Geospatial Navigational Data Associated with Chirp Sub-Bottom Profiles Collected During USGS Field Activity Number 2024-310-FA in 2024 from Wallops and Assawoman Islands, Virginia

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 Number 2024-310-FA in 2024 from Wallops and Assawoman Islands, Virginia
Abstract:
In June 2024, the U.S. Geological Survey (USGS) conducted a nearshore geologic assessment, including bathymetric mapping, near Wallops and Assawoman Islands, Virginia (VA). This work was performed to collect bathymetry to initialize hydrodynamic models and acquire new sub-bottom profile data to connect with existing USGS offshore lines collected along the Delmarva Peninsula, Maryland and VA, in 2015 (Sweeney and others, 2015). These newly acquired datasets will be used to help evaluate impacts of shoreface engineering activities on system ecogeomorphology. Geophysical data were collected as part of the USGS Interconnected Coastal Environments at Decadal Timescales and Coastal Sediment Availability and Flux (CSAF) projects; more information about the CSAF project can be found at https://usgs.gov/csaf. 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 Number (FAN) 2024-310-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., 20250318, Geospatial Navigational Data Associated with Chirp Sub-Bottom Profiles Collected During USGS Field Activity Number 2024-310-FA in 2024 from Wallops and Assawoman Islands, Virginia:.

    This is part of the following larger work.

    Forde, Arnell S., Stalk, Chelsea A., Ciarletta, Daniel J., and Miselis, Jennifer L., 20250318, Chirp Sub-Bottom Profile Geophysical Data Collected in 2024 From Wallops Island and Assawoman Island, Virginia: U.S. Geological Survey data release doi:10.5066/P1NZ6CC2, 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: -75.531739
    East_Bounding_Coordinate: -75.400892
    North_Bounding_Coordinate: 37.864244
    South_Bounding_Coordinate: 37.755383
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
    Beginning_Date: 01-Jun-2024
    Ending_Date: 12-Jun-2024
    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 0.0197577306. Longitudes are given to the nearest 0.0248912658. 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 (2024-310-FA_gis.zip): The shapefiles created as part of this dataset are a derivative of the ASCII CSV navigation files provided in 2024-310-FA_nav.zip, 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 file, 2024-310-FA_trkln.shp (149 data records), is a polyline geospatial dataset representing all the chirp sub-bottom profile tracklines; 2024-310-FA_1000sht.shp (1270 data records) is a point geospatial dataset representing the 1,000th shot interval; and 2024-310-FA_sol.shp (149 data records) provides locations for the start of each seismic line as a point geospatial dataset.
    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 National Aeronautics and Space Administration. The authors thank Captain Andrew Farmer of the USGS St. Petersburg Coastal and Marine Science Center (SPCMSC) for his assistance in data collection and piloting the Research Vessel (R/V) Sallenger. Field activity planning was performed by Daniel Ciarletta and Jennifer Miselis; data collection conducted by Chelsea Stalk, Jennifer Miselis, and Daniel Ciarletta; and data processing performed by Arnell Forde. This document was improved by scientific/editorial and metadata reviews from Noreen Buster and Tess Rivenbark-Terrano 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 FAN 2024-310-FA. Additional survey and data details are available from the USGS Coastal and Marine Geoscience Data System (CMGDS) at https://cmgds.marine.usgs.gov/services/activity.php?fan=2024-310-FA.

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: 22-Jul-2024 (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 geographic information system (GIS) software. The final output files are as follows: (1) 2024-310-FA_nav.csv contains unique shotpoint positions (along each line) for the entire survey, (2) 2024-310-FA_1000sht.csv includes 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) 2024-310-FA_sol.csv has the start-of-line locations for each trackline. These CSV files are available from the data release, see 2024-310-FA_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:
    • 2024-310-FA_nav.csv
    • 2024-310-FA_1000sht.csv
    • 2024-310-FA_sol.csv
    Date: 22-Jul-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 file, 2024-310-FA_1000sht.csv, provided in the data release was imported into ArcGIS Pro software to produce a geographic representation of the 1,000-shotpoint data collected within the survey area. The 1,000-shot-interval point shapefile (2024-310-FA_1000sht.shp) was generated to correlate shot locations with evenly spaced 1,000-shot index markers along the top of the printable profile images. Likewise, a point shapefile containing the start of line locations for all chirp tracklines, that are based on the reformatted text file, 2024-310-FA_sol.csv, was used to create 2024-310-FA_sol.shp. Finally, the 2024-310-FA_nav.csv file containing unique shotpoint positions was imported into 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 a shapefile (2024-310-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 (2024-310-FA.kmz). All geospatial files can be found in 2024-310-FA_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:
    • 2024-310-FA_1000sht.csv
    • 2024-310-FA_sol.csv
    • 2024-310-FA_nav.csv
    Data sources produced in this process:
    • 2024-310-FA_1000sht.shp
    • 2024-310-FA_sol.shp
    • 2024-310-FA_trkln.shp
    • 2024-310-FA.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:

    Sweeney, E.M., Pendleton, E.A., Ackerman, S.D., Andrews, B.D., Baldwin, W.E., Danforth, W.W., Foster, D.S., Thieler, E.R., and Brothers, L.L., 2015, High-resolution geophysical data collected along the Delmarva Peninsula 2015, U.S. Geological Survey Field Activity 2015-001-FA (ver. 3.0, May 2016): U.S. Geological Survey data release doi:10.5066/F7P55KK3, U.S. Geological Survey - Woods Hole Coastal and Marine Science Center, Woods Hole, Massachusetts.

    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 an Applanix POS MV Wavemaster II inertial aided navigation system (IANS), which is accurate to within 0.5-2 meters (m). Positions from the POS MV IANS were recorded and written to the seismic trace headers approximately every 0.20 seconds, with unique navigation fixes being recorded every second. The approximate 4-m offset between the chirp and vessel's IANS reference point 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 149 seismic lines were collected during this field activity. 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, 2024-310-FA_logs.zip.
  5. How consistent are the relationships among the observations, including topology?
    These datasets are from one field activity with consistent instrument calibrations. Seismic data were acquired during a single survey, 2024-310-FA, which occurred between June 1 and 12, 2024.

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?
Access_Constraints No access constraints. Please see 'Distribution Information' for details.
Use_Constraints These data are marked with a Creative Common CC0 1.0 Universal License. These data are in the public domain and do not have any use constraints. Users are advised to read the dataset's metadata thoroughly to understand appropriate use and data limitations.
  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? 2024-310-FA_1000sht.shp, 2024-310-FA_sol.shp, 2024-310-FA_trkln.shp, 2024-310-FA.kmz
  3. What legal disclaimers am I supposed to read?
    Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
  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: 18-Mar-2025
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/2024-310-FA_geospatial_metadata.faq.html>
Generated by mp version 2.9.51 on Mon Mar 31 10:29:54 2025