to the WFF06 benchmark was 0.017 +/- 0.006 m. The estimated post-processed vertical accuracy (2-sigma) for all kinematic rover data to the G421 benchmark was 0.019 +/- 0.005 m. For the beach elevation data, the estimated post-processed vertical accuracy (2-sigma) for all kinematic rover data to the WFF06 benchmark was 0.018 +/- 0.044 m. The estimated post-processed vertical accuracy (2-sigma) for all kinematic rover data to the G421 benchmark was 0.017 +/- 0.059 m. The combined estimated post-processed local level position error (2-sigma) (east, north, and up axes) for all SBES kinematic rover data to the WFF06 benchmark was 0.020 +/- 0.0069 m. The combined estimated post-processed local level position error (2-sigma) (east, north, and up axes) for all SBES kinematic rover data to the G421 benchmark was 0.023 +/- 0.0057 m. The combined estimated post-processed local level position error (2-sigma) (east, north, and up axes) for all beach elevation kinematic rover data to the WFF06 benchmark was 0.022 +/- 0.051 m. The combined estimated post-processed local level position error (2-sigma) (east, north and up axes) for all beach kinematic rover data to the G421 benchmark was 0.021 +/- 0.082 m. GNSS Acquisition: Two Global Navigational Satellite Systems (GNSS) base stations were established on WFF06 and G421 benchmarks; each base station was continually occupied and equipped with a Spectra Precision SP90M GNSS receiver recording full-carrier-phase positioning signals from satellites at a rate of 0.1 second (s) via a Trimble Zephyr 3 Base GNSS antenna. A similar set-up was used on each of the rover vessels except that the GNSS antennas varied by platform (PWCs – SP90M GNSS receiver Spectra Precision SPGA Rover antenna; beach elevation surveys – Spectra Precision SP-80 or SP-85 integrated GNSS receiver and antenna mounted on a UTV or GPS backpack). The maximum SBES processing baseline between the WFF06 benchmark and rover vessels was 10.23 kilometers (km). The maximum SBES processing baseline between the G421 benchmark and rover vessels was 13.90 km. The maximum beach processing baseline between the WFF06 benchmark and rover vessels was 7.33 km. The maximum beach processing baseline between the G421 benchmark and rover vessels was 11.11 km. 2024 Julie C. Bernier 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 jbernier@usgs.gov Single-Beam Bathymetry Acquisition: A total of 544.60 line-km of SBES data were collected as part of FAN 2024-310-FA: the R/V Shark collected 275.59 line-km and the R/V Chum collected 269.01 line-km. Boat motion was recorded on each vessel at 50-millisecond (ms) intervals using a SBG Ellipse A motion sensor. HYPACK® A Xylem Brand, a marine surveying, positioning, and navigation software package, managed the planned-transect information and provided real-time navigation, steering, correction, data quality, and instrumentation status to the boat operator. Depth soundings were recorded at 50-ms intervals using an Odom echotrac CV100 echosounder with a 4-degree, 200-kilohertz (kHz) transducer on the R/V Shark and the R/V Chum. 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 Conductivity, Temperature, and Depth (CTD) instruments. The instruments were periodically cast overboard to record changes in water column speed of sound (SOS). A total of 43 successful sound velocity casts were collected and ranged in depth from 0.14 to 9.63 m, and in sound velocity from 1498.47 to 1522.07 meters per second (m/s). 2024 Julie C. Bernier 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 jbernier@usgs.gov Differentially Corrected Navigation Processing: All navigation data were acquired in the World Geodetic System 1984 (WGS84). The latest realization of WGS84 (G2139) was introduced on 01/03/21. The survey acquisition dates followed this date; therefore, it was the realization used for post-processing the navigation data. Base station data were post-processed through NGS OPUS, and the coordinate values of each base station was derived from the time-weighted average of values obtained from NGS OPUS. The NGS published elevation for base station G421, which was last determined by differential leveling in 1991, was more than 3 standard deviations outside of the OPUS-derived time-weighted average elevation; therefore, the coordinate values derived from this survey were used for post-processing. Similarly, because there are no published coordinates for base station WFF06, the time-weighted average coordinate values derived from this survey were used for post-processing. The WGS84 (G2139) coordinates used for post-processing the navigation collected during this survey were 37° 51' 51.95987" North, 75° 30' 26.38946" West, -32.969 m ellipsoid height (G421) and 37° 51' 45.73588" North, 75° 30' 33.10669" West, -32.545 m ellipsoid height (WFF06). The kinematic trajectories (rover to base) and base station coordinates were imported to NovAtel’s Waypoint GrafNav software. Each kinematic GNSS data session from the survey vessel was post-processed to the concurrent base GNSS data session. Satellite and data plots, trajectory maps, and processing logs that GrafNav produces provide information that can be used to modify processing parameters to attain trajectory solutions (between the base and the rover) free of erroneous data that result in fixed positions. Some examples include 1) excluding satellites flagged by the program as having poor health or cycle slips, 2) excluding satellite time segments that introduce positional errors that prevent a fixed solution, or 3) adjusting the satellite elevation mask angle to improve the position solutions (NovAtel, 2020). The final differentially corrected, precise DGPS positions were computed at 0.1s and 0.5s for SBES and beach surveys, respectively, and exported in American Standard Code for Information Interchange (ASCII) text format in WGS84 (G2139) UTM Zone 18 North (18N) geodetic datum. These processing steps were repeated for all navigation data for both the single beam and the beach elevation datasets. 2024 Julie C. Bernier 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 jbernier@usgs.gov Bathymetry Processing: All data were processed in HYPACK using the following steps outlined in the HYPACK 2021 User Manual (Xylem, 2021). First, Geodesy settings were confirmed, ensuring the correct UTM Zone and K-N from User Settings with a user value of 0.00 for Real-Time Kinematic (RTK) Tide were used. Next, data were processed in the Single Beam Editor (64 bit). The following settings were used within the Read Parameters window: the survey tab highlighted ‘Elevation Mode’ and was filled with project information. Under the Corrections Tab, the sound velocity profiles (SVP) were added as a VEL file and ‘Time and Position’ was utilized as the SVP interpolation method. Under the Devices Tab, the vessel offsets were added and saved to a vessel-specific .INI file, ensuring RTK Tides was selected. Under 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’ were all selected and applied to each sounding. Next, the GPS Adjustment tool was used to incorporate the post-processed navigation files. Outlier soundings, identified as distant from otherwise coherent and consistent soundings, were manually removed, and the data were smoothed using the smoothing tool with the default settings. The xyz (easting, northing, and ellipsoid height, in meters) data were exported as a text file referenced to WGS84 (G2139) UTM zone 18N. Each line was exported as a single text file and then merged in R-Studio (2024.04.02 Build 764), a computing software, by vessel identifier (24BIM01, etc.) to create one individual text file for each survey vessel. 2024 Daniel J. Ciarletta 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 dciarletta@usgs.gov Offset Analysis and Correction: Internal quality assurance and quality control (QA/QC) of the SBES xyz data identified a vertical offset between the two SBES datasets and concurrently collected multibeam data (Bemelmans and others, 2025) of 27 centimeters (cm), with the MBES data sitting shallower. The vertical offset between the SBES and MBES surveys is consistent with offset findings from Lyons and others (2025) for the same vessels, confirming the need to adjust this dataset. To accurately identify true changes in the seafloor and not changes associated with hardware differences, vertical offsets were quantified between the transducers for each vessel. First, data for each vessel were imported into ArcGIS Pro and the ‘XY Table to Point’ geoprocessing tool was used to create the point file. Next, the ‘Spatial Join’ tool was used three individual times to join points from a set of two vessels (WVR1-WVR2, WVR1-MBES, and WVR2-MBES) using the tool inputs of closest geodesic point within a 0.5 m (MBES-WVR1/WVR2) or 1 m (WVR1-WVR2) search radius. All 3 joins were exported to Excel using the ‘Table to Excel’ tool. The offset between each vessel set (A and B) was calculated in Excel by averaging the absolute difference in elevation at each joined point. The offsets of the post-processed HYPACK data, prior to adjustment, were as follows: the MBES and WVR1 SBES had an average offset of 27.25 cm and a root mean squared error (RMSE) of 27.73 cm. The MBES and WVR2 SBES had an average offset of 27.18 cm and an RMSE of 27.52 cm. The WVR1 and WVR2 SBES had an average offset of 5.35 cm and an RMSE of 9.32 cm. Due to offsets between SBES and MBES sensors that exceeded system errors, linear regression was used to compare SBES and MBES soundings. SBES data were adjusted using y = 0.9848x - 0.942 for WVR1 and y = 0.9967x - 0.4175 for WVR2. For each equation, x represents MBES elevations and y represents SBES elevations. The adjustments were calculated in R-Studio, a computing software, and all adjusted data were appended to the files in this data release as a new attribute (_adjusted), retaining the original elevation data column. 2023 Daniel J. Ciarletta 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 dciarletta@usgs.gov Uncertainty Analysis: The SBES data was exported from HYPACK (xyz ASCII text file) and merged into one file for each vessel using a script in R-Studio, a computing software. Each vessel .txt file was imported into Esri ArcGIS Pro as a point shapefile (.shp) using the "XY Table to Point" geoprocessing tool. The horizontal datum projection was set to WGS84 UTM 18N. The shapefiles were visually reviewed for any obvious outliers or problems. Next, polyline shapefiles (representing tracklines) were produced from the point shapefiles using the "Points to Line" geoprocessing tool for each survey platform (subFANs 24BIM01 and 24BIM02). Utilizing both the xyz (point) and trackline (polyline) shapefiles, a Python script in ArcGIS Pro was used to evaluate elevation differences at the intersection of crossing tracklines by calculating the elevation difference between points at each intersection using an inverse distance weighting equation with a search radius of 3 m. The crossing analysis yielded a 7.99 cm RMSE for all crossings. When the R/V Chum crossed one of its own lines, the crossing analysis yielded a 4.28 cm RMSE. When the R/V Shark crossed one of its own lines, the crossing analysis yielded a 6.53 cm RMSE. The crossings analyses in ArcGIS Pro were solely used as a QA/QC. The data were further cleaned in ArcGIS Pro to remove any loops, tight turns, or data that were off the planned lines, and point datasets was exported as the final data product (xyz text file). The beach xyz DGPS data were similarly merged into a single file, imported into ArcGIS Pro, and analyzed using the crossing program with a search radius of 3 m. For the beach data, any time survey tracks crossed, the crossing analysis yielded a 19.04 cm RMSE. 2024 Wallops_Island_2024_SBES_WGS84_UTM18N_xyz.txt Wallops_Island_2024_Beach_WGS84_UTM18N_xyz.txt Wallops_Island_2024_SBES_WGS84_UTM18N_Tracklines.shp Wallops_Island_2024_Beach_WGS84_UTM18N_Tracklines.shp Daniel J. Ciarletta 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 dciarletta@usgs.gov Datum Transformation: NOAA NGS's VDatum was used to transform the SBES and beach DGPS data points' horizontal and vertical datums (xyz). The data were transformed from WGS84 (G2139) UTM 18N to NAD83 (horizontal) State Plane Virginia (FIPS 4502) and NAVD88 (vertical) using GEOID18 with a reported vertical uncertainty of 0.119 feet (SBES) and 0.122 feet (DGPS). 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. Wallops_Island_2024_SBES_WGS84_UTM18N_xyz.txt Wallops_Island_2024_Beach_WGS84_UTM18N_xyz.txt 2024 Wallops_Island_2024_Beach_NAD83_FIPS4502_NAVD88_G18_xyz.txt Julie C. Bernier 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 jbernier@usgs.gov Point Point 3782867 Universal Transverse Mercator 18N 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 Wallops_Island_2024_SBES_WGS84_UTM18N_xyz.txt Comma-delimited ASCII text file (.txt) containing the processed SBES bathymetry data points from USGS FAN 2024-310-FA (subFANs 24BIM01 and 24BIM02) for all track lines. Data are in the native acquisition and processing datum WGS84 (G2139) UTM Zone 18N. U.S. Geological Survey WGS84_UTM18N_X x-axis coordinate, easting, WGS84 UTM 18N. U.S. Geological Survey 451630.68 464206.24 meters WGS84_UTM18N_Y y-axis coordinate, northing, WGS84 UTM 18N. U.S. Geological Survey 4179833.89 4194289.52 meters WGS84_ELLIPSOID z-value, ellipsoid height (elevation), WGS84 U.S. Geological Survey -48.20 -38.00 meters UTC_DATE Date in m/dd/yyyy. U.S. Geological Survey 6/1/2024 6/12/2024 UTC_TIME UTC time of data acquisition. U.S. Geological Survey 00:00:00.000 22:08:05.975 HH:MM:SS.sss HYPACK_LINE Identifier assigned to each HYPACK® line during acquisition. HYPACK®, U.S. Geological Survey For most lines, the naming convention uses the format 24BIM##_WVR#_LINE_TIME, where 24BIM## is the subFAN, LINE is the 4 digit HYPACK line number, TIME is the 4 digit start time in UTC, and WVR# is the vessel (WVR1 or WVR2). If the line was acquired in multiple segments a 4 digit segment number is appended after the time stamp (for example, _0001). WGS84_ELLIPSOID_ADJUSTED z-value, ellipsoid height (elevation) in WGS84, adjusted after offset analysis. VDatum -47.987 -37.707 meters Wallops_Island_2024_Beach_WGS84_UTM18N_xyz.txt Comma-delimited ASCII text file (.txt) containing the processed beach DGPS elevation data points from USGS FAN 2024-310-FA. Data are in the native acquisition and processing datum WGS84 (G2139) UTM Zone 18N. U.S. Geological Survey ANT_HEIGHT Height of pole or tripod above the station marker. U.S Geological Survey 1.411 2.182 meters UTC_DATE Calendar date in mm/dd/yyyy. U.S. Geological Survey 06/01/2024 06/13/2024 mm/dd/yyyy UTC_TIME UTC time of data acquisition. U.S. Geological Survey 11:15:48.0 22:44:34.0 HH:MM:SS.s LOCAL_TIME Local time of data acquisition. U.S. Geological Survey 06:15:48.0 17:44:34.0 HH:MM:SS.s WGS84_UTM18N_X x-axis coordinate, easting, WGS84 UTM18N. U.S. Geological Survey 452356.218 463047.284 meters WGS84_UTM18N_Y y-axis coordinate, northing, WGS84 UTM18N. U.S. Geological Survey 4180202.964 4194234.126 meters SD_HORIZ Estimated local level position error (east and north axes). GrafNAV 0.005 1.990 meters WGS84_ELLIPSOID z-value, ellipsoid height (elevation), WGS84. U.S. Geological Survey -39.123 -34.436 meters SD_HEIGHT Estimated local level position error (vertical axis). GrafNAV 0.008 0.839 meters STD_DEV Estimated combined local level position error (east, north and up axes). GrafNAV 0.011 2.160 meters SURF_DIST Horizontal distance for vectors on the surface (corrected geodesic). GrafNAV 3158.352 11113.729 meters DOY Day of Year of data acquisition. U.S. Geological Survey 153 165 SESSION Identifier assigned to each DGPS session during acquisition and processing. U.S. Geological Survey Session names use the format 2024_DOY_ROVR_BASE_WGS84_S, where DOY is the day of year, as represented on the Julian calendar, the data were collected, ROVR identifies the rover GPS receiver used (A2AS or A2WA), BASE identifies the base station used for processing (G421 or WFF6), WGS84 is the processing datum, and S is the GPS session number, which counts up alphabetically from A each day for each rover GPS. TYPE Identifier assigned to the type of survey used in acquisition. U.S. Geological Survey Example: Pedestrian or UTV. Wallops_Island_2024_SBES_NAD83_FIPS4502_NAVD88_G18_xyz.txt Comma-delimited ASCII text file (.txt) containing the processed SBES bathymetry data points from USGS FAN 2024-310-FA (subFANs 24BIM01 and 24BIM02) for all track lines. Data were re-projected from the processing datum to NAD83 State Plane Virginia (FIPS 4502) in feet for the horizontal and NAVD88 in feet for the vertical coordinate system with respect to the GEOID 18 datum. U.S. Geological Survey FIPS4502_X x-axis coordinate, easting, NAD83 State Plane Virginia (FIPS 4502). VDatum 12335520.975 12375516.364 feet FIPS4502_Y y-axis coordinate, northing, NAD83 State Plane Virginia (FIPS 4502). VDatum 3815481.254 3864108.354 feet UTC_DATE Date of data acquisition in m/dd/yyyy. U.S. Geological Survey 6/1/2024 6/12/2024 UTC_TIME UTC time of data acquisition. U.S. Geological Survey 00:00:00.000 22:08:05.975 HH:MM:SS.sss HYPACK_LINE Identifier assigned to each HYPACK line during acquisition. HYPACK®, U.S. Geological Survey For most lines, the naming convention uses the format 24BIM##_WVR#_LINE_TIME, where 24BIM## is the subFAN, LINE is the 4 digit HYPACK line number, TIME is the 4 digit start time in UTC, and WVR# is the vessel (WVR1 or WVR2). If the line was acquired in multiple segments a 4 digit segment number is appended after the time stamp (for example, _0001). NAVD88_G18_ADJUSTED z-value, orthometric height (elevation) in NAVD88 GEOID 18, adjusted after offset analysis, in feet. VDatum -32.979 0.791 feet Wallops_Island_2024_Beach_NAD83_FIPS4502_NAVD88_G18_xyz.txt Comma-delimited ASCII text file (.txt) containing the processed beach DGPS elevation data points from USGS FAN 2024-310-FA. Data were re-projected from the processing datum to NAD83 State Plane Virginia (FIPS 4502) in feet for the horizontal and NAVD88 in feet for the vertical coordinate system with respect to the GEOID 18 datum. VDatum ANT_HEIGHT Height of pole or tripod above the station marker. U.S. Geological Survey 1.411 2.182 meters UTC_DATE Calendar date in mm/dd/yyyy. U.S. Geological Survey 06/01/2024 06/13/2024 mm/dd/yyyy UTC_TIME UTC time of data acquisition. U.S. Geological Survey 11:15:48.0 22:44:34.0 HH:MM:SS.s LOCAL_TIME Local time of data acquisition. U.S. Geological Survey 06:15:48.0 17:44:34.0 HH:MM:SS.s NAD83_FIPS4502_X x-axis coordinate, easting, NAD83 FIPS4502. VDatum 12338122.489 12371582.189 feet NAD83_FIPS4502_Y y-axis coordinate, northing, NAD83 FIPS4502. VDatum 3816562.078 3863844.762 feet SD_HORIZ Estimated local level position error (east and north axes). GrafNAV 0.005 1.990 meters NAVD88_G18 z-value, orthometric height (elevation) in NAVD88 GEOID 18. VDatum -3.868 11.542 feet SD_HEIGHT Estimated local level position error (vertical axis). GrafNAV 0.008 0.839 meters STD_DEV Estimated local level position error (east, north and up axes). GrafNAV 0.011 2.160 meters SURF_DIST Horizontal distance for vectors on the surface (corrected geodesic). GrafNAV 3158.352 11113.729 meters DOY Day of Year of data acquisition. U.S. Geological Survey 153 165 SESSION Identifier assigned to each DGPS session during acquisition. U.S. Geological Survey Session names use the format 2024_DOY_ROVR_BASE_WGS84_S, where DOY is the day of year, as represented on the Julian calendar, the data were collected, ROVR identifies the rover GPS receiver used (A2AS or A2WA), BASE identifies the base station used for processing (G421 or WFF6), WGS84 is the processing datum, and S is the GPS session number, which counts up alphabetically from A each day for each rover GPS. TYPE Identifier assigned to the type of survey used in acquisition. U.S. Geological Survey Example: Pedestrian or UTV. Wallops_Island_2024_SBES_WGS84_UTM18N_Tracklines.shp Polyline shapefile of all single beam bathymetry lines (446 lines) Esri, HYPACK®, U.S. Geological Survey FID Automatically generated feature attribute by Esri. Esri Sequential unique whole numbers that are automatically generated. Shape* Automatically generated feature attribute by Esri. Esri PolylineZM Shape_Leng Length of the trackline polyline, in meters. Esri 21.068461 6588.400904 meters line_name Identifier assigned to each HYPACK line during acquisition. HYPACK®, U.S. Geological Survey For most lines, the naming convention uses the format 24BIM##_WVR#_LINE_TIME, where 24BIM## is the subFAN, LINE is the 4 digit HYPACK line number, TIME is the 4 digit start time in UTC, and WVR# is the vessel (WVR1 or WVR2). If the line was acquired in multiple segments a 4 digit segment number is appended after the time stamp (for example, _0001). Wallops_Island_2024_Beach_WGS84_UTM18N_Tracklines.shp Polyline shapefile of all beach DGPS sessions (19 sessions) containing OBJECTID*, Shape*, Shape_Leng, and line_name. Esri, HYPACK®, U.S. Geological Survey FID Automatically generated feature attribute by Esri. Esri Sequential unique whole numbers that are automatically generated. Shape* Automatically generated feature attribute by Esri. Esri PolylineZM Shape_Leng Length of the trackline polyline, in meters. Esri 325.389 12034.170 meters Session Identifier assigned to each DGPS session during acquisition and processing. U.S. Geological Survey Session names use the format 2024_DOY_ROVR_BASE_WGS84_S, where DOY is the day of year, as represented on the Julian calendar, the data were collected, ROVR identifies the rover GPS receiver used (A2AS or A2WA), BASE identifies the base station used for processing (G421 or WFF6), WGS84 is the processing datum, and S is the GPS session number, which counts up alphabetically from A each day for each rover GPS. U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center USGS SPCMSC Data Management mailing and physical

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Saint Petersburg FL 33701 United States 727-502-8000 gs-g-spcmsc_data_inquiries@usgs.gov Wallops_Island_2024_SBES_NAD83_NAVD88_UTM18N_GEOID18_xyz.txt, Wallops_Island_2024_NAD83_NAVD88_UTM18N_GEOID18_Beach_xyz.txt, Wallops_Island_2024_SBES_WGS84_UTM18N_Tracklines.shp, Wallops_Island_2024_Beach_WGS84_UTM18N_Tracklines.shp, Wallops_Island_2024_SBES_WGS84_UTM18N_xyz.txt, Wallops_Island_2024_WGS84_UTM18N_Beach_xyz.txt 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-P1HFYGE6/data/Wallops_Island_2024_SBES_WGS84_UTM18N_xyz.zip https://coastal.er.usgs.gov/data-release/doi-P1HFYGE6/data/Wallops_Island_2024_SBES_NAD83_FIPS4502_NAVD88_G18_xyz.zip https://coastal.er.usgs.gov/data-release/doi-P1HFYGE6/data/Wallops_Island_2024_Beach_WGS84_UTM18N_xyz.zip https://coastal.er.usgs.gov/data-release/doi-P1HFYGE6/data/Wallops_Island_2024_Beach_NAD83_FIPS4502_NAVD88_G18_xyz.zip https://coastal.er.usgs.gov/data-release/doi-P1HFYGE6/data/Wallops_Island_2024_WGS84_UTM18N_Tracklines.zip None 20250513 U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center USGS SPCMSC Data Management mailing and physical

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