Chelsea A. Stalk
Andrew S. Farmer
Jennifer L. Miselis
20201005
Coastal Single-beam Bathymetry Data Collected in August 2019 from Cedar Island, Virginia
U.S. Geological Survey Data Release
doi:10.5066/P927Q8M1
St. Petersburg, FL
St. Petersburg Coastal and Marine Science Center
https://doi.org/10.5066/P927Q8M1
Scientists from the U.S. Geological Survey St. Petersburg Coastal and Marine Science Center (USGS - SPCMSC) in St. Petersburg, Florida, conducted a single-beam bathymetric survey of Cedar Island, Virginia, August 9-15, 2019. During this study, bathymetry data were collected aboard a towed seismic sled outfitted with a single-beam echosounder.
To evaluate shoreface morphology and geology along Cedar Island, Virginia, scientists from the USGS - SPCMSC conducted a bathymetric survey of Cedar Island, VA during Field Activity Number (FAN) 2019-332-FA. The objectives of the data collection were to map shoreface geology and morphology in support of the Coastal Sediment Availability and Flux (CSAF) Project. This dataset, Cedar_Island_2019_SBES_xyz.zip consists of single-beam horizontal position (x,y) and vertical (z) elevation data collected within the nearshore zone of Cedar Island. Additional survey and data details are available from the Coastal and Marine Geoscience Data System (CMGDS) at, https://cmgds.marine.usgs.gov/fan_info.php?fan=2019-332-FA.
For the single-beam bathymetry data, the differential positioning was obtained through post-processing the base station data to the rover.The bathymetry data were collected and processed in the World Geodetic System of 1984 (WGS84[G1762]) vertical and horizontal datums and were subsequently transformed using the National Oceanic and Atmospheric Administration's (NOAA) VDatum version 4.1 transformation software (https://vdatum.noaa.gov/) horizontally into the North American Datum of 1983 (NAD83 [2011]) and vertically into the North American Vertical Datum of 1988 (NAVD88) relative to the GEOID model of 2012B (GEOID12B).
20190809
20190815
ground condition
None planned
-75.615794
-75.537897
37.695914
37.570155
USGS Metadata Identifier
USGS:f867281e-a85e-42c3-a2fd-e2cd4d9e678d
Global Change Master Science Directory (GCMD)
OCEAN > COASTAL PROCESSES > BARRIER ISLANDS
OCEAN > COASTAL PROCESSES > BEACHES
DOI/USGS/CMG > COASTAL AND MARINE GEOLOGY, U.S. GEOLOGICAL SURVEY, U.S. DEPARTMENT OF INTERIOR
USGS Thesaurus
marine geology
marine geophysics
geophysics
bathymetry
single-beam echo sounder
ocean characteristics
ocean processes
ISO 19115 Topic Category
geoscientificinformation
elevation
oceans
location
imageryBaseMapsEarthCover
Geographic Names Information System
Wachapreague
Accomack County
Virginia
Atlantic Ocean
None
2019
None
Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. The U.S. Geological Survey requests to be acknowledged as originator of these data in future products or derivative research. These data should not be used for navigational purposes.
Chelsea A. Stalk
U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
Electronics Technician (Marine Iinstrumentation)
mailing and physical address
600 4th St. S
St. Petersburg
FL
33701
USA
727-502-8000
cstalk@usgs.gov
Funding and (or) support for this study were provided by the USGS Coastal and Marine Hazards and Resources Program, specifically the Costal Sediment Availability and Flux (CSAF) project. The authors would like to thank Nancy DeWitt and Arnell Forde of the USGS - St. Petersburg, Florida for their thoughtful peer reviews.
Environment as of Metadata Creation: Microsoft Windows 10 Version 1709 (Build 16299.666) Service Pack 1; Environmental Systems Research Institute (Esri) ArcGIS 10.6.0.8321
Arnell S. Forde
Chelsea A. Stalk
Jennifer L. Miselis
20200930
Archive of Chirp Subbottom Profile Data Collected in 2019 from Cedar Island, Virginia
Multimedia presentation
U.S. Geological Survey Data Release
doi:10.5066/P9S75Q0U
St. Petersburg, Florida
U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center
https://doi.org/10.5066/P9S75Q0U
The accuracy of the data is determined during data collection. This dataset is derived from a single survey using similar equipment, set-ups, and staff; therefore, the dataset is internally consistent. Methods are employed to maintain data collection consistency aboard the platforms. During mobilization, each piece of equipment was isolated to obtain internal and external offset measurements with respect to the survey platform. All the critical measurements were recorded manually and then digitally entered into their respective programs. Offsets between the single-beam transducers, motion reference units, and the global positioning system (GPS) antenna reference point (ARP) were measured and accounted for in post-processing. Differential Global Positioning System (DGPS) coordinates were obtained through post-processing using the software Online Positioning User Service (OPUS) maintained by the NOAA and the NGS , and Waypoint Product Group GrafNav, version 8.7.
These datasets are from one field activity with consistent instrument calibrations.
This data release contains single-beam horizontal position (x,y) and vertical (z) elevation data from August 2019, collected within nearshore waters of Cedar Island, Virginia. Users are advised to read the complete metadata record carefully for additional details.
All static base station sessions were processed through OPUS. The OPUS solutions were entered into a spreadsheet to compute a final, time-weighted position (latitude, longitude, and ellipsoid height) for the utilized base station. The time-weighted position for NGS benchmark AJ4587 (https://www.ngs.noaa.gov/cgi-bin/ds_mark.prl?PidBox=AJ4587) was calculated and used in subsequent processing steps. Accuracy pertaining to the base station coordinates utilized are as follows: Horizontal = +/- 0.00027 seconds (s) or approximately 0.003 meters (m).
All static base station sessions were processed through OPUS. The OPUS solutions were entered into a spreadsheet to compute a final, time-weighted position (latitude, longitude, and ellipsoid height) for the utilized base station. The time-weighted position for NGS benchmark AJ4587 (https://www.ngs.noaa.gov/cgi-bin/ds_mark.prl?PidBox=AJ4587) was calculated and used in subsequent processing steps (accuracy is computed to be +/- 0.006 m). The kinematic (rover) trajectories were processed using GrafNav version 8.70 software by Novatel, Inc. Due to GPS errors associated with a system failure at the time of acquisition, lines from survey day 222 (8/10/2019) utilized real-time navigation, and therefore during the quality control/quality assurance (QA/QC) processing step, some lines with known GPS issues were statically adjusted by the average crossing offset. The following lines have the associated vertical uncertainty, which should be considered before use (Line 0048_1731: -0.3826 m, 0049_1709_0001: -0.4578 m, 0050_1648: -0.4182 m, 0004_1930: +0.2767 m and Line 0001_1425: -0.2764 m). Transformed data have an additional reported vertical transformation error of 7.6158 centimeters (cm).
GPS Acquisition: One GPS base station was established on NGS benchmark AJ4587 (https://www.ngs.noaa.gov/cgi-bin/ds_mark.prl?PidBox=AJ4587), located within Seaside Park at the corner of Main Street and Atlantic Avenue, Wachapreague, VA. The base station was continually occupied and equipped with an Ashtech Proflex 800 GPS receiver recording 12-channel full-carrier-phase positioning signals (L1/L2) from satellites via Thales Choke-ring antennas, recording at a rate of 0.1 s.
2019
U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
Chelsea Stalk
Electronics Technician (Marine Instrumentation)
mailing and physical address
600 4th St. S
St. Petersburg
FL
33701
USA
727-502-8000
cstalk@usgs.gov
Single-Beam Bathymetry Acquisition: The single-beam bathymetric data were collected under USGS FAN 2019-332-FA and encompasses data from a single survey platform, a Chirp seismic sled, towed by the R/V Sallenger, a 26 ft fiberglass research vessel. A total of 299.075 line-km (62 lines) were surveyed. Boat motion was recorded at 50-millisecond (ms) intervals using an SBG motion sensor. HYPACK (version 18.1.8.0), 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 information to the boat operator aboard the R/V Sallenger. Depth soundings were recorded at 50-ms intervals using an Odom Echotrac CV100 echo sounder with a 200-kilohertz (kHz) 4-degree transducer. Data from the GPS receiver, motion sensor, and echo sounder 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 a single SonTek Castaway conductivity, temperature, and depth (CTD) instrument. The instrument was periodically cast overboard to observe changes in water column speed of sound (SOS). A total of 26 successful sound velocity casts were taken throughout the survey at an average depth of 3.99 m, and on average produced a sound velocity of 1519.08 meters per second (m/s).
2019
Chelsea A. Stalk
U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
Electronics Technician (Marine Instrumentation)
mailing and physical address
600 4th Street South
St. Petersburg
FL
33701
USA
(727) 502-8000
cstalk@usgs.gov
Differentially Corrected Navigation Processing: The coordinate value of the GPS base station is the time weighted average (TWA) of all current survey occupations. The base station coordinates were imported into GrafNav version 8.7 (Waypoint Product Group) and the kinematic GPS data from the survey platform were post-processed to the concurrent GPS session data at the base station. During processing, steps were taken to ensure that the trajectories between the base and the rover were clean, resulting in fixed positions. By analyzing the graphs, trajectory maps, and processing logs that GrafNav produces for each GPS session, GPS data from satellites flagged by the program as having poor health or satellite time segments that had cycle slips could be excluded, or the satellite elevation mask angle could be adjusted to improve the position solutions. The final differentially corrected, precise DGPS positions were computed at 0.1 s and exported in American Standard Code for Information Interchange (ASCII) text format. The GPS data were processed and exported in the WGS84 (G1762) geodetic datum.
2019
Chelsea A. Stalk
U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
Electronics Technician (Marine Instrumentation)
mailing and physical address
600 4th Street South
St. Petersburg
FL
33701
USA
(727) 502-8000
cstalk@usgs.gov
All bathymetry data were processed using CARIS HIPS and SIPS (Hydrographic Information Processing System and Sonar Information Processing System) version 11.2.3. The raw HYPACK data files were imported into CARIS, the differentially corrected navigation files were imported using the generic data parser (GDP) tool, and any SVP profile casts were entered and edited using the SVP editor. Lines from survey day 222 (8/10/2019) utilized real-time navigation due to GPS errors associated with a system failure. To utilize real-time navigation, the GPS heights were extracted from the raw Hypack (.RAW) files utilizing the CARIS command Line GUI (Version 2.0.4), and then written into an ASCII text file, which could be read by the GDP. Once GPS heights were applied using the GDP, a smoothing (moving average) filter of 60 seconds and a threshold of 1 was applied to data. The bathymetric data components (position, motion, depth, and SOS) for all data were then merged and geometrically corrected in CARIS to produce processed x,y,z data. Next, the data were edited for outliers and then further reviewed in the Subset Editor utility for crossing status, and questionable data points or areas. The geometrically corrected point data were then exported as an x,y,z ASCII text file referenced to WGS84 (G1762) ellipsoid height, in meters.
2019
U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
Chelsea A. Stalk
Electronics Technician (Marine Instrumentation)
mailing and physical
600 4th Street South
St. Petersburg
FL
33701
USA
(727) 502-8000
cstalk@usgs.gov
Quality Control, Quality Assurance (QA/QC): All single-beam data exported from CARIS were imported into Esri ArcMap version 10.6.0, where a shapefile of the individual sounding data points (x,y,z) was created and plotted in 0.25-m color coded intervals. First, all data were visually scanned for any obvious outliers or problems. Next, a track line shapefile was produced using X-tools Pro "Make Polylines from Points" function. Utilizing both the x,y,z (point) and track-line (polyline) shapefiles, an in house Python script evaluated elevation differences at the intersection of crossing track lines by calculating the elevation difference between points at each intersection using an inverse distance weighting equation with a search radius of 1 m. The root mean square error (RMSe) when crossing a track line it previously surveyed was 23.5 cm. Lines from survey day 222 (8/10/2019), which utilized real-time navigation, had crossing offsets that exceeded the published Odom CV100 instrument accuracy (1 cm +/- 0.7 percent depth) and therefore were statically (vertical) adjusted by the average crossing offset. The following vertical adjustments were made, Line 0048_1731: -0.3826 m, 0049_1709_0001: -0.4578 m, 0050_1648: -0.4182 m, 0004_1930: +0.2767 m and Line 0001_1425: -0.2764 m. Once these adjustments were made, the crossing program was run for a second time, which produced RMSe results of 19.86 cm crossing error, however 91% of all crossings are under 10 cm. The final adjusted file was exported from Esri ArcMap as an x,y,z text (.txt) file and made available in the download section of this data release, along with the populated track line shapefiles.
2019_332_CedarIsland_SBES_WGS84_UTM18N_Level_03_xyz.txt
2019
Cedar_Island_2019_SBES_WGS84_xyz.txt
Cedar_Island_2019_SBES_WGS84_Tracklines.shp
U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
Chelsea A. Stalk
Electronics Technician (Marine Instrumentation)
mailing and physical
600 4th Street South
St. Petersburg
FL
33701
USA
(727) 502-8000
cstalk@usgs.gov
Datum Transformation: NOAA's VDatum v.3.9 was used to transform single-beam data points (x,y,z) from their data acquisition datum (WGS84 [G1762]) to the NAD83 reference frame with NAVD88 elevations using the NGS geoid model 2012B (GEOID12B). For conversion from the WGS84 ellipsoid height to NAVD88 orthometric height, there is a total of 7.616 cm of uncertainty in the transformation (https://vdatum.noaa.gov/docs/est_uncertainties.html). Resultant data files have been made available in the downloads section of this data release.
Cedar_Island_2019_SBES_WGS84_xyz.txt
2019
Cedar_Island_2019_SBES_NAD83_NAVD88_G12B_xyz.txt
U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
Chelsea A. Stalk
Electronics Technician (Marine Instrumentation)
mailing and physical
600 4th Street South
St. Petersburg
FL
33701
USA
(727) 502-8000
cstalk@usgs.gov
Added keywords section with USGS persistent identifier as theme keyword.
20201013
U.S. Geological Survey
VeeAnn A. Cross
Marine Geologist
Mailing and Physical
384 Woods Hole Road
Woods Hole
MA
02543-1598
508-548-8700 x2251
508-457-2310
vatnipp@usgs.gov
Point
Point
480,440
Universal Transverse Mercator
18
0.999600
-75.000000
0.000000
500000.000000
0.000000
coordinate pair
0.6096
0.6096
meters
World Geodetic System of 1984
WGS_1984
6378137.000000
298.257222101
North American Vertical Datum 1988
0.01
meters
Attribute values
Cedar_Island_2019_SBES_WGS84_xyz.txt
Comma-delimited x,y,z file containing location, elevation, and date information pertaining to data collected on a towed chirp seismic sled, nearshore Cedar Island, Virginia in 2019.
U.S. Geological Survey
WGS84_UTM18N_X
WGS84 UTM x-axis coordinate (Zone 18N)
U.S. Geological Survey
445711.948
452499.796
meters
WGS84_UTM18N_Y
WGS84 UTM y-axis coordinate (Zone 18N)
U.S. Geological Survey
4158302.116
4172213.517
meters
Ellipsoid
Z-value (elevation) in WGS84, ellipsoid height
U.S. Geological Survey
-51.666
-38.831
meters
WGS84_Lat
WGS84 y-axis coordinate (latitude)
U.S. Geological Survey
37.570393
37.695743
Decimal Degrees
WGS84_Long
WGS84 x-axis coordinate (longitude)
U.S. Geological Survey
-75.614966
-75.53876
Decimal Degrees
Year
Calendar year of data acquisition
U.S. Geological Survey
2019
2019
DOY
Day of year of data acquisition
U.S. Geological Survey
221
226
UTC_Time
UTC time of data acquisition
U.S. Geological Survey
12:31:49.28
21:22:30.33
Hypack_Line
Line number and start of line UTC time.
HYPACK/U.S. Geological Survey
N/A
Cedar_Island_2019_SBES_NAD83_NAVD88_G12B_xyz.txt
Comma-delimited x,y,z file containing location, elevation, and date information.
U.S. Geological Survey
NAD83_UTM18N_X
NAD83 UTM x-axis coordinate (Zone 18N)
U.S. Geological Survey
445712.447
452500.294
meters
NAD83_ UTM18N_Y
NAD83 UTM y-axis coordinate (Zone 18N)
U.S. Geological Survey
4158301.151
4172212.549
meters
NAVD88_G12B
Z-value (elevation) in NAVD88 GEOID12B, orthometric height
U.S. Geological Survey
-13.583
-0.772
meters
NAD83_Lat
NAD83 y-axis coordinate (latitude)
U.S. Geological Survey
37.570393
37.695734
Decimal Degrees
NAD83_Long
NAD83 x-axis coordinate (longitude)
U.S. Geological Survey
-75.61496
-75.53876
Decimal Degrees
Year
Calendar year of data acquisition
U.S. Geological Survey
2019
2019
DOY
Day of year of data acquisition
U.S. Geological Survey
221
226
UTC_Time
UTC time of data acquisition
U.S. Geological Survey
12:31:49.28
21:22:30.33
Hypack_Line
Line number and start of line UTC time.
HYPACK/U.S. Geological Survey
N/A
Chelsea A. Stalk
U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
Electronics Technician (Marine Instrumentation)
mailing and physical address
600 4th Street South
St. Petersburg
FL
33701
USA
(727) 502-8000
cstalk@usgs.gov
Cedar_Island_2019_SBES_WGS84_xyz.txt, Cedar_Island_2019_SBES_NAD83_NAVD88_G12B_xyz.txt, Cedar_Island_2019_SBES_WGS84_Tracklines.shp
This digital publication was prepared by an agency of the United States Government. Although these data were processed successfully on a computer system at the U.S. Geological Survey, no warranty expressed or implied is made regarding the display or utility of the data on any other system, nor shall the act of distribution imply any such warranty. The U.S. Geological Survey shall not be held liable for improper or incorrect use of the data described and (or) contained herein. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof.
ASCII, Shapefile
ZIP
22.3
https://coastal.er.usgs.gov/data-release/doi-P927Q8M1/data/Cedar_Island_2019_SBES_xyz.zip
https://coastal.er.usgs.gov/data-release/doi-P927Q8M1/data/Cedar_Island_2019_SBES_Tracklines.zip
None
20201013
Chelsea A. Stalk
U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
Electronics Technician (Maine Instrumentation)
mailing and physical address
600 4th Street South
St. Petersburg
FL
33701
USA
(727) 502-8000
cstalk@usgs.gov
Content Standard for Digital Geospatial Metadata
FGDC-STD-001-1998