Geospatial Navigational Data Associated with Chirp Sub-Bottom Profiles Collected During USGS Field Activity Numbers 2021-326-FA and 2022-326-FA in 2021 and 2022 from Duck, North Carolina

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

Frequently anticipated questions:

What does this data set describe?

Title:
Geospatial Navigational Data Associated with Chirp Sub-Bottom Profiles Collected During USGS Field Activity Numbers 2021-326-FA and 2022-326-FA in 2021 and 2022 from Duck, North Carolina
Abstract:
In June/December 2021 and July 2022, the U.S. Geological Survey (USGS) and U.S. Army Corps of Engineers, Engineer Research and Development Center (USACE-ERDC) conducted repeat, nearshore geologic assessments, including bathymetric mapping, near Duck, North Carolina (NC). This work was performed in support of efforts to map the shoreface, characterize stratigraphy, and investigate changes in seafloor elevations near the USACE Field Research Facility and to measure the co-evolution of the morphology and geology of the shoreface before/after a storm and during recovery. Geophysical data were collected as part of the USGS Coastal Sediment Availability and Flux and DUring Nearshore Event eXperiment (DUNEX) projects. The data release associated with this metadata record serves as an archive of high-resolution chirp sub-bottom trace data and navigation files. Shapefiles (.shp) provided in the data release represent point and polyline vector datasets of Field Activity Numbers (FANs) 2021-326-FA and 2022-326-FA chirp sub-bottom profile tracklines, start of lines, and 1,000-shot-interval locations.
  1. How might this data set be cited?
    Forde, Arnell S., 20240708, Geospatial Navigational Data Associated with Chirp Sub-Bottom Profiles Collected During USGS Field Activity Numbers 2021-326-FA and 2022-326-FA in 2021 and 2022 from Duck, North Carolina:.

    This is part of the following larger work.

    Forde, Arnell S., Miselis, Jennifer L., Conery, Ian, DeWitt, Nancy T., and Buster, Noreen A., 20240708, Chirp Sub-Bottom Profile Geophysical Data Collected in 2021 and 2022 From Duck, North Carolina: U.S. Geological Survey data release doi:10.5066/P1346BEP, U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center, St. Petersburg, Florida.

    Online Links:

  2. What geographic area does the data set cover?
    West_Bounding_Coordinate: -75.753303
    East_Bounding_Coordinate: -75.728878
    North_Bounding_Coordinate: 36.195403
    South_Bounding_Coordinate: 36.182639
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
    Beginning_Date: 17-Jun-2021
    Ending_Date: 13-Jul-2022
    Currentness_Reference:
    ground condition
  5. What is the general form of this data set?
    Geospatial_Data_Presentation_Form: Vector digital data (point and polyline)
  6. How does the data set represent geographic features?
    1. How are geographic features stored in the data set?
      This is a Vector data set.
    2. What coordinate system is used to represent geographic features?
      Horizontal positions are specified in geographic coordinates, that is, latitude and longitude. Latitudes are given to the nearest 0.0197454907. Longitudes are given to the nearest 0.0259102598. Latitude and longitude values are specified in Decimal Degrees. The horizontal datum used is WGS_1984.
      The ellipsoid used is WGS_84.
      The semi-major axis of the ellipsoid used is 6378137.0.
      The flattening of the ellipsoid used is 1/298.257223563.
  7. How does the data set describe geographic features?
    Entity_and_Attribute_Overview:
    Geospatial files (DUNEX_gis.zip): The shapefiles created as part of this dataset are a derivative of the ASCII CSV navigation files provided in DUNEX_nav.zip (organized into individual sub-folders per FAN), which is available from the data release. The navigation and geospatial files mainly share the same attribute labels and definitions, aside from "FID" and "Shape", which are specific to the .shp files. Due to ArcGIS Pro character restrictions, the point shapefile attribute labels were changed to “DOY_HR_MIN” within the attribute tables. The detailed attribute descriptions for these files are provided in the data dictionary (DataDictionary_SBP.docx), the metadata are not complete without this file. The trackline files, 2021-326-FA_trkln.shp (44 data records) and 2022-326-FA_trkln.shp (16 data records), are polyline geospatial datasets representing all the chirp sub-bottom profile tracklines; 2021-326-FA_1000shot.shp (151 data records) and 2022-326-FA_1000shot.shp (65 data records) are point geospatial datasets representing the 1,000th shot interval; and 2021-326-FA_sol.shp (44 data records) and 2022-326-FA_sol (16 data records) provide locations for the start of each seismic line as point geospatial datasets.
    Entity_and_Attribute_Detail_Citation:
    The entity and attribute information were generated by the individual or agency identified as the originator of the dataset. Please review the rest of the metadata record for additional details and information.

Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
    • Arnell S. Forde
  2. Who also contributed to the data set?
    Funding and (or) support for this study was provided by the USGS Coastal and Marine Hazards and Resources Program and the USACE-ERDC, who provided the Lighter Amphibious Resupply Cargo (LARC) amphibious vehicle/survey vessel, personnel to pilot the vessel, geophysical and bathymetry equipment to conduct this survey, and personnel to operate the survey equipment. Field activity planning was performed by Jennifer Miselis and Noreen Buster (USGS) in collaboration with Ian Conery (USACE-ERDC); data collection conducted by Andrew Farmer, Nancy DeWitt, John (Rob) Mitchell (USACE-ERDC), and Jason Pipes (USACE-ERDC); and data processing performed by Arnell Forde. This document was improved by scientific/editorial and metadata reviews from Wayne Baldwin (WHCMSC) and Breanna Williams of the SPCMSC.
  3. To whom should users address questions about the data?
    Arnell S. Forde
    U.S. Geological Survey
    Geologist
    600 4th Street South
    Saint Petersburg, FL
    USA

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

Why was the data set created?

The purpose of the data release described herein is to archive and disseminate digital chirp sub-bottom profile data and associated files collected during USGS FANs 2021-326-FA and 2022-326-FA. Additional survey and data details are available from the USGS Coastal and Marine Geoscience Data System (CMGDS) at, https://cmgds.marine.usgs.gov/fan_info.php?fan=2021-326-FA and https://cmgds.marine.usgs.gov/fan_info.php?fan=2022-326-FA. More information about the DUNEX project can be found at, https://www.usgs.gov/centers/whcmsc/science/usgs-dunex-operations-outer-banks.

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: 13-Jul-2022 (process 1 of 2)
    Navigation information was extracted from the seismic trace headers (seismic data available from the data release) using Seismic Unix release 44 software (Cohen and Stockwell, 2010), processed with PROJ.5.1.0 software (https://proj.org/) to generate Universal Transverse Mercator (UTM) Zone 18 North (N) coordinates from latitude and longitude coordinates (World Geodetic System of 1984, WGS84), and then saved as ASCII text files in comma-separated values (CSV) format. Navigation files for each sub-bottom line, saved by line number, were concatenated into comma-delimited text files so they could be represented geospatially using in geographic information system (GIS) software. The final output files are as follows: (1) 2021-326-FA_nav.csv and 2022-326-FA_nav.csv contain unique shotpoint positions (along each line) for the entire survey, (2) 2021-326-FA_1000sht.csv and 2022-326-FA_1000sht.csv include the 1,000-shot-interval locations that were generated to correlate shot locations along the trackline with evenly spaced 1,000-shot index markers along the top of the printable profile images, and (3) 2021-326-FA_sol.csv and 2022-326-FA_sol.csv have the start-of-line locations for each trackline. These CSV files are available from the data release, see DUNEX_nav.zip. Person who carried out this activity:
    Arnell S. Forde
    U.S. Geological Survey
    Geologist
    600 4th Street South
    St. Petersburg, FL
    USA

    727-502-8000 (voice)
    aforde@usgs.gov
    Data sources used in this process:
    • *.txt
    Data sources produced in this process:
    • 2021-326-FA_nav.csv
    • 2021-326-FA_1000sht.csv
    • 2021-326-FA_sol.csv
    • 2022-326-FA_nav.csv
    • 2022-326-FA_1000sht.csv
    • 2022-326-FA_sol.csv
    Date: 25-Mar-2024 (process 2 of 2)
    The reformatted text files referenced in the previous process step were then further processed using Esri ArcGIS Pro 3.2.1 software to generate shapefiles. The 1,000-shot navigation files, 2021-326-FA_1000sht.csv and 2022-326-FA_1000sht.csv, provided in the data release were imported into ArcGIS Pro software to produce a geographic representation of the 1,000-shotpoint data collected within the survey area. 1,000-shot-interval point shapefiles (2021-326-FA_1000shot.shp and 2022-326-FA_1000shot.shp) were generated to correlate shot locations with evenly spaced 1,000-shot index markers along the top of the printable profile images. Likewise, point shapefiles containing the start of line locations for all chirp tracklines, that are based on the reformatted text files 2021-326-FA_sol.csv and 2022-326-FA_sol.csv, were used to create 2021-326-FA_sol.shp and 2022-326-FA_sol.shp. Finally, the 2021-326-FA_nav.csv and 2022-326-FA_nav.csv files containing unique shotpoint positions were imported to ArcGIS Pro to produce a geographic representation of the sub-bottom profile tracklines collected within the survey area. The 'PointsToLine (Data Management)' geoprocessing tool was used to create two shapefiles (2021-326-FA_trkln.shp and 2022-326-FA_trkln.shp) in which individual chirp shotpoints were connected to form tracklines. A non-proprietary version of the shapefiles was created with the 'Map To KML (Conversion)' geoprocessing tool that converted the map document layers to keyhole markup language (.kml) format prior to them being compressed (zipped) and saved as a .kmz file (DUNEX_2021_2022.kmz). All geospatial files can be found in DUNEX_gis.zip. Person who carried out this activity:
    Arnell S. Forde
    U.S. Geological Survey
    Geologist
    600 4th Street South
    St. Petersburg, FL

    (727) 502-8000 (voice)
    aforde@usgs.gov
    Data sources used in this process:
    • 2021-326-FA_1000sht.csv
    • 2021-326-FA_sol.csv
    • 2021-326-FA_nav.csv
    • 2022-326-FA_1000sht.csv
    • 2022-326-FA_sol.csv
    • 2022-326-FA_nav.csv
    Data sources produced in this process:
    • 2021-326-FA_1000shot.shp
    • 2021-326-FA_sol.shp
    • 2021-326-FA_trkln.shp
    • 2022-326-FA_1000shot.shp
    • 2022-326-FA_sol.shp
    • 2022-326-FA_trkln.shp
    • DUNEX_2021_2022.kmz
  3. What similar or related data should the user be aware of?
    Cohen, J.K., and Stockwell, J.W., Jr., 2010, Seismic Un*x Release No. 44: An open source software package for seismic research and processing: Center for Wave Phenomena, Colorado School of Mines, Golden, Colorado.

    Online Links:

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

  1. How well have the observations been checked?
  2. How accurate are the geographic locations?
    As the sub-bottom profile data were acquired, the position of the vessel was continuously determined by a Real-Time Kinematic Global Positioning System (RTK-GPS) utilizing a base/rover setup, which is accurate to within 2 centimeters. Positions from the RTK-GPS were recorded and written to the seismic trace headers approximately every 0.20 seconds, with unique navigation fixes being recorded every second. The approximately 1-meter offset between the chirp and vessel's RTK-GPS antenna has not been accounted for in the comma-delimited American Standard Code for Information Interchange (ASCII) navigation or geospatial files.
  3. How accurate are the heights or depths?
  4. Where are the gaps in the data? What is missing?
    A total of 60 seismic lines were collected during these field activities. Additional survey and data details are available from the Field Activity Collection System (FACS) logs and acquisition geometry figure, which are included as supplemental information in the download file, DUNEX_logs.zip.
  5. How consistent are the relationships among the observations, including topology?
    These datasets are from three field activities with consistent instrument calibrations. Seismic data were collected during two FANs, which occurred between June 17-18 and December 3-10 of 2021 (2021-326-FA) and July 12-13, 2022 (2022-326-FA).

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?
Access_Constraints None. These data are held in the public domain.
Use_Constraints 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 the data in future products or derivative research.
  1. Who distributes the data set? (Distributor 1 of 1)
    SPCMSC Data Management Group
    U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center
    600 4th Street South
    St. Petersburg, FL
    USA

    (727) 502-8000 (voice)
    gs-g-spcmsc_data_inquiries@usgs.gov
  2. What's the catalog number I need to order this data set? 2021-326-FA_1000shot.shp, 2021-326-FA_sol.shp, 2021-326-FA_trkln.shp, 2022-326-FA_1000shot.shp, 2022-326-FA_sol.shp, 2022-326-FA_trkln.shp, DUNEX_2021_2022.kmz
  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 geospatial files were created for use with Esri ArcGIS Pro 3.2.1 software. They may also be viewed with QGIS (https://www.qgis.org/en/site/, 2024), Google Earth (https://earth.google.com/, 2024), or other GIS software capable of importing the data.

Who wrote the metadata?

Dates:
Last modified: 17-Jun-2024
Metadata author:
SPCMSC Data Management Group
U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center
600 4th Street South
St. Petersburg, FL
USA

(727) 502-8000 (voice)
gs-g-spcmsc_data_inquiries@usgs.gov
Metadata standard:
Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)
This page is <https://cmgds.marine.usgs.gov/catalog/spcmsc/DUNEX_geospatial_metadata.faq.html>
Generated by mp version 2.9.51 on Mon Jul 8 11:19:20 2024