Single-Beam Bathymetric Data Collected in 2013 from the Chandeleur Islands, Louisiana, U.S. Geological Survey (USGS) Field Activity Numbers (FAN) 13BIM03, 13BIM04, 13BIM08.

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Frequently anticipated questions:


What does this data set describe?

Title:
Single-Beam Bathymetric Data Collected in 2013 from the Chandeleur Islands, Louisiana, U.S. Geological Survey (USGS) Field Activity Numbers (FAN) 13BIM03, 13BIM04, 13BIM08.
Abstract:
As part of the Barrier Island Evolution Research Project, scientists from the U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center (SPCMSC) conducted nearshore geophysical surveys around the northern Chandeleur Islands, Louisiana, in July and August of 2013. The objective of the study is to better understand barrier-island geomorphic evolution, particularly storm-related depositional and erosional processes that shape the islands over annual to interannual timescales (1‒5 years). Collecting geophysical data will allow us to identify relationships between the geologic history of the island and its present day morphology and sediment distribution. This mapping effort was the third in a series of three planned surveys in this area. High resolution geophysical data collected in each of three consecutive years along this rapidly changing barrier island system will provide a unique time-series dataset that will significantly further the analyses and geomorphological interpretations of this and other coastal systems, improving our understanding of coastal response and evolution over short time scales (1‒5 years). This data series includes the geophysical data that were collected during two cruises (USGS Field Activity Numbers (FAN) 13BIM02, 13BIM03, and 13BIM04, in July 2013; and FANs 13BIM07 and 13BIM08 in August 2013) aboard the R/V Sallenger, the R/V Jabba Jaw, and the R/V Shark along the northern portion of the Chandeleur Islands, Breton National Wildlife Refuge, Louisiana. Primary data were acquired with the following equipment: (1) a Systems Engineering and Assessment, Ltd., SWATHplus interferometric sonar (468 kilohertz [kHz]), (2) an EdgeTech 424 (424 kHz) chirp sub-bottom profiling system, and (3) two Teledyne Odom Hydrographic Systems, Incorporated, Echotrach CV100 single beam echosounders.
This data series report serves as an archive of processed interferometric swath and single-beam bathymetry data. Geographic information system data products include an interpolated digital elevation model, trackline maps, and point data files. Additional files include error analysis maps, Field Activity Collection System logs, and formal Federal Geographic Data Committee metadata.
Note: These data are scientific in nature and are not to be used for navigation purposes. Any use of trade names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
Supplemental_Information:
The single-beam surveys were acquired and processed to a geodetic reference ellipsoid. The single-beam data was acquired using real-time kinematics (RTK) for 13BIM03 and 13BIM04 in July. The single-beam data for 13BIM08 in August was not acquired using RTK. It was acquired using stand-alone GPS and then post-processed to obtain Differential Global Positioning System DGPS navigation. Both single-beam surveys were referenced to WGS84 (G1150)/ITRF00. The datasets were subsequently transformed horizontally to NAD83 and then vertically to NAVD88 and MLLW, using the GEOID09 model with National Oceanic and Atmospheric Administration (NOAA) VDatum version 3.2 transformation software (http://vdatum.noaa.gov/). The final x,y,z position data from each survey were merged to generate a digital elevation model (DEM) with a cell-size resolution of 50 meters.
  1. How might this data set be cited?
    U.S. Geological Survey, 2017, Single-Beam Bathymetric Data Collected in 2013 from the Chandeleur Islands, Louisiana, U.S. Geological Survey (USGS) Field Activity Numbers (FAN) 13BIM03, 13BIM04, 13BIM08.:.

    Online Links:

    This is part of the following larger work.

    DeWitt, Nancy T., Miselis, Jennifer L., Fredericks, Jake J., Bernier, Julie C., Reynolds, B.J., Kelso, Kyle W., Thompson, Dave M., Flocks, James G., and Wiese, Dana S., 2017, Coastal Bathymetry Data Collected in 2013 from the Chandeleur Islands, Louisiana: U.S. Geological Survey Data Series 1032, U.S. Geological Survey, St. Petersburg, Florida.

    Online Links:

  2. What geographic area does the data set cover?
    West_Bounding_Coordinate: -88.914460
    East_Bounding_Coordinate: -88.761694
    North_Bounding_Coordinate: 30.069698
    South_Bounding_Coordinate: 29.867728
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
    Beginning_Date: 05-Jul-2013
    Ending_Date: 01-Sep-2013
    Currentness_Reference:
    data collection interval
  5. What is the general form of this data set?
    Geospatial_Data_Presentation_Form: ASCII
  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?
    Chan13_SBB_xyz_ITRF00.txt
    ASCII text file containing the processed single-beam bathymetry x,y,z point data in the International Terrestrial Reference Frame of 2000 (ITRF00). (Source: USGS)
    Chan13_SBB_xyz_NAD83_NAVD88_GEOID09_MLLW.txt
    ASCII text file containing the processed single-beam bathymetry x,y,z point data transformed from the International Terrestrial Reference Frame of 2000 (ITRF00) to the North American Datum of 1983 (NAD83) geodetic datum and North American Vertical Datum of 1988 (NAVD88) orthometric height, derived using the GEOID09 model. (Source: USGS)
    ITRF00_X
    ITRF00 X-coordinate (easting) of sample point, in meters (Source: CARIS) Chan13_SBB_xyz_ITRF00.txt = Minimum - Maximum = 315462.816 - 329853.68
    ITRF00_Y
    ITRF00 y-coordinate (northing) of sample point, in meters (Source: CARIS) Chan13_SBB_xyz_ITRF00.txt = Minimum - Maximum = 3305661.293 - 3327822.033
    Ellipsoid
    ITRF00 ellipsoid height of sample point, in meters (Source: CARIS) Chan13_SBB_xyz_ITRF00.txt = Minimum - Maximum = -41.246 - -27.802
    NAD83_X
    NAD83 X-coordinate (easting) of sample point, in meters (Source: VDatum version 3.2) Chan13_SBB_xyz_NAD83_NAVD88_GEOID09_MLLW.txt = Minimum - Maximum = 315463.5782 - 329854.4383
    NAD83_Y
    NAD83 Y-coordinate (northing) of sample point, in meters (Source: VDatum version 3.2) Chan13_SBB_xyz_NAD83_NAVD88_GEOID09_MLLW.txt = Minimum - Maximum = 3305660.709 - 3327821.444
    NAVD88_G09
    The Z-Coordinate in orthometric height (NAVD88) of the sample with respect to GEOID09, in meters (Source: VDatum version 3.2) Chan13_SBB_xyz_NAD83_NAVD88_GEOID09_MLLW.txt = Minimum - Maximum = -13.437 - -0.1469
    NAD83_Lat
    NAD83 Latitude-coordinate of sample point, in decimal degrees (Source: CARIS) Chan13_SBB_xyz_NAD83_NAVD88_GEOID09_MLLW.txt = Minimum - Maximum = 29.869701 - 30.069006
    NAD83_Lon
    NAD83 Longitude-coordinate of sample point, in decimal degrees. (Source: VDatum version 3.2) Chan13_SBB_xyz_NAD83_NAVD88_GEOID09_MLLW.txt = Minimum - Maximum = -88.913649 - -88.762417
    MLLW
    The Z-Coordinate as tidal datum (MLLW) of the sample, in meters. (Source: VDatum version 3.2) Chan13_SBB_xyz_NAD83_NAVD88_GEOID09_MLLW.txt = Minimum - Maximum = -13.395 - -0.0968
    DOY
    Day of the year the data was collected (Source: USGS) Chan13_SBB_xyz_ITRF00.txt = Minimum - Maximum = 193 - 243 Chan13_SBB_xyz_NAD83_NAVD88_GEOID09_MLLW.txt = Minimum - Maximum = 193 - 243
    Year
    Year data was collected (Source: USGS) Chan13_SBB_xyz_ITRF00.txt = 2013 Chan13_SBB_xyz_NAD83_NAVD88_GEOID09_MLLW.txt = 2013
    DataType
    Data type of the sample point. SBB for Single-Beam Bathymetry (Source: USGS) Chan13_SBB_xyz_ITRF00.txt = SBB Chan13_SBB_xyz_NAD83_NAVD88_GEOID09_MLLW.txt = SBB
    GPS_Second
    The GPS second that the data point was acquired. (Source: CARIS) Chan13_SBB_xyz_ITRF00.txt = Minimum - Maximum = 57457.009 - 599960.444 Chan13_SBB_xyz_NAD83_NAVD88_GEOID09_MLLW.txt = Minimum - Maximum = 57457.009 - 599960.444
    HypackLine
    Line number in survey generated by HYPACK. (Source: HYPACK) Chan13_SBB_xyz_ITRF00.txt = Minimum - Maximum = 13BIM03_001_1554 - 13BIM08_142_2159 Chan13_SBB_xyz_NAD83_NAVD88_GEOID09_MLLW.txt = Minimum - Maximum = 13BIM03_001_1554 - 13BIM08_142_2159 Example 13BIM03_001_1554 in which 13BIM03 denotes the USGS FAN number, 001 denotes the line number, and 1554 denotes the time the line started recording.

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
  3. To whom should users address questions about the data?
    Nancy T. DeWitt
    U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
    Geologist
    600 4th Street South
    St. Petersburg, FL
    USA

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

Why was the data set created?

This zip archive contains processed x,y,z data points for the single-beam bathymetry data (SBB) collected in July 2013 (13BIM03 and 13BIM04) and August (13BIM08) around the Chandeleur Islands, Louisiana. The processed single-beam soundings are provided as ASCII x,y,z point data.

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: 2013 (process 1 of 6)
    GPS Base Station Acquisition: A GPS base station was erected at a temporarily installed USGS benchmark (TMRK) located on the sound side of the Chandeleur Islands. A second base station (BRM2) was erected on the furthest northern island providing differential GPS coverage for the survey area within a 15 km radius of either benchmark. GPS receivers recorded the 12-channel full-carrier-phase positioning signals (L1/L2) from satellites via the Thales choke-ring antenna at the base stations. This GPS instrument combination was duplicated on the single-beam survey vessel (rover).
    The SBB data was acquired using RTK for 13BIM03 and 13BIM04 in July. Both base stations were equipped with a Magellan ProFlex500 GPS receiver, a Thales choke ring antenna, a Pacific Crest ADLP-1 390-430 megahertz (MHz) radio, and a Pacific Crest 5 decibel (dB) high power radio whip antenna. The radio whip antennas were placed onto 10-m collapsible masts providing line of site transmission to the vessels (rovers). The GPS and radio components were duplicated on each vessel. The base stations were set to record internally at a rate greater than or equal to the recording rate of the rovers, in this case 5 Hz. The known coordinates of each base station were entered into the GPS receiver and the RTK corrections were broadcast to the roving GPS receivers via the radio links at 5 Hz. The R/V Jabba Jaw recorded GPS positions at 1 Hz using an Ashtech Z-Xtreme GPS receiver and Thales choke ring antenna. The R/V Shark recorded GPS positions at a rate of 5 Hz using a Magellan ProFlex 800 GPS receiver and Ashtech marine antenna (table 2).
    For the August SBB survey (13BIM03) RTK was not used to collect SBB data and all navigation was post-processed to obtain DGPS. The base receivers and the rover receiver recorded their positions concurrently at 1-second (s) intervals throughout the survey. GPS data was acquired and processed in the World Geodetic Datum of 1984 (WGS84) (G1150). Person who carried out this activity:
    Nancy T. DeWitt
    U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
    Geologist
    600 4th Street South
    St. Petersburg, FL
    USA

    (727) 502-8000 (voice)
    ndewitt@usgs.gov
    Date: 2013 (process 2 of 6)
    Single-Beam Bathymetry Acquisition: Depth soundings were acquired aboard the R/V Jabba Jaw and the R/V Shark at 100-milliseconds (ms) using an Odom CV100 echosounder system with a 200 kilohertz (kHz) transducer. Boat motion was recorded on the R/V Jabba Jaw at 50-ms intervals using a Teledyne TSS Dynamic Motion Sensor (TSS DMS-05). The R/V Shark did not record boat motion. To minimize motion errors, the R/V Shark recorded GPS at a high rate (5 Hz) and utilized a short antenna height (lever-arm) in combination with a narrow (4 degree) transducer beam. All sensor data were saved 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 measurements were collected using a Valeport mini Sound Velocity Profiler (SVP) to observe changes in water column speed of sound (SOS). Person who carried out this activity:
    Nancy T. DeWitt
    U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
    Geologist
    600 4th Street South
    St. Petersburg, FL
    USA

    (727) 502-8000 (voice)
    ndewitt@usgs.gov
    Data sources produced in this process:
    • HYPACK raw data files (.RAW), HYPACK target files (.TGT), and SOS files (.txt).
    Date: 2013 (process 3 of 6)
    Differentially Corrected Navigation Processing: The coordinate values for each of the GPS base stations (TMRK and BRM2) are the time-weighted average of values obtained from the National Geodetic Survey's (NGS) On-Line Positioning User Service (OPUS). Depending on the survey design, the coordinates were utilized either during acquisition to provide RTK navigation, or imported into the post-processing software GrafNav (Waypoint Product Group). For post processing, the kinematic GPS data from the survey vessels were processed to the concurrent GPS data from the base stations. Steps were taken to ensure that the trajectories between the base and rover were clean and resulted in fixed positions. GPS data quality could be monitored and manipulated by analyzing the graphs, trajectory maps, and processing logs that GrafNav produces for each GPS session. If poor GPS data was identified, some common tools used to improve the solution included, but were not limited to, omitting a satellite flagged as poor in health, excluding time-segments with cycle slips, or adjusting the satellite elevation mask angle. The final, differentially-corrected, precise DGPS positions were computed at 1-second (s) intervals for each roving GPS session, and then exported in American Standard Code for Information Interchange (ASCII) text format, which replaced the uncorrected real-time rover positions recorded during acquisition. The GPS data were processed and exported in the World Geodetic System of 1984 (WGS84) (G1150) geodetic datum.
    For USGS cruises 13BIM03 and 13BIM04, RTK navigation was implemented. The OPUS derived base station coordinates were programed into their respective base station GPS receivers and position corrections were broadcasted via radio link to the roving GPS receivers located on each survey vessel. However, 13BIM04 was ultimately post-processed using GrafNav version 8.50 after identification of some unreliable navigation segments. RTK was not implemented during cruise 13BIM08 so navigation data was post-processed using GrafNav version 8.4 and all pertinent base information details were accounted during processing. Person who carried out this activity:
    Nancy T. DeWitt
    U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
    Geologist
    600 4th Street South
    St. Petersburg, FL
    USA

    (727) 502-8000 (voice)
    ndewitt@usgs.gov
    Data sources produced in this process:
    • Post-processed differential navigation data for the rover (boat) in ASCII text format. 3 files (forward, reverse, and combined trajectories) are produced for each GPS session file.
    Date: 2013 (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 8.1.5. The raw HYPACK (version 10) 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:
    Nancy T. DeWitt
    U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
    Geologist
    600 4th Street South
    St. Petersburg, FL
    USA

    (727) 502-8000 (voice)
    ndewitt@usgs.gov
    Data sources used in this process:
    • Post-processed differential navigation data files, HYPACK RAW bathymetric data files, HYPACK target (.TGT) files, and SOS (.txt) files all in ASCII text format.
    Data sources produced in this process:
    • 13BIM03_SBB_03_ITRF00_xxx.txt 13BIM04_SBB_03_ITRF00_xxx.txt 13BIM08_SBB_03_ITRF00_xxx.txt
    Date: 2013 (process 5 of 6)
    Single-Beam Bathymetry Error Analysis: The data were edited for outliers in the Single-Beam Editor of CARIS and then 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), which is equivalent to ITRF00, and ellipsoid height in meters. This ASCII file was then imported into ArcMap version 10.1 and reviewed for outliers. An Esri ArcMap Ad-In program script was written locally to evaluate the elevation differences at the intersection of crossing lines. If discrepancies were found at a crossing, the source of the discrepancies was identified and if needed the line or segment of data points in error was statically adjusted or removed. Person who carried out this activity:
    Nancy T. DeWitt
    U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
    Geologist
    600 4th Street South
    St. Petersburg, FL
    USA

    (727) 502-8000 (voice)
    ndewitt@usgs.gov
    Data sources used in this process:
    • 13BIM03_SBB_03_ITRF00_xxx.txt 13BIM04_SBB_03_ITRF00_xxx.txt 13BIM08_SBB_03_ITRF00_xxx.txt
    Data sources produced in this process:
    • Chan13_SBB_xyz_ITRF00.txt
    Date: 2013 (process 6 of 6)
    Datum Transformation: The text files were converted two separate times using VDatum version 3.2 producing two separate files with different vertical datums. The first transformation was from the data acquisition and processing datum (International Terrestrial Reference Frame of 2000, ITRF00) to the North American Datum of 1983 (NAD83) reference frame and the North American Vertical Datum of 1988 (NAVD88) orthometric height using the National Geodetic Survey (NGS) geoid model of 2009 (GEOID09). The second transformation was from ITRF00 to NAD83 for the horizontal reference frame and Mean Lower Low Water (MLLW) tidal datum using GEOID09. Person who carried out this activity:
    Nancy T. DeWitt
    U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
    Geologist
    600 4th Street South
    St. Petersburg, FL
    USA

    (727) 502-8000 (voice)
    ndewitt@usgs.gov
    Data sources used in this process:
    • Chan13_SBB_xyz_ITRF00.txt
    Data sources produced in this process:
    • Chan13_SBB_xyz_NAD83_NAVD88_GEOID09_MLLW.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. The SBB data were collected during concurrent research cruises in July and August, 2013. This dataset is from one research cruise and is therefore internally consistent. Methods were 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. Each system has a dedicated computer, and efforts are made to utilize the same equipment and software versions on both systems. However, upgrades and changes occur and require additional setup, measurements, and notation. DGPS was always implemented for navigational accuracy either during acquisition as RTK or as a post-processing step. These bathymetric data have not been independently verified for accuracy.
    For the SBB, offsets between the single-beam transducers, the Ashtech antenna reference point (ARP), and the TSS motion unit were measured and accounted for on the rovers. For RTK in July (13BIM03 and 13BIm04) all respective base station parameters and rover parameters including antenna height and antenna models were entered into their respective GPS units. For the August surveys, all pertinent measurements were accounted for in the DGPS post processing software packages (National Geodetic Survey On-Line Positioning User Service, OPUS, and Waypoint Product Group GrafNav, version 8.3). Bar checks were also performed as calibration efforts and accounted for any drift in the echosounder.
  2. How accurate are the geographic locations?
    All static GPS base station sessions were run through the On-Line Positioning User Service (OPUS) maintained by the National Oceanic and Atmospheric Administration (NOAA) and the National Geodetic Survey (NGS). The base location results from OPUS were entered into a spreadsheet to compute one final coordinate and error analysis for that base location. Using the OPUS values for each day, and the total time that data were collected each day, the average daily weighted value of occupation time was calculated; longer occupation times held more value than shorter times. The final value for latitude, longitude, and ellipsoid was the weighted average of all the GPS session processed with OPUS. This value was entered in GrafNav version 8.1 as the base station coordinates. Error was calculated using output from OPUS for each day and was calculated as the absolute value of the final value minus the daily value. The maximum horizontal error of the base station coordinates used for post-processing the single-beam bathymetry was 0.00042 decimal seconds latitude and 0.00096 decimal seconds longitude for TMRK and 0.00015 decimal seconds latitude and 0.00030 decimal seconds longitude for BRM2.
  3. How accurate are the heights or depths?
    All static base station sessions for TMRK and BRM2 were processed through On-Line Positioning User Service (OPUS) maintained by the National Oceanic and Atmospheric Administration (NOAA) and the National Geodetic Survey (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 3 times the standard deviation of the ellipsoid height; any occupations exceeding this error are removed and the base station coordinates are recalculated. For TMRK base location the standard deviation of the ellipsoid height was 0.014 m and the maximum difference from the average ellipsoid for any GPS session was +/- 0.030 m. For BRM2 base location the standard deviation of the ellipsoid height was 0.013 m and the maximum difference from the average ellipsoid for any GPS session was +/- 0.031 m.
    All the RTK and the post-processed SBB data (x,y,z) for 2013 are referenced to these base station coordinates. The differentially corrected navigation files (base station GPS processed to boat GPS) were exported from GrafNav version 8.4 and then imported into CARIS HIPS and SIPS version 7.1 and merged by time with the HYPACK (version 10.0.5.31) raw data files at which point the soundings are then geometrically corrected for motion and speed of sound. For the single-beam soundings, elevation differences at 320 crossings were within +/- 0.15 m which accounts for 68 percent of the crossings.
  4. Where are the gaps in the data? What is missing?
    These are complete post-processed xyz bathymetric data points from acoustic single-beam data collected in July and August 2013 from the northern Chandeleur Islands.
  5. How consistent are the relationships among the observations, including topology?
    This file represents the post-processed bathymetric data (x,y,z) collected during SBB surveys. They represent data coverage for the single-beam portion of the 2013 Chandeleur survey, specifically FAN 13BIM03, 13BIM04, and 13BIM08. Refer to the online data series linkage for field logs, vessel platform descriptions, and other survey information; this information is directly available at https://doi.org/10.3133/ds1032

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?
Access_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.
Use_Constraints: These data should not be used for navigational purposes.
  1. Who distributes the data set? (Distributor 1 of 1)
    Nancy T. DeWitt
    U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
    Geologist
    600 4th Street South
    St. Petersburg, FL
    USA

    (727) 502-8000 (voice)
    ndewitt@usgs.gov
  2. What's the catalog number I need to order this data set? Downloadable Data File Name
  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: 2017
Metadata author:
Nancy T. DeWitt
U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
Geologist
600 4th Street South
St. Petersburg, FL
USA

(727) 502-8000 (voice)
ndewitt@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/Chan13_SBB_xyz_metadata.faq.html>
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