Single Beam Bathymetry XYZ Data Collected in July 2015 from Point Au Fer to Raccoon Point, Louisiana

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Frequently anticipated questions:


What does this data set describe?

Title:
Single Beam Bathymetry XYZ Data Collected in July 2015 from Point Au Fer to Raccoon Point, Louisiana
Abstract:
As part of the Barrier Island Comprehensive Monitoring Program (BICM), scientists from the U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted a nearshore single-beam bathymetry survey along the south-central coast of Louisiana, from Raccoon Point to Point Au Fer Island, in July 2015. The goal of the BICM program is to provide long-term data on Louisiana’s coastline and use this data to plan, design, evaluate, and maintain current and future barrier island restoration projects. The data described in this report will provide baseline bathymetric information for future research investigating island evolution, sediment transport, and recent and long term geomorphic change, and will support modeling of future changes in response to restoration and storm impacts. The survey area encompasses more than 300 square kilometers (km2) of nearshore environment from Raccoon Point to Point Au Fer Island. This data series serves as an archive of processed single-beam bathymetry data, collected from July 22–29, 2015, under USGS Field Activity Number 2015-320-FA. Geographic information system data products include a 200-meter-cell-size interpolated bathymetry grid, trackline maps, and point data files.
Supplemental_Information:
For the single beam bathymetry, the differential positioning was obtained through post processing the base station data to the rover data. This dataset was transformed from the initial datum International Terrestrial Reference Frame of 2000 (ITRF00) to the North American Datum of 1983 (NAD93) (CORS 96), using the geoid model of 2012A (GEOID12A) (National Oceanic and Atmospheric Administration National Geodetic Survey [NOAA NGS] VDatum software version 3.2; http://vdatum.noaa.gov/). The final x,y,z position data were gridded at a 200-meter cell size resolution to create the digital elevation model, which is also included in this Data Series.
  1. How might this data set be cited?
    U.S. Geological Survey, 2017, Single Beam Bathymetry XYZ Data Collected in July 2015 from Point Au Fer to Raccoon Point, Louisiana:.

    Online Links:

    This is part of the following larger work.

    Stalk, Chelsea A., DeWitt, Nancy T., Kindinger, Jack L., Flocks, James G., Reynolds, Billy J., Kelso, Kyle W., Fredericks, Jake J., and Tuten, Thomas M., 2017, Coastal Single-Beam Bathymetry Data Collected in 2015 from Raccoon Point to Point Au Fer, Louisiana: U.S. Geological Survey Data Series 1041, U.S. Geological Survey, St. Petersburg, Florida.

    Online Links:

  2. What geographic area does the data set cover?
    West_Bounding_Coordinate: -91.393528
    East_Bounding_Coordinate: -90.843372
    North_Bounding_Coordinate: 29.333489
    South_Bounding_Coordinate: 29.055925
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
    Beginning_Date: 22-Jul-2015
    Ending_Date: 29-Jul-2015
    Currentness_Reference:
    data collection interval
  5. What is the general form of this data set?
    Geospatial_Data_Presentation_Form: ASCII digital data
  6. How does the data set represent geographic features?
    1. How are geographic features stored in the data set?
    2. What coordinate system is used to represent geographic features?
  7. How does the data set describe geographic features?

Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
    • U.S. Geological Survey
  2. Who also contributed to the data set?
    U.S. Geological Survey, Coastal and Marine Geology Program, St. Petersburg Coastal and Marine Science Center (SPCMSC).
  3. To whom should users address questions about the data?
    Chelsea A. Stalk
    Cherokee Nation Technologies/U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
    Researcher I
    600 4th Street South
    St. Petersburg, FL
    USA

    (727)502-8000 (voice)
    cstalk@usgs.gov

Why was the data set created?

This zip archive contains processed x,y,z data points for all single beam bathymetry data collected under the FAN 2015-320-FA, which encompasses data from four separate survey platforms; the R/V Sallenger (15BIM05), R/V Jabba Jaw (15BIM06), R/V Shark (15BIM07), and R/V Chum (15BIM08), all part of the July 2015 Point Au Fer survey.

How was the data set created?

  1. From what previous works were the data drawn?
  2. How were the data generated, processed, and modified?
    Date: 2015 (process 1 of 6)
    GPS Acquisition: GPS Acquisition: The Geographic Positioning Systems (GPS) base stations were established by USGS personnel for the purpose of this survey. Benchmarks Point Au Fer One (PAF1), was located to the east of the survey area on a marsh island to the west of Fish Bayou, Point Au Fer Two (PAF2) was located in the middle of the survey area on the eastern shore of Oyster Bayou, and the final benchmark, Point au Fer Three (PAF3), was located in the western portion of the survey on the middle shore of Point Au Fer Island (http://pubs.usgs.gov/ds/01041/html/ds1041_ overview.html). All base stations were occupied for 24 hours and equipped with Ashtech Proflex GPS Receivers recording 12-channel full-carrier-phase positioning signals (L1/L2) from satellites via Thales Choke-ring antennas, recording at a rate of 0.1 seconds (s). Person who carried out this activity:
    Chelsea A. Stalk
    Cherokee Nation Technologies/U.S. Geological Survey's St. Petersburg Coastal and Marine Science Center
    Researcher I
    600 4th Street South
    St. Petersburg, FL
    USA

    (727) 502-8000 (voice)
    cstalk@usgs.gov
    Date: 2015 (process 2 of 6)
    Single Beam Bathymetry Acquisition: The single beam bathymetric data were collected under the FAN 2015-320-FA, which encompasses four sub-cruise identifiers specific to platform (15BIM05, 15BIM06, 15BIM07, 15BIM08). The R/V Sallenger (15BIM05), a 26-foot (ft) Parker, collected 307.7 line-km (70 Lines), R/V Jabba Jaw (15BIM06), a shallow draft 22-ft Twin Vee collected 164 line-km (34 lines), the R/V Shark (15BIM07), a 12-ft Yamaha Personal Water Craft (PWC) collected 246.7 line-km (72 lines), and the R/V Chum (15BIM08), an additional 12-ft Yamaha PWC collected 392.2 line-km (123 lines) of single beam XYZ point data. Boat motion was recorded at 50-millisecond (ms) intervals using a Teledyne TSS Dynamic Motion Sensor (TSS DMS-05) only on vessels 15BIM05 and 15BIM06. A motion sensor devise was not used for either PWC (15BIM06, 15BM07). Rather, to minimalize motion errors, both R/V Shark and R/V Chum recorded GPS at a rapid rate of 0.1s, utilized a short antenna height by use of a lever arm, and were outfitted with a narrow (4 degree) transducer beam. HYPACK version 14.0.9.47, 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 all vessels 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 UTC. Sound velocity profile (SVP) measurements were collected using two SonTek Castaway Conductivity, Temperature, and Depth (CTD) instruments as well as one Valport mini SVP. The instruments were periodically cast overboard to observe changes in water column speed of sound (SOS). A total of 35 successful sound velocity casts were taken throughout the survey at an average depth of 1.58 meters, and on average produced a sound velocity of 1532.57 meters per second (m/s). Person who carried out this activity:
    Chelsea A. Stalk
    Cherokee Nation Technologies/U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
    Researcher I
    600 4th Street South
    St. Petersburg, FL
    USA

    (727) 502-8000 (voice)
    cstalk@usgs.gov
    Data sources produced in this process:
    • HYPACK raw (*.RAW) data files for each trackline surveyed. HYPACK target files for any targets (*.TGT) recorded digitally while surveying, speed of sound files (*.TXT) in text format.
    Date: 2015 (process 3 of 6)
    Differentially Corrected Navigation Processing: The coordinate values of the GPS base stations (PAF1, PAF2, PAF3) are the time-weighted average of values obtained from OPUS. The base station coordinates were imported into GrafNav version 8.5 (Waypoint Product Group) and the kinematic GPS data from the survey vessel were post processed to the concurrent GPS session data at the base stations. 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 the respective time intervals of the roving GPS (0.2 s for 15BIM05, 15BIM06 and 0.1 s for 15BIM07, 15BIM08) and exported in ASCII text format to replace the uncorrected rover positions recorded during acquisition. The GPS data were processed and exported in the World Geodetic System of 1984 (WGS84 G1150) geodetic datum. Person who carried out this activity:
    Cherokee Nation Technologies/U.S. Geological Survey
    Attn: Chelsea A. Stalk
    Researcher I
    600 4th Street South
    St. Petersburg, FL
    USA

    (727) 502-8000 (voice)
    cstalk@usgs.gov
    Data sources produced in this process:
    • Post-processed differential navigation data for the rover (boat) in ASCII text format. Three files (forward, reverse, and combined trajectories) are produced for each GPS session file.
    Date: 2015 (process 4 of 6)
    Single beam bathymetry processing: All data were processed using CARIS HIPS and SIPS (Hydrographic Information Processing System and Sonar Information Processing System) version 9.0.17. The raw HYPACK (version 14.0.9.47 for 15BIM05, 15BIM06 and version 13.0.09.17 for 15BIM07 and 15BIM08, respectively) data files were imported into CARIS, the differentially corrected navigation files were imported using the generic data parser tool within CARIS, and any SVP profile casts were entered and edited using the SVP editor within CARIS. The bathymetric data components (position, motion, depth, and SOS) 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 (G1150), equivalent to ITRF00, and ellipsoid height in meters. Person who carried out this activity:
    Cherokee Nation Technologies/U.S. Geological Survey
    Attn: Chelsea A. Stalk
    Researcher I
    600 4th Street South
    St. Petersburg, FL
    USA

    (727) 502-8000 (voice)
    cstalk@usgs.gov
    Data sources used in this process:
    • Post-processed differential navigation data, raw HYPACK bathymetric data, and sound velocity data all in ASCII text format.
    Data sources produced in this process:
    • 15BIM05_SBB_Level_02_1041_ITRF00.txt 15BIM06_SBB_Level_02_1041_ITRF00.txt 15BIM07_SBB_Level_02_1041_ITRF00.txt 15BIM08_SBB_Level_02_1041_ITRF00.txt
    Date: 2015 (process 5 of 6)
    Quality Control and Quality Assurance (QA/QC) and Datum transformation: All single beam data found in the ASCII files exported from CARIS were imported into Esri ArcMap version 10.2, where a shapefile of the individual data points (x,y,z) was created and plotted in 1-m color coded intervals. First, all data were visually scanned for any obvious outliers or problems. A Python script was used for the purpose of evaluating elevation differences at the intersection of crossing tracklines by calculating the elevation difference between points at each intersection using an inverse distance weighting equation. GPS cycle slips, stormy weather conditions, and rough sea surface states can contribute to poor data quality. If discrepancies that exceed the acceptable error threshold were found, then the line in error was either removed or statically adjusted by the average of the crossings within the line. The script was run on all vessel point data first on a vessel by vessel basis and then run a final time for all data points from all vessels collectively. For this dataset, the collective run, using a merged shapefile of all vessel point data, is the most important as the survey structure did not allow for sufficient vessel crossing, rather vessels crossing other vessels. Once the dataset passed all QA/QC procedures and manual editing steps, the data were considered final and included in the download files, provided in this Data Series. Person who carried out this activity:
    Cherokee Nation Technologies/U.S. Geological Survey
    Attn: Chelsea A. Stalk
    Researcher I
    600 4th Street South
    St. Petersburg, FL
    USA

    (727) 502-8000 (voice)
    cstalk@usgs.gov
    Data sources used in this process:
    • 15BIM05_SBB_Level_02_1041_ITRF00.txt 15BIM06_SBB_Level_02_1041_ITRF00.txt 15BIM07_SBB_Level_02_1041_ITRF00.txt 15BIM08_SBB_Level_02_1041_ITRF00.txt
    Data sources produced in this process:
    • 15BIM05_SBB_Level_03_1041_ITRF00.txt 15BIM06_SBB_Level_03_1041_ITRF00.txt 15BIM07_SBB_Level_03_1041_ITRF00.txt 15BIM08_SBB_Level_03_1041_ITRF00.txt
    Date: 2015 (process 6 of 6)
    Datum Transformation: Person who carried out this activity:
    Cherokee Nation Technologies/U.S. Geological Survey
    Attn: Chelsea A. Stalk
    Researcher I
    600 4th Street South
    St. Petersburg, FL
    USA

    (727) 502-8000 (voice)
    cstalk@usgs.gov Detailed_Description Entity_Type Entity_Type_Label 15BIM05_SBB_Level_03_1041_ITRF00.txt Entity_Type_Definition ASCII text files containing the processed single beam bathymetry x,y,z data in the native format of WGS84 (ITRF00) Ellipsoid Height. Entity_Type_Definition_Source OPUS Attribute Attribute_Label ITRF00_Y Attribute_Definition WGS84 (ITRF00) Y-coordinate (northing) of sample point, in meters. Attribute_Definition_Source OPUS Attribute_Domain_Values Range_Domain Range_Domain_Minimum 3216570.463 Range_Domain_Maximum 3245261.836 Attribute_Measurement_Resolution 0.0001 Attribute Attribute_Label ITRF00_X Attribute_Definition WGS84 (ITRF00) X-coordinate (easting) of sample point, in meters. Attribute_Definition_Source OPUS Attribute_Domain_Values Range_Domain Range_Domain_Minimum 656697.855 Range_Domain_Maximum 709418.424 Attribute_Measurement_Resolution 0.0001 Attribute Attribute_Label ELLIPSOID_HEIGHT Attribute_Definition Ellipsoid height of sample point, in meters. Attribute_Definition_Source OPUS Attribute_Domain_Values Range_Domain Range_Domain_Minimum -34.751 Range_Domain_Maximum -27.008 Attribute_Measurement_Resolution 0.0001 Detailed_Description Entity_Type Entity_Type_Label 15BIM06_SBB_Level_03_1041_ITRF00.txt Entity_Type_Definition ASCII text files containing the processed single beam bathymetry x,y,z data in the native format of WGS84 (ITRF00) Ellipsoid Height. Entity_Type_Definition_Source OPUS Attribute Attribute_Label ITRF00_Y Attribute_Definition WGS84 (ITRF00) Y-coordinate (northing) of sample point, in meters. Attribute_Definition_Source OPUS Attribute_Domain_Values Range_Domain Range_Domain_Minimum 3227287.870 Range_Domain_Maximum 3246011.773 Attribute_Measurement_Resolution 0.0001 Attribute Attribute_Label ITRF00_X Attribute_Definition WGS84 (ITRF00) X-coordinate (easting) of sample point, in meters. Attribute_Definition_Source OPUS Attribute_Domain_Values Range_Domain Range_Domain_Minimum 656384.57 Range_Domain_Maximum 685500.769 Attribute_Measurement_Resolution 0.0001 Attribute Attribute_Label ELLIPSOID_HEIGHT Attribute_Definition Ellipsoid height of sample point, in meters. Attribute_Definition_Source OPUS Attribute_Domain_Values Range_Domain Range_Domain_Minimum -29.613 Range_Domain_Maximum -26.764 Attribute_Measurement_Resolution 0.0001 Detailed_Description Entity_Type Entity_Type_Label 15BIM07_SBB_Level_03_1041_ITRF00.txt Entity_Type_Definition ASCII text files containing the processed single beam bathymetry x,y,z data in the native format of WGS84 (ITRF00) Ellipsoid Height. Entity_Type_Definition_Source OPUS Attribute Attribute_Label ITRF00_Y Attribute_Definition WGS84 (ITRF00) Y-coordinate (northing) of sample point, in meters. Attribute_Definition_Source OPUS Attribute_Domain_Values Range_Domain Range_Domain_Minimum 3216091.930 Range_Domain_Maximum 3246058.729 Attribute_Measurement_Resolution 0.0001 Attribute Attribute_Label ITRF00_X Attribute_Definition WGS84 (ITRF00) X-coordinate (easting) of sample point, in meters. Attribute_Definition_Source OPUS Attribute_Domain_Values Range_Domain Range_Domain_Minimum 661335.168 Range_Domain_Maximum 708742.400 Attribute_Measurement_Resolution 0.0001 Attribute Attribute_Label ELLIPSOID_HEIGHT Attribute_Definition Ellipsoid height of sample point, in meters. Attribute_Definition_Source OPUS Attribute_Domain_Values Range_Domain Range_Domain_Minimum -30.047 Range_Domain_Maximum -26.107 Attribute_Measurement_Resolution 0.0001 Detailed_Description Entity_Type Entity_Type_Label 15BIM08_SBB_Level_03_1041_ITRF00.txt Entity_Type_Definition ASCII text files containing the processed single beam bathymetry x,y,z data in the native format of WGS84 (ITRF00) Ellipsoid Height. Entity_Type_Definition_Source OPUS Attribute Attribute_Label ITRF00_Y Attribute_Definition WGS84 (ITRF00) Y-coordinate (northing) of sample point, in meters. Attribute_Definition_Source OPUS Attribute_Domain_Values Range_Domain Range_Domain_Minimum 3216138.519 Range_Domain_Maximum 3245405.535 Attribute_Measurement_Resolution 0.0001 Attribute Attribute_Label ITRF00_X Attribute_Definition WGS84 (ITRF00) X-coordinate (easting) of sample point, in meters. Attribute_Definition_Source OPUS Attribute_Domain_Values Range_Domain Range_Domain_Minimum 658827.007 Range_Domain_Maximum 709213.048 Attribute_Measurement_Resolution 0.0001 Attribute Attribute_Label ELLIPSOID_HEIGHT Attribute_Definition Ellipsoid height of sample point, in meters. Attribute_Definition_Source OPUS Attribute_Domain_Values Range_Domain Range_Domain_Minimum -29.97 Range_Domain_Maximum -26.215 Attribute_Measurement_Resolution 0.0001 Detailed_Description Entity_Type Entity_Type_Label 15BIM05_SBB_03_1041_NAD83_UTM15N_NAVD88_GEOID12A.txt Entity_Type_Definition ASCII text files containing the processed single beam bathymetry x,y,z data transformed to the North American Datum of 1983 (NAD83) geodetic datum and North American Vertical Datum of 1988 (NAVD88) orthometric height, derived using the GEOID12A model. Entity_Type_Definition_Source USGS Attribute Attribute_Label NAD83_Y Attribute_Definition NAD83 (CORS96) Y-coordinate (northing) of sample point, in meters. Attribute_Definition_Source VDatum version 3.2 Attribute_Domain_Values Range_Domain Range_Domain_Minimum 3216569.949 Range_Domain_Maximum 3245261.318 Attribute_Measurement_Resolution 0.0001 Attribute Attribute_Label NAD83_X Attribute_Definition NAD83 (CORS96) X-coordinate (easting) of sample point, in meters. Attribute_Definition_Source VDatum version 3.2 Attribute_Domain_Values Range_Domain Range_Domain_Minimum 656698.695 Range_Domain_Maximum 709419.251 Attribute_Measurement_Resolution 0.0001 Attribute Attribute_Label GEOID12A Attribute_Definition NAVD88 (orthometric height) of sample point, in meters with respect to GEOID12A. Attribute_Definition_Source VDatum version 3.2 Attribute_Domain_Values Range_Domain Range_Domain_Minimum -9.034 Range_Domain_Maximum -1.167 Attribute_Measurement_Resolution 0.0001 Detailed_Description Entity_Type Entity_Type_Label 15BIM06_SBB_03_1041_NAD83_UTM15N_NAVD88_GEOID12A.txt Entity_Type_Definition ASCII text files containing the processed single beam bathymetry x,y,z data transformed to the North American Datum of 1983 (NAD83) geodetic datum and North American Vertical Datum of 1988 (NAVD88) orthometric height, derived using the GEOID12A model. Entity_Type_Definition_Source USGS Attribute Attribute_Label NAD83_Y Attribute_Definition NAD83 (CORS96) Y-coordinate (northing) of sample point, in meters. Attribute_Definition_Source VDatum version 3.2 Attribute_Domain_Values Range_Domain Range_Domain_Minimum 3227287.355 Range_Domain_Maximum 3246011.255 Attribute_Measurement_Resolution 0.0001 Attribute Attribute_Label NAD83_X Attribute_Definition NAD83 (CORS96) X-coordinate (easting) of sample point, in meters. Attribute_Definition_Source VDatum version 3.2 Attribute_Domain_Values Range_Domain Range_Domain_Minimum 656385.410 Range_Domain_Maximum 685501.6022 Attribute_Measurement_Resolution 0.0001 Attribute Attribute_Label GEOID12A Attribute_Definition NAVD88 (orthometric height) of sample point, in meters with respect to GEOID12A. Attribute_Definition_Source VDatum version 3.2 Attribute_Domain_Values Range_Domain Range_Domain_Minimum -3.603 Range_Domain_Maximum -0.582 Attribute_Measurement_Resolution 0.0001 Detailed_Description Entity_Type Entity_Type_Label 15BIM07_SBB_03_1041_NAD83_UTM15N_NAVD88_GEOID12A.txt Entity_Type_Definition ASCII text files containing the processed single beam bathymetry x,y,z data transformed to the North American Datum of 1983 (NAD83) geodetic datum and North American Vertical Datum of 1988 (NAVD88) orthometric height, derived using the GEOID12A model. Entity_Type_Definition_Source USGS Attribute Attribute_Label NAD83_Y Attribute_Definition NAD83 (CORS96) Y-coordinate (northing) of sample point, in meters. Attribute_Definition_Source VDatum version 3.2 Attribute_Domain_Values Range_Domain Range_Domain_Minimum 3216091.416 Range_Domain_Maximum 3243058.212 Attribute_Measurement_Resolution 0.0001 Attribute Attribute_Label NAD83_X Attribute_Definition NAD83 (CORS96) X-coordinate (easting) of sample point, in meters. Attribute_Definition_Source VDatum version 3.2 Attribute_Domain_Values Range_Domain Range_Domain_Minimum 661336.007 Range_Domain_Maximum 708743.228 Attribute_Measurement_Resolution 0.0001 Attribute Attribute_Label GEOID12A Attribute_Definition NAVD88 (orthometric height) of sample point, in meters with respect to GEOID12A. Attribute_Definition_Source VDatum version 3.2 Attribute_Domain_Values Range_Domain Range_Domain_Minimum -7.762 Range_Domain_Maximum -0.200 Attribute_Measurement_Resolution 0.0001 Detailed_Description Entity_Type Entity_Type_Label 15BIM08_SBB_03_1041_NAD83_UTM15N_NAVD88_GEOID12A.txt Entity_Type_Definition ASCII text files containing the processed single beam bathymetry x,y,z data transformed to the North American Datum of 1983 (NAD83) geodetic datum and North American Vertical Datum of 1988 (NAVD88) orthometric height, derived using the GEOID12A model. Entity_Type_Definition_Source USGS Attribute Attribute_Label NAD83_Y Attribute_Definition NAD83 (CORS96) Y-coordinate (northing) of sample point, in meters. Attribute_Definition_Source VDatum version 3.2 Attribute_Domain_Values Range_Domain Range_Domain_Minimum 3216138.005 Range_Domain_Maximum 3245405.017 Attribute_Measurement_Resolution 0.0001 Attribute Attribute_Label NAD83_X Attribute_Definition NAD83 (CORS96) X-coordinate (easting) of sample point, in meters. Attribute_Definition_Source VDatum version 3.2 Attribute_Domain_Values Range_Domain Range_Domain_Minimum 658827.846 Range_Domain_Maximum 709213.876 Attribute_Measurement_Resolution 0.0001 Attribute Attribute_Label GEOID12A Attribute_Definition NAVD88 (orthometric height) of sample point, in meters with respect to GEOID12A. Attribute_Definition_Source VDatum version 3.2 Attribute_Domain_Values Range_Domain Range_Domain_Minimum -9.362 Range_Domain_Maximum -0.401 Attribute_Measurement_Resolution 0.0001
    Data sources used in this process:
    • 15BIM05_SBB_Level_03_1041_ITRF00.txt 15BIM06_SBB_Level_03_1041_ITRF00.txt 15BIM07_SBB_Level_03_1041_ITRF00.txt 15BIM08_SBB_Level_03_1041_ITRF00.txt
    Data sources produced in this process:
    • 15BIM05_SBB_Level_03_1041_NAD83_NAVD88_Geoid12A.txt 15BIM06_SBB_Level_03_1041_NAD83_NAVD88_Geoid12A.txt 15BIM07_SBB_Level_03_1041_NAD83_NAVD88_Geoid12A.txt 15BIM08_SBB_Level_03_1041_NAD83_NAVD88_Geoid12A.txt
  3. What similar or related data should the user be aware of?

How reliable are the data; what problems remain in the data set?

  1. How well have the observations been checked?
    The accuracy of the data is determined during data collection. This dataset is from one research cruise and is therefore internally consistent. Methods are employed to maintain data collection consistency aboard all platforms (15BIM05, 15BIM06, 15BIM07, 15BIM08). During mobilization, each piece of equipment is isolated to obtain internal and external offset measurements with respect to the survey platform. All the critical measurements are recorded manually and digitally and entered into their respective programs for calibration. Once calibration is complete and calibration status is considered acceptable, then survey operations commence. The single-beam systems on each survey platform have a dedicated computer, and efforts are made to utilize the same equipment and software versions for each system and platform. However, upgrades and changes occur and require additional setup, measurements, and notation. For the single-beam bathymetry, offsets between the single beam transducers and the Ashtech antenna reference point (ARP) were measured and accounted for in post-processing. Bar checks were performed as a calibration check and helped to correct any drift in the echosounder. Differential Global Positioning System (DGPS) coordinates were obtained using post-processing software packages from the NGS On-Line Positioning User Service, OPUS, and Waypoint Product Group GrafNav, version 8.5.
  2. How accurate are the geographic locations?
    All static base station sessions were processed through OPUS which is maintained by NOAA and NGS. The base location results from OPUS were entered into a spreadsheet to compute a final, time-weighted positional coordinate (latitude, longitude, and ellipsoid height). Base-station positional error for each GPS session was calculated as the absolute value of the final position minus the session position value. The maximum horizontal error of the base station coordinates used for post-processing the single beam bathymetry was 0.00567 seconds latitude and 0.00113 seconds longitude for the USGS benchmark, PAF1, 0.00036 seconds latitude and 0.00030 seconds longitude for PAF2, and 0.00096 seconds latitude and 0.00077 seconds longitude for PAF3.
  3. How accurate are the heights or depths?
    All static base station sessions for PAF1, PAF2, and PAF3 were processed through OPUS which is maintained by the NOAA the NGS. The base location results from OPUS were entered into a spreadsheet to compute a final, time-weighted positional coordinate (latitude, longitude, and ellipsoid height). Base-station positional error for each GPS session was calculated as the absolute value of the final position minus the session position value. SPCMSC standards define the maximum acceptable vertical error for any individual base station GPS session as less than or equal to three times the standard deviation of the ellipsoid height; any occupations exceeding this error are removed and the base station coordinates are recalculated. For the PAF1 base station location, the standard deviation of the ellipsoid height was 0.003 m and the maximum difference from the average ellipsoid for any GPS session was +/- 0.011 m. For the PAF2 base station location, the standard deviation of the ellipsoid height was 0.006 m and the maximum difference from the average ellipsoid for any GPS session was +/- 0.011 m. For the PAF3 base station location, the standard deviation of the ellipsoid height was 0.023 m and the maximum difference from the average ellipsoid for any GPS session was +/- 0.048m. All the processed single-beam bathymetry data (x,y,z) for 2015 are referenced to these base station coordinates. The differentially corrected navigation files (base station GPS processed to boat GPS) were exported from GrafNav version 8.5 and then imported into CARIS HIPS and SIPS version 9.0.17 and merged, by time, with the HYPACK (version 14.0.9.47 for 15BIM05, 15BIM06 and version 13.0.09.17 for 15BIM07, 15BIM08) raw data files at which point the soundings are then geometrically corrected for motion and speed of sound.
  4. Where are the gaps in the data? What is missing?
    This dataset is considered complete for the information presented, as described in the abstract section. Users are advised to read the rest of the metadata record carefully for additional details.
  5. How consistent are the relationships among the observations, including topology?
    These datasets are from one field activity with consistent instrument calibrations.

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?
Access_Constraints: none
Use_Constraints:
The U.S. Geological Survey requests that it be referenced as the originator of this dataset in any future products or research derived from these data. These data should not be used for navigational purposes.
  1. Who distributes the data set? (Distributor 1 of 1)
    Chelsea A. Stalk
    Cherokee Nation Technologies/U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
    Researcher I
    600 4th Street South
    St. Petersburg, FL
    USA

    (727) 502-8000 (voice)
    cstalk@usgs.gov
  2. What's the catalog number I need to order this data set? 15BIM05_SBB_Level_03_1041_ITRF00.txt,15BIM06_SBB_Level_03_1041_ITRF00.txt,15BIM07_SBB_Level_03_1041_ITRF00.txt,15BIM08_SBB_Level_03_1041_ITRF00.txt,15BIM05_SBB_03_1041_NAD83_UTM15N_NAVD88_GEOID12A.txt.15BIM06_SBB_03_1041_NAD83_UTM15N_NAVD88_GEOID12A.txt,15BIM07_SBB_03_1041_NAD83_UTM15N_NAVD88_GEOID12A.txt,15BIM08_SBB_03_1041_NAD83_UTM15N_NAVD88_GEOID12A.txt
  3. What legal disclaimers am I supposed to read?
    This 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.
  4. How can I download or order the data?
  5. What hardware or software do I need in order to use the data set?
    The ASCII text files contained in the .zip archive can be accessed with any standard text file reader.

Who wrote the metadata?

Dates:
Last modified: 19-Mar-2019
Metadata author:
Chelsea A. Stalk
Cherokee Nation Technologies/U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
Researcher I
600 4th Street South
St. Petersburg, FL
USA

(727) 502-8000 (voice)
cstalk@usgs.gov
Metadata standard:
FGDC Content Standards for Digital Geospatial Metadata (FGDC-STD-001-1998)

This page is <https://cmgds.marine.usgs.gov/catalog/spcmsc/2015-320-FA_SBB_xyz_metadata.faq.html>
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