Chelsea A. Stalk
Jennifer L. Miselis
Nancy T. DeWitt
Billy J. Reynolds
20200215
Coastal Single-beam Bathymetry Data Collected in August 2018 from the Chandeleur Islands, Louisiana
U.S. Geological Survey Data Release
doi:10.5066/P9E6E79E
St. Petersburg, FL
St. Petersburg Coastal and Marine Science Center
https://doi.org/10.5066/P9E6E79E
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 the northern Chandeleur Islands, August 17-21, 2018. During this study, bathymetry data were collected aboard the research vessel (R/V) Jabba Jaw, a 21-foot (ft) twin hulled vessel outfitted with a single-beam echosounder.
To determine continued change to the shoreface morphology and evolution at the Chandeleur Islands, Louisiana, scientists from the USGS SPCMSC conducted a bathymetric survey of the Chandeleur Islands, during Field Activity Number (FAN) 2018-350-FA, sub FAN 18BIM02. This dataset, Chandeleur_2018_SBB_xyz.zip consists of single-beam horizontal position and vertical elevation data collected within the nearshore zone of the Chandeleur Islands, aboard a single research vessel. Additional survey and data details are available from CMGDS at, https://cmgds.marine.usgs.gov/fan_info.php?fan=2018-350-FA.
For the single-beam bathymetry data, the differential positioning was obtained through post-processing the base station data to the rover. This dataset, Chandeleur_2018_SBB_xyz.zip, was transformed from the initial World Geodetic System of 1984 (WGS84) G1762 datum to the North American Datum of 1983 (NAD83) North American Vertical Datum of 1988 (NAVD88), using the GEOID09 model (National Oceanic and Atmospheric Administration (NOAA) National Geodedic Survey (NGS) Transformation software VDatum, version 3.9 - http://vdatum.noaa.gov/).
20180817
20180821
ground condition
None planned
-88.916490
-88.761330
30.070269
29.867649
USGS Metadata Identifier
USGS:71988c22-5244-4d0c-87f6-31590c6fbd1a
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
Chandeleur Islands
Chandeleur Sound
Hewes Point
Louisiana
Gulf of Mexico
United States of America
None
2018
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
Cherokee Nation Technologies/U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
Researcher III
mailing and physical address
600 4th St. S
St. Petersburg
FL
33701
USA
727-502-8000
cstalk@contractor.usgs.gov
Funding and (or) support for this study were provided by the USGS Coastal and Marine Hazards and Resources Program. The authors would like to thank Andrew Farmer 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
The accuracy of the data is determined during data collection. This dataset is derived from a single field 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 Ashtech antenna reference point (ARP) were measured and accounted for in post-processing. Differential Global Positioning System (DGPS) coordinates were obtained through post-processing using specific software packages (NGS Online Positioning User Service (OPUS), and Waypoint Product Group GrafNav, version 8.7).
These datasets are from one field activity with consistent instrument calibrations.
This data release contains horizontal position and vertical elevation x,y,z single-beam data from August 2018, collected within nearshore waters of the Chandeleur Islands, Louisiana. Users are advised to read the complete metadata record carefully for additional details.
All static base station sessions were processed through the OPUS maintained by the NOAA and the NGS. 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 USGS benchmark MRK3 was calculated and used in subsequent processing steps. Accuracy pertaining to the base station coordinates utilized are as follows: Horizontal = +/- 0.00017 seconds (s).
All static base station sessions were processed through OPUS maintained by NOAA and NGS. 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 USGS benchmark MRK3 was calculated and used in subsequent processing steps (accuracy is computed to be +/- 0.0098 meters [m]). The kinematic (rover) trajectories were processed using GrafNav version 8.70 software by Novatel, Inc. In addition, total propagated uncertainty (TPU) values accompany each xyz data point and are a result of calculations performed in hydrographic processing software CARIS (Version 11.0.7). Transformed data have an additional reported vertical transformation error of 7.6158 centimeters (cm).
GPS Acquisition: One Geographic Positioning System (GPS) base station was established on USGS benchmark MRK3, located within the northern portion of the Chandeleur Islands. 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.
2018
U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
Billy J. Reynolds
Engineering Technician
mailing and physical address
600 4th St. S
St. Petersburg
FL
33701
USA
727-502-8067
727-502-8181
breynolds@usgs.gov
Single-Beam Bathymetry Acquisition: The single-beam bathymetric data were collected under USGS FAN 2018-350-FA and encompasses data from a single survey platform, the RV Jabba Jaw, a 21 ft shallow draft center console catamaran (18BIM02), which surveyed a total of 143.726 line-km (66 lines). Boat motion was recorded at 50-millisecond (ms) intervals using a TSS 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. Depth soundings were recorded at 50-ms intervals using an Odom echotrac CV100 sounder with a 200-kilohertz (kHz) transducer. Data from the GPS receiver, motion sensor, and fathometer were recorded in real-time aboard the vessel independently 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 44 successful sound velocity casts were taken throughout the survey at an average depth of 4.47 m, and on average produced a sound velocity of 1537.12 meters per second (m/s).
2018
Chelsea A. Stalk
Cherokee Nation Technologies/U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
Researcher III
mailing and physical address
600 4th Street South
St. Petersburg
FL
33701
USA
(727) 502-8000
cstalk@contractor.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 vessels 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. Concurrent post-processed navigation data to single-beam data points replace the uncorrected rover positions, recorded during acquisition, in subsequent processing steps. The GPS data were processed and exported in the WGS84 (G1762) geodetic datum.
2018
Chelsea A. Stalk
Cherokee Nation Technologies/U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
Researcher III
mailing and physical address
600 4th Street South
St. Petersburg
FL
33701
USA
(727) 502-8000
cstalk@contractor.usgs.gov
All data were processed using CARIS HIPS and SIPS (Hydrographic Information Processing System and Sonar Information Processing System) version 11.0.7. The raw HYPACK data files were imported into CARIS, the differentially corrected navigation files were imported using the generic data parser tool, and any SVP profile casts were entered and edited using the SVP editor. The bathymetric data components (position, motion, depth, and SOS) were then merged and geometrically corrected in CARIS to produce processed xyz data. TSS Motion Reference Unit (MRU) malfunction on Day 229 was corrected by applying a 90-degree offset to all effected data. Data associated with the correction are computed to have unreasonably high TPU values due to the applied offset. 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 xyz ASCII text file referenced to WGS84 (G1762), ellipsoid height in meters.
2018
Cherokee Nation Technologies/U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
Chelsea A. Stalk
Researcher III
mailing and physical
600 4th Street South
St. Petersburg
FL
33701
USA
(727) 502-8000
cstalk@contractor.usgs.gov
Quality Control, Quality Assurance (QA/QC) and Uncertainty Analysis: All single-beam data exported from CARIS, and elevation data exported from GrafNav were imported into Esri ArcMap version 10.6.0, where a shapefile of the individual sounding data points (xyz) 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 trackline shapefile was produced using X-tools Pro "Make Polylines from Points" function for each survey platform. Utilizing both the xyz (point) and trackline (polyline) shapefiles, a Python script evaluated 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 1 m. The root mean square error (RMSe) when crossing a trackline it previously surveyed was 11.79 cm. Since the bias between elevations was on the order of the Odom CV100 instrument accuracy (1 cm +/- 0.7 percent depth), no adjustments were made. These merged files were exported from Esri ArcMap as an xyz text (.txt) file and made available in the download section of this data release, along with the populated trackline shapefiles.
18BIM02_SBB_Level_03_P9E6E79_WGS84_UTM16N.txt
2018
Chandeleur_Islands_2018_SBB_WGS84_xyz.txt
Chandeleur_Islands_2018_SBB_WGS84_Tracklines.shp
Cherokee Nation Technologies/U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
Chelsea A. Stalk
Researcher III
mailing and physical
600 4th Street South
St. Petersburg
FL
33701
USA
(727) 502-8000
cstalk@contractor.usgs.gov
Datum Transformation: NOAA's VDatum v.3.9 was used to transform single-beam and GPS elevation data points (xyz) from their data acquisition datum (WGS84 G1762) to the NAD83 reference frame with NAVD88 elevations using the NGS geoid model of 2009 (GEOID09). For conversion from the WGS84 ellipsoid to NAVD88, there is a total of 7.616 cm of uncertainty in the transformation (http://vdatum.noaa.gov/docs/est uncertainties.html). Resultant data files have been made available in the downloads section of this data release.
Chandeleur_Islands_2018_SBB_WGS84_xyz.txt
2018
Chandeleur_Islands_2018_SBB_NAD83_NAVD88_G09.txt
Cherokee Nation Technologies/U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
Chelsea A. Stalk
Researcher III
mailing and physical
600 4th Street South
St. Petersburg
FL
33701
USA
(727) 502-8000
cstalk@contractor.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
687,423
Universal Transverse Mercator
16
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
Chandeleur_Islands_2018_SBB_WGS84_xyz.txt
Comma-delimited xyz file and Esri shapefile containing location, elevation, and date information pertaining to data collected aboard the RV Jabba Jaw in 2018, nearshore the Chandeleur Islands, Louisiana.
U.S. Geological Survey
WGS84_X
WGS84 UTM x-axis coordinate (Zone 16N)
U.S. Geological Survey
315268.074
329888.846
meters
WGS84_Y
WGS84 UTM y-axis coordinate (Zone 16N)
U.S. Geological Survey
3305655.75
3327884.757
meters
Ellipsoid
Z-value (elevation) in WGS84 ellipsoid heights
U.S. Geological Survey
-41.599
-28.078
meters
Year
Calendar year of data acquisition
U.S. Geological Survey
2018
2018
meters
DOY
Day of year of data acquisition
U.S. Geological Survey
229
233
Time
UTC time of data acquisition
U.S. Geological Survey
15:57:45.039
22:05:33.578
Hypack_Line
ub-FAN identifier followed by platform name abbreviation, line number and start of line UTC time.
HYPACK/U.S. Geological Survey
N/A
Depth_TPU
Total propagated uncertainty value as calculated by CARIS software, in meters.
U.S. Geological Survey
0.125
5.387
Chandeleur_Islands_2018_SBB_NAD83_NAVD88_G09.txt
Comma-delimited xyz file containing location, elevation, and date information.
U.S. Geological Survey
NAD83_X
NAD83 UTM x-axis coordinate (Zone 16N)
U.S. Geological Survey
315268.86299
329889.63131
meters
NAD83_Y
NAD83 UTM y-axis coordinate (Zone 16N)
U.S. Geological Survey
3305655.13157
3327884.1338
meters
NAVD88_G09
Z-value (elevation) in NAVD88 GEOID 09
U.S. Geological Survey
-13.66214
-0.50582
meters
Year
Calendar year of data acquisition
U.S. Geological Survey
2018
2018
meters
DOY
Day of year of data acquisition
U.S. Geological Survey
229
233
UTC_Time
UTC time of data acquisition
U.S. Geological Survey
15:57:45.039
22:05:33.578
Hypack_Line
Sub-FAN identifier followed by platform name abbreviation, line number and start of line UTC time.
HYPACK/U.S. Geological Survey
N/A
Depth_TPU
Total Propagated uncertainty value as calculated by CARIS software measures in meters.
U.S. Geological Survey
0.130
5.387
Chelsea A. Stalk
Cherokee Nation Technologies/U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
Researcher III
mailing and physical address
600 4th Street South
St. Petersburg
FL
33701
USA
(727) 502-8000
cstalk@contractor.usgs.gov
Chandeleur_Islands_2018_SBB_WGS84_xyz.txt, Chandeleur_Islands_2018_SBB_NAD83_NAVD88_G09.txt, Chandeleur_Islands_2018_SBB_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
ZIP
25.3
https://coastal.er.usgs.gov/data-release/doi-P9E6E79/data/Chandeleur_Islands_2018_SBB_xyz.zip
https://coastal.er.usgs.gov/data-release/doi-P9E6E79/data/Chandeleur_Islands_2018_SBB_Tracklines.zip
None
20201013
Chelsea A. Stalk
Cherokee Nation Technologies/U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
Researcher III
mailing and physical address
600 4th Street South
St. Petersburg
FL
33701
USA
(727) 502-8000
cstalk@contractor.usgs.gov
Content Standard for Digital Geospatial Metadata
FGDC-STD-001-1998