Swath derived bathymetric grids of Lostmans and Lower Shark Rivers, Florida (2015) in Esri ASCII grid format

Metadata also available as - [Outline] - [Parseable text] - [XML]

Frequently anticipated questions:

What does this data set describe?

Swath derived bathymetric grids of Lostmans and Lower Shark Rivers, Florida (2015) in Esri ASCII grid format
High resolution bathymetry mapping of the coastal rivers and inland lakes along the Southwest coast of Everglades National Park (ENP) is greatly needed from the perspective of resource mapping and future research and hydrologic modeling efforts. To this end, bathymetric surveys of 8 coastal rivers were completed in 2004 as part of a cooperative project between the US Geological Survey (USGS) and the South Florida Water Management District (SFWMD). Recent analyses of geo_databases from the project in 2004 shows that Lostmans River and several segments of Shark River remained to be mapped. Completed surveys for these areas will provide and invaluable and complete set of bathymetric surveys of coastal rivers along the Southwest coast of ENP.
This report serves as an archive of processed interferometric swath bathymetry data that were collected during one cruise (USGS Field Activity Numbers 2015_304_FA) in Lower Shark River, Florida. Geographic information system data products include: a 5 m_cell_size interpolated bathymetry grid surface and point data files. Also included in this archive are Geographic Information System (GIS) data products: gridded map data (in Esri binary and ASCII grid format), and a color_coded bathymetry map (in PDF format). Additional files include Field Activity Collection System logs, and formal Federal Geographic Data Committee (FGDC) metadata.
The swath bathymetry data were collected and processed in the WGS84 geodetic reference ellipsoid. Vertical positions were transformed to NAVD88 using National Oceanic and Atmospheric Administration (NOAA), National Geodetic Survey GEOID12a software. The final corrected X,Y,Z position data were used to generate a digital elevation model with a cell_size resolution of 5 meters.
  1. How might this data set be cited?
    Hansen, Mark, 2015, Swath derived bathymetric grids of Lostmans and Lower Shark Rivers, Florida (2015) in Esri ASCII grid format: Archive of Bathymetry Data Collected in South Florida from 1995 to 2015 U.S. Geological Survey Data Series-1031, U.S. Geological Survey, St. Petersburg, Florida.

    Online Links:

  2. What geographic area does the data set cover?
    West_Bounding_Coordinate: -81.217
    East_Bounding_Coordinate: -81.105
    North_Bounding_Coordinate: 25.596
    South_Bounding_Coordinate: 25.330
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
    Beginning_Date: 17-Mar-2015
    Ending_Date: 19-Mar-2015
    Data assumed to be constant over time but may change due to geologic processes.
  5. What is the general form of this data set?
    Geospatial_Data_Presentation_Form: raster digital data
  6. How does the data set represent geographic features?
    1. How are geographic features stored in the data set?
      This is a Raster data set. It contains the following vector data types (SDTS terminology):
      • Point (3113238)
    2. What coordinate system is used to represent geographic features?
      Grid_Coordinate_System_Name: Universal Transverse Mercator
      UTM_Zone_Number: 17
      Scale_Factor_at_Central_Meridian: 0.9996
      Longitude_of_Central_Meridian: -83.0
      Latitude_of_Projection_Origin: 0.0
      False_Easting: 500000.0
      False_Northing: 0.0
      Planar coordinates are encoded using coordinate pair
      Abscissae (x-coordinates) are specified to the nearest 0.01
      Ordinates (y-coordinates) are specified to the nearest 0.01
      Planar coordinates are specified in meters
      The horizontal datum used is D North American 1983.
      The ellipsoid used is GRS 1980.
      The semi-major axis of the ellipsoid used is 6378137.0.
      The flattening of the ellipsoid used is 1/298.257222101.
      Depth_Datum_Name: NAVD88
      Depth_Resolution: 0.01
      Depth_Distance_Units: meters
      Depth_Encoding_Method: Explicit depth coordinate included with horizontal coordinates
  7. How does the data set describe geographic features?
    DS1031-SWRivers2015_LostmansR_NAD83_NAVD88_G12a.grid.asc, DS1031-SWRivers2015_LSharkR_NAD83_NAVD88_G12a_grid.asc
    Gridded data surface derived from swath bathymetry, vessel (R/V Mako) acquired bathymetric data in Esri ASCII grid format. (Source: Esri)
    Grid node
    Node value (Source: Esri)
    Range of values

Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
    • Mark Hansen
  2. Who also contributed to the data set?
    U.S. Geological Survey, Coastal and Marine Geology Program, St. Petersburg Coastal and Marine Science Center. Mark Hansen was the USGS principal investigator. Nancy DeWitt performed a significant portion of bathymetric survey data collection and processing. Gordan Anderson provided logistical support.
  3. To whom should users address questions about the data?
    Mark Hansen
    U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center
    600 4th Street South
    St. Petersburg, FL

    (727) 502-8000 (voice)

Why was the data set created?

Complete surveys of Lostmans River and Lower Shark River that were partially mapped by the USGS in 2004.

How was the data set created?

  1. From what previous works were the data drawn?
    USGS Southwest Rivers bathymetry (source 1 of 1)
    U.S. Geological Survey, Unpublished material, 2015 Southwest Rivers, Florida swath bathymetry.

    Type_of_Source_Media: digital tabular data
    Source_Contribution: Original processed swath bathymetric data.
  2. How were the data generated, processed, and modified?
    Date: 2015 (process 1 of 4)
    Swath Bathymetry Acquisition: The interferometric swath bathymetry data were collected aboard the R/V Mako using a SEA SWATHplus-H 468 kHz interferometric sonar system mounted on a pole that was attached to the bow of the boat. Boat position and motion data were recorded in real-time using a CodaOctopus F190R wetpod inertial measurement unit (IMU) mounted underwater between the transducer heads to minimize lever arm geometry errors between the observed depths and associated vessel motion. Real-time corrected positions were acquired via the use of the OmniSTAR HP (High-Precision differential global navigation satellite system) satellite constellation subscription. OmniSTAR HP position correction data and motion data from the IMU were integrated with interferometric soundings in the SWATHplus software package versions 3.7.17 with positional and calibration offsets pre-defined by a session file(.sxs), allowing for real-time_corrected depths. Prior to deployment, all equipment offsets were surveyed in dry dock with the use of a laser total station. During the survey all swath tracklines were recorded in SEA SWATHplus raw data format (.sxr). A Valeport Mini Sound Velocity Sensor (SVS) was attached to the transducer mount and collected continuous SOS measurements at the depth of the transducers. These values were directly read and incorporated into the SWATHplus acquisition software giving real-time speed of sound at the transducer while underway. In addition, a separate sound velocity profiler (Valeport miniSVP) was used to collect speed of sound profiles (water surface to seafloor) at intervals throughout the survey. Person who carried out this activity:
    Mark Hansen
    U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
    600 4th Street South
    St. Petersburg, FL

    (727) 502-8000 (voice)
    Data sources produced in this process:
    • Raw sensor data and GPS Carrier_phase data in binary format.
    Date: 2015 (process 2 of 4)
    Swath Bathymetry Processing: Position data recorded by the Coda-Octopus F190R IMU system were corrected in real time via the OmniSTAR HP differential navigation system. The IMU also applied real-time motion corrections for heave, roll, and pitch to the vertical component of each position fix. The corrected positions were then integrated with the observed bathymetric values to calculate a final ellipsoid height and position representing the elevation of the seafloor with respect to the geodetic reference frame ITRF05 across the swath range. SWATHplus serves as both an acquisition software and initial processing software. Preliminary roll calibration trackline data were collected and processed using Systems Engineering and Assessment Ltd SWATHplus and Grid Processor software version 3.7.17. Instrument offset and calibrations values were input into the session file (.sxs) and the raw data files (.sxr) were then processed using the updated system configuration containing roll calibration values, measured equipment offsets, acquisition parameters, navigation and motion from the F190R, SOS at the sonar head, and SVP cast data. Any calibration offsets or acoustic filtering applied in SWATHplus is also written to the processed data file (.sxp). The initial real time processing datum for the swath and backscatter data was ITRF05, which is the acquisition datum for OmniSTAR HP position and navigation data. All processed data files were imported into CARIS HIPS and SIPS version 7.1, and the original sounding data were edited for outliers using the program's depth filters and reference surfaces. Any remaining outliers were then edited out manually. A CARIS BASE (Bathymetry with Associated Statistical Error) surface with associated CUBE (Combined Uncertainty and Bathymetry Estimator) sample surface was created from the edited soundings dataset. A BASE hypothesis is the estimated value of a grid node representing all the soundings within a chosen resolution or grid_cell size (for example, 5 m) weighted by uncertainty and proximity giving the final value as a sample of the data within the specific grid cell. This algorithm allows for multiple grid_node hypotheses to be verified or overridden by the user, while maximizing processing efficiency. A 5_m resolution CUBE surface was created to perform initial hypothesis editing using the CARIS Subset Editor tool, followed by higher resolution surface detail editing within subset editor. The sample X,Y,Z data were exported as ASCII text at a 5 x 5 m sample resolution in the ellipsoid datum of ITRF05. Person who carried out this activity:
    Mark Hansen
    U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
    600 4th Street South
    St. Petersburg, FL

    (727) 502_8000 (voice)
    Data sources produced in this process:
    • Swath processed data in SWATHplus binary format.
    Date: 2015 (process 3 of 4)
    The sounding data was entered into ArcMap version 10.1 (a gridding and contouring software package) ARCMap (Esri) and saved as an ASCII text file in Esri GRID format. Person who carried out this activity:
    U.S. Geological Survey
    Attn: Mark Hansen
    600 4th Street South
    St. Petersburg, FL

    (727) 502-8000 (voice)
    (727) 502-8032 (FAX)
    Data sources produced in this process:
    • DS1031-SWRivers2015_LostmansR_NAD83_NAVD88_G12a.grid.asc, DS1031-SWRivers2015_LSharkR_NAD83_NAVD88_G12a_grid.asc
    Date: 13-Oct-2020 (process 4 of 4)
    Added keywords section with USGS persistent identifier as theme keyword. Person who carried out this activity:
    U.S. Geological Survey
    Attn: VeeAnn A. Cross
    Marine Geologist
    384 Woods Hole Road
    Woods Hole, MA

    508-548-8700 x2251 (voice)
    508-457-2310 (FAX)
  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 the platform. 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 entered into their respective programs. For the interferometric swath bathymetry, offsets between the sonar head and the DGPS antennas were measured and entered into the CodaOctopus F190R internal setup program. DGPS was provided through the OmniSTAR High Performance wide_area GPS service. DGPS is always implemented for navigational accuracy either during acquisition or as a post_processing step. These bathymetric data have not been independently verified for accuracy.
  2. How accurate are the geographic locations?
    The stated horizontal accuracy of the OmniSTAR HP navigation subscription used during swath bathymetry acquisition is reported by the service as 0.15 m (95+/- of the time).
  3. How accurate are the heights or depths?
    The stated vertical accuracy of the OmniSTAR HP navigation subscription used during swath bathymetry acquisition is 0.18 m (95+/- of the time). The Coda Octopus F190R IMU, which integrates the OmniSTAR HP position with motion, measures vessel velocity (0.014 m/s), roll and pitch (+/- 0.025 degrees), heading (1 m baseline 0.1 degrees), and heave (5 cm per meter of depth). The vertical accuracy for the SWATHplus-H system varies with depth and across track range.
  4. Where are the gaps in the data? What is missing?
    These are complete post_processed xyz bathymetric data points from acoustic swath data collected in March 2015 in Lostmans and Lower Shark River, Florida.
  5. How consistent are the relationships among the observations, including topology?
    This file represents the post_processed bathymetric data (X,Y,Z) collected during a swath bathymetry survey. They represent data coverage for the swath portion of the 2015 Lostmans and Lower Shark River survey, specifically Field Activity Number (FAN) 2015-304-FA.

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?
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.
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)
    Mark E. Hansen
    U.S. Geological Survey
    600 Fourth St. South
    St. Petersburg, FL

    (727) 502_8000 (voice)
    (727) 502_8032 (FAX)
  2. What's the catalog number I need to order this data set? Swath bathymetry, vessel (R/V Mako) acquired, bathymetric data.
  3. What legal disclaimers am I supposed to read?
    The data have no explicit or implied guarantees. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although these data have been processed successfully on a computer system at the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. The USGS or the U.S. Government shall not be held liable for improper or incorrect use of the data described and/or contained herein.
  4. How can I download or order the data?

Who wrote the metadata?

Last modified: 09-Nov-2021
Metadata author:
United States Geological Survey, St. Petersburg Coastal and Marine Science Center
Attn: SPCMSC Data Management Group
600 4th Street South
St. Petersburg, Florida

727-502-8000 (voice)
Metadata standard:
FGDC Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)

This page is <https://cmgds.marine.usgs.gov/catalog/spcmsc/DS1031-SWRivers2015_WGS84-G12a_metadata.grid.faq.html>
Generated by mp version 2.9.50 on Tue Nov 9 16:47:42 2021