Attribute_Accuracy_Report:
The accuracy of the data was determined during data collection. This dataset is derived from a single field survey using identical equipment set-ups, and staff; therefore, the dataset is internally consistent. Methods were 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 antenna reference point (ARP) were measured using a geodimeter and accounted for during acquisition and (or) in post-processing. Differential Global Positioning System (DGPS) coordinates were obtained using the following post-processing software packages: NovAtel's Waypoint Product Group GrafNav, version 8.60.5025).
These data were collected during a single field activity with consistent instrument calibrations.
This data release contains single-beam bathymetry data points in the horizontal position and vertical elevation (x,y,z) from February 2017 collected off Madeira Beach, Florida. Users are advised to read the complete metadata record carefully for additional details.
Process_Step:
Process_Description:
Global Navigation Satellite System (GNSS) Acquisition: GNSS data was recorded at a primary base station and aboard each roving vessel. The primary base station was FDOT FPRN base station FLIS located approximately 15 kilometers (km) north of the survey area. The base station was operational for the entire survey and the Receiver Independent Exchange Format (RINEX) datafiles (FLIS045M00.17O, FLIS045M00.17N, and FLIS045M00.17G) were downloaded from the FPRN website post survey. FLIS was the name at the time of the single-beam survey in 2017. But at the time of this publication, the location has been renamed FLIB in the FDOT system. The roving vessels were each outfitted with a Spectra Geospatial SP90M GNSS receivers and GNSS antennae recording data at 10 hertz (10 epochs/second). The GNSS files were converted from proprietary G-file format into the non-proprietary RINEX raw data file format using RINEX Converter version 3.00. The base and rover RINEX files were post processed together in a subsequent step to obtain differentially corrected navigation data, which is described later in the metadata. Example RINEX filename TVEE0450.17O where the convention TVEE is the four-letter rover name, 045 is the day of year, 0 is the session number, 17 is the year and O is the observation file (or N for navigation file, M for meteorlogical file, G for Global Navigation Satellite Navigation System (GLONASS) navigation message file.
Process_Date: 2017
Source_Produced_Citation_Abbreviation: *.17O, *.17N, *.17M
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Nancy T. DeWitt
Contact_Organization: U.S. Geological Survey
Contact_Position: Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 600 4th Street South
City: St. Petersburg
State_or_Province: FL
Postal_Code: 33701-4846
Country: USA
Contact_Voice_Telephone: 727-502-8000
Contact_Electronic_Mail_Address: ndewitt@usgs.gov
Process_Step:
Process_Description:
Single-Beam Bathymetry Acquisition: TVEE collected 87.12 line-km (62 lines), SHRK collected 145.46 line-km (60 lines) and the CHUM collected 61.83 line-km (80 lines). Boat motion was recorded at 50-millisecond (ms) using a SBG Ellipse A motion sensor. HYPACK A Xylem Brand (version 16.1.9.0), 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 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. Data from the GNSS receiver, motion sensor, and echosounder 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 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 17 successful sound velocity casts were collected and ranged in depth from 0.15 to 6.48 m (average 2.14 m), and in sound velocity from 1518.18 to 1525.69 meters per second (m/s) (average 1520.94 m/s).
Process_Date: 2017
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Nancy T. DeWitt
Contact_Organization: U.S. Geological Survey
Contact_Position: Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 600 4th Street South
City: St. Petersburg
State_or_Province: FL
Postal_Code: 33701-4846
Country: USA
Contact_Voice_Telephone: 727-502-8000
Contact_Electronic_Mail_Address: ndewitt@usgs.gov
Process_Step:
Process_Description:
Differentially Corrected Navigation Processing: The FDOT FPRN datasheet for FLIS were retrieved from the database and the base station coordinates were converted from NAD83 (2011) EPOCH 2010.0 into WGS84 (G1762) equivalent to ITRF2008 using the HTDP online transformation utility version 3.2.5 (
https://www.ngs.noaa.gov/TOOLS/Htdp/Htdp.shtml). The WGS84 (G1762) epoch realization was introduced in 2013. The survey acquisition dates succeed this date; therefore, it was the appropriate datum realization for post-processing the navigation data which was acquired in the WGS84 (G1762) datum. The resultant base position used for post-processing was 27°5247.88931 North (WGS84-G1762), 82°5033.69685 West (WGS84-G1762), and -17.543 m ellipsoid height (WGS84-G1762).
The kinematic trajectories (rover to base) were processed using NovAtel's Waypoint GrafNav software version 8.60.5025. The rover RINEX files and the base RINEX files were imported into Grafnav, converted into proprietary files, and the kinematic (rover) GNSS data session from the survey vessel was post-processed to the concurrent base GNSS data session. Analyzing the data plots, trajectory maps, processing logs, satellite health plots, and other viewing utilities that GrafNav produces, provided measures to attain trajectory solutions (between the rover and the base) free of erroneous data that resulted in fixed positions. Some analytic examples include 1) excluding satellites flagged by the program as having bad/poor health or cycle slips, 2) Excluding poor satellite time segments that have a negative influence toward a fixed solution, and 3) adjusting the satellite elevation mask angle to improve the position solutions. This process was repeated for every GNSS data session(Hansen and others, 2017). The final differentially corrected, precise DGPS positions were computed at and exported in American Standard Code for Information Interchange (ASCII) text format in WGS84 (G1762) UTM 17N geodetic datum. Filename example 17TST02_045_2017_FLIS_TVEE_A.txt where the convention 17TST02 is the subFAN, 045 is day of year, 2017 is the year, FLIS is the base station used, TVEE is the rover, and A is the GPS session from A to Z.
Contact_Information:
Contact_Person_Primary:
Contact_Person: Nancy T. DeWitt
Contact_Organization: U.S. Geological Survey
Contact_Position: Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 600 4th Street South
City: St. Petersburg
State_or_Province: FL
Postal_Code: 33701-4846
Country: USA
Contact_Voice_Telephone: 727-502-8000
Contact_Electronic_Mail_Address: ndewitt@usgs.gov
Process_Step:
Process_Description:
Bathymetry Processing: All data were processed using CARIS HIPS and SIPS (Hydrographic Information Processing System and Sonar Information Processing System) version 10.2. First, a vessel file *.vhf, unique to the platform, was created that contains the surveyed offsets measurements between the sensors. A CARIS project was created using the *.vhf file, and then the HYPACK *.RAW and the SVP profiles *.SVP were loaded. Next, the differentially corrected navigation files were imported using the generic data parser tool. Then, the differently corrected navigation files overwrote every non-differential position in the HYPACK *.RAW file based upon time. The bathymetric data components (position, motion, depth, and SOS) were then georeferenced and geometrically corrected in CARIS to produce processed x,y,z positional data. Once georeferenced, the data were reviewed and edited for outliers, including further review in the Subset Editor utility for crossing status, and questionable areas or data points were removed. The geometrically corrected point data were then exported as an x,y,z ASCII text file referenced to WGS84 (G1762) UTM 17N (Hansen and others, 2017).
Source_Used_Citation_Abbreviation: *.VHF
Source_Used_Citation_Abbreviation: *.RAW
Source_Used_Citation_Abbreviation: *.SVP
Source_Used_Citation_Abbreviation: 17TST02_045_2017_FLIS_TVEE_A.txt
Process_Date: 2017
Source_Produced_Citation_Abbreviation: 17TST02_SBB_ITRF08_Level_003_xxx.txt
Source_Produced_Citation_Abbreviation: 17TST03_SBB_ITRF08_Level_003_xxx.txt
Source_Produced_Citation_Abbreviation: 17TST04_SBB_ITRF08_Level_003_xxx.txt
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Nancy T. DeWitt
Contact_Organization: U.S. Geological Survey
Contact_Position: Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 600 4th Street South
City: St. Petersburg
State_or_Province: FL
Postal_Code: 33701-4846
Country: USA
Contact_Voice_Telephone: 727-502-8000
Contact_Electronic_Mail_Address: ndewitt@usgs.gov
Process_Step:
Process_Description:
Quality Control, Quality Assurance (QA/QC) and Uncertainty Analysis: The single-beam data exported from CARIS HIPS and SIPS (x,y,z ASCII text files) were transformed in Esri ArcMap version 10.4.1 to a point shapefile (.shp) utilizing the "Create Feature Class From XY Table" geoprocessing tool. The projection was set to WGS84 UTM 17N. The generated shapefile was visually scanned for any obvious outliers or problems. Next, a polyline shapefile (representing tracklines) was produced from the point shapefile using XTools Pro (version 16.1) "Make Polylines from Points" geoprocessing tool for each survey platform (subFANs 17TST02, 17TST03 and 17TST04). Utilizing both the x,y,z (point) and trackline (polyline) shapefiles, a Python script 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 5 m (Hansen and others, 2017). The maximum crossing error for TVEE (17TST02), when crossing a trackline it previously surveyed, was 18 cm. The maximum crossing error for SHRK (17TST03), when crossing a trackline it previously surveyed, was 22 cm. The maximum crossing error for CHUM (17TST04), when crossing a trackline it previously surveyed, was 43 cm. Any crossings greater than 30 cm were reviewed a final time for errors and either removed or adjusted, based on the situation when compared with the other vessels. The shapefiles were merged into one large file and sent through the python crossing program a last time. The final crossing file had 1847 crossings ranging from 0.00 to 34 cm in which 80.7% were 10 cm or less; 13.5% were between 10-15 cm; 6.1% were between 15-30 cm, and 0.22% were greater than 30cm. These files were then exported from Esri ArcMap as x,y,z ASCII text (.txt) files using the XTools Pro "Table to Text" function. The resultant ASCII text file can be downloaded from this data release in Madeira_Beach_2017_SBES_xyz.zip, and the trackline shapefile Madeira_Beach_2017_SBES_tracklines.zip.
Source_Used_Citation_Abbreviation: 17TST02_SBB_ITRF08_Level_003_xxx.txt
Source_Used_Citation_Abbreviation: 17TST03_SBB_ITRF08_Level_003_xxx.txt
Source_Used_Citation_Abbreviation: 17TST04_SBB_ITRF08_Level_003_xxx.txt
Process_Date: 2017
Source_Produced_Citation_Abbreviation: Madeira_Beach_2017_SBES_WGS84_UTM17N_xyz.txt
Source_Produced_Citation_Abbreviation: Madeira_Beach_2017_SBES_tracklines.shp
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Nancy T. DeWitt
Contact_Organization: U.S. Geological Survey
Contact_Position: Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 600 4th Street South
City: St. Petersburg
State_or_Province: FL
Postal_Code: 33701-4846
Country: USA
Contact_Voice_Telephone: 727-502-8000
Contact_Electronic_Mail_Address: ndewitt@usgs.gov
Process_Step:
Process_Description:
Datum Transformation: NOAA/NGS's VDatum v.3.6 was used to transform the single-beam data points' horizontal and vertical datums (x,y,z). The transformation was from WGS84 (G1762) into NAD83 (horizontal) UTM 17N and NAVD88 (vertical) using GEOID12B. VDatum reports a nationwide standard deviation of 2.0 centimeters (cm) for ellipsoid - NAD83 transformations, and a nationwide standard deviation of 5.0 cm for NAD83 to NAVD88 transformations in the coastal regions of the continental U.S. 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. The resultant data points ASCII data file can be downloaded from this data release in Madeira_Beach_2017_SBES_xyz.zip.
Contact_Information:
Contact_Person_Primary:
Contact_Person: Nancy T. DeWitt
Contact_Organization: U.S. Geological Survey
Contact_Position: Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 600 4th Street South
City: St. Petersburg
State_or_Province: FL
Postal_Code: 33701-4846
Country: USA
Contact_Voice_Telephone: 727-502-8000
Contact_Electronic_Mail_Address: ndewitt@usgs.gov
Process_Step:
Process_Description:
DEM Creation: Using Esri ArcGIS version 10.4.1, a polygon shapefile of the single-beam data extent was created (MadeiraBeach_2017_SBB_polygon.shp). Next using ArcGIS "polygon to raster" conversion tool a raster mask of the shapefile was created (mb2017ply20m). Next using the single-beam x,y,z data a 20 x 20-m cell resolution DEM was generated using the natural neighbor algorithm. The algorithm computation results produce minimum and maximum values (-26.469 to -37.569) different then the ascii text xyz values (-23.133 to -38.648) from which it was created. The DEM was then clipped to the raster mask using ArcGIS Spatial Analyst "extract by raster mask" tool and then exported as a GeoTIFF file for this data release.
Source_Used_Citation_Abbreviation: Madeira_Beach_2017_SBES_WGS84_UTM17N_xyz.txt
Process_Date: 2023
Source_Produced_Citation_Abbreviation: MadeiraBeach_2017_SBES_20m_DEM.tif
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Nancy T. DeWitt
Contact_Organization: U.S. Geological Survey
Contact_Position: Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 600 4th Street South
City: St. Petersburg
State_or_Province: FL
Postal_Code: 33701-4846
Country: USA
Contact_Voice_Telephone: 727-502-8000
Contact_Electronic_Mail_Address: ndewitt@usgs.gov
