PNG formatted images of Knudsen 3202 chirp seismic-reflection profiles collected by the USGS within Buzzards Bay and sand shoals of Vineyard Sound, MA, 2011

Frequently anticipated questions:

• What does this data set describe?
  1. How might this data set be cited?
  2. What geographic area does the data set cover?
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
  5. What is the general form of this data set?
  6. How does the data set represent geographic features?
  7. How does the data set describe geographic features?
• Who produced the data set?
  1. Who are the originators of the data set?
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
• Why was the data set created?
• How was the data set created?
  1. From what previous works were the data drawn?
  2. How were the data generated, processed, and modified?
  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?
  2. How accurate are the geographic locations?
  3. How accurate are the heights or depths?
  4. Where are the gaps in the data? What is missing?
  5. How consistent are the relationships among the data, including topology?
• How can someone get a copy of the data set?
  1. Are there legal restrictions on access or use of the data?
  2. Who distributes the data?
  3. What's the catalog number I need to order this data set?
  4. What legal disclaimers am I supposed to read?
  5. How can I download or order the data?
• Who wrote the metadata?

What does this data set describe?

1. How might this data set be cited?
   U.S. Geological Survey, 2014, PNG formatted images of Knudsen 3202 chirp seismic-reflection profiles collected by the USGS within Buzzards Bay and sand shoals of Vineyard Sound, MA, 2011: Open-File Report 2013-1020, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Coastal and Marine Science Center, Woods Hole, Massachusetts.

   Online Links:

   • https://doi.org/10.3133/ofr20131020
   • https://pubs.usgs.gov/of/2013/1020/GIS_catalog/seisimage/knudsen/2011-013_seisimage.zip

   This is part of the following larger work.
   Pendleton, Elizabeth A., Andrews, Brian D., Danforth, William W., and Foster, David S., 2014, High-resolution geophysical data collected aboard the U.S. Geological Survey research vessel Rafael to supplement existing datasets from Buzzards Bay and Vineyard Sound, Massachusetts: Open-File Report 2013-1020, U.S. Geological Survey, Reston, VA.

   Online Links:

   • https://doi.org/10.3133/ofr20131020
   • https://pubs.usgs.gov/of/2013/1020/

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -70.829567
   East_Bounding_Coordinate: -70.443945
   North_Bounding_Coordinate: 41.554338
   South_Bounding_Coordinate: 41.432077
   

3. What does it look like?

   https://pubs.usgs.gov/of/2013/1020/GIS_catalog/seisimage/knudsen/knudsen_013.png (PNG)

   Woods Hole Coastal and Marine Science Center Swath Knudsen seismic reflection profiles surrounding the Elizabeth Islands and Martha's Vineyard, MA

4. Does the data set describe conditions during a particular time period?

   Beginning_Date: 02-Aug-2011

   Ending_Date: 31-Aug-2011

   Currentness_Reference:

   Data were not collected on 20110807, 20110812-20110815, 20110821, and 20110825-20110829 due to weather.

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 raster data types:
      • Dimensions, type Pixel
   2. What coordinate system is used to represent geographic features?
      
7. How does the data set describe geographic features?

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?
3. To whom should users address questions about the data?
   Elizabeth A. Pendleton

   U.S. Geological Survey

   Geologist

   384 Woods Hole Road

   Woods Hole, MA
   

   USA

   508-548-8700 x2259 (voice)

   508-457-2310 (FAX)

   ependleton@usgs.gov

Why was the data set created?

How was the data set created?

1. From what previous works were the data drawn?

   data acq. (source 1 of 1)

   U.S. Geological Survey, unknown, Information unavailable from original metadata.

   Type_of_Source_Media: disc
   Source_Contribution:

   Seismic data were collected using a dual frequency (3.5 and 200 kHz) Knudsen Engineering Limited (KEL) Chirp 3202 system with transducers mounted on a rigid pole on the starboard side of the R/V Rafael of Woods Hole, MA. Knudsen SounderSuite seismic acquisition software was used to control the 3202 system, digitally log trace data in the Society of Exploration Geophysicists Y (SEG-Y) Revision 1 format (Norris and Faichney), and record DGPS navigation coordinates to the SEG-Y trace headers in arc seconds. The transducer draft was 0.5 m below the water surface, and the draft offset was accounted for during data acquisition. Navigation coordinates and water depths from the 200-kHz channel were logged together in ASCII formatted files for each survey line. Data were acquired at a peak frequency of 5.0 kHz, a .25 second fire rate, a 36 -38 microsecond sample interval, and record lengths between 26 and 130 milliseconds. A total of 940 km of seismic data were collected. A total of 940 km of seismic data were collected.

2. How were the data generated, processed, and modified?

   Date: 2013 (process 1 of 5)

   An executable C-shell script called on SIOSEIS (version 2007.8) to 1) mute water column portions of Knudsen 3202 seismic traces using the water depths recorded in the 200kHz channel; 2)apply gain and automatic gain control functions to the traces; and 3) write the resulting traces to new "mute_gain" SEG-Y files, which were used for creation of PNG browse images and digital interpretation. Person who carried out this activity:
   

   David S. Foster

   U.S. Geological Survey

   Geologist

   384 Woods Hole Rd

   Woods Hole, MA
   

   USA

   508-548-8700 x2271 (voice)

   508-457-2310 (FAX)

   dfoster@usgs.gov

   Date: 2013 (process 2 of 5)

   An executable C-Shell script called on Seismic Unix (version 4.1) to read the SEG-Y files and plot the data as 8-bit gray scale Postscript files. All images were created with a horizontal scale of 100 traces per inch. The profiles contain 50 milliseconds of Two-Way Travel Time within an 12-inch vertical window, yielding 4.2 milliseconds per inch. Postscript images were converted to PNG format using ImageMagick (version 5.5.6). Person who carried out this activity:
   

   Elizabeth Pendleton

   U.S. Geological Survey

   Geologist

   384 Woods Hole Rd

   Woods Hole, MA
   

   USA

   508-548-8700 x2259 (voice)

   508-457-2310 (FAX)

   ependleton@usgs.gov

   Date: 05-Oct-2017 (process 3 of 5)

   Edits to the metadata were made to fix any errors that MP v 2.9.36 flagged. This is necessary to enable the metadata to be successfully harvested for various data catalogs. In some cases, this meant adding text "Information unavailable" or "Information unavailable from original metadata" for those required fields that were left blank. Other minor edits were probably performed (title, publisher, publication place, etc.). Added the DOI link in the Identification section - both as the first link and as part of the Larger Work citation. Fixed the publication date and also the Larger Work citation title to match what is available online. Updated the link to the project page in the abstract as well as the field activity links. Fixed the browse graphic link. The source information was incomplete and had to be modified to meet the standard. Fixed a link in the distribution section. The metadata date (but not the metadata creator) was edited to reflect the date of these changes. The metadata available from a harvester may supersede metadata bundled within a download file. Compare the metadata dates to determine which metadata file is most recent. 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)

   vatnipp@usgs.gov

   Date: 20-Jul-2018 (process 4 of 5)

   USGS Thesaurus keywords added to the keyword section. 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)

   vatnipp@usgs.gov

   Date: 08-Sep-2020 (process 5 of 5)

   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)

   vatnipp@usgs.gov

3. What similar or related data should the user be aware of?
   Andrews, B.D., Ackerman, S.D., Baldwin, W.E., Foster, D.S., and Schwab, W.C., 2013, High-Resolution Geophysical Data From the Inner Continental Shelf at Vineyard Sound, Massachusetts: Open-File Report 2012-1006, U.S. Geological Survey, Reston, VA.

   Online Links:

   • https://pubs.usgs.gov/of/2012/1006/

   Ackerman, S.D., Andrews, B.D., Foster, D.S., Baldwin, W.E., and Schwab, W.C., 2013, High-Resolution Geophysical Data from the Inner Continental Shelf: Buzzards Bay, Massachusetts: Open-File Report 2012-1002, U.S. Geological Survey, Reston, VA.

   Online Links:

   • https://pubs.usgs.gov/of/2012/1002/

   Pendleton, E.A., Twichell, D.C., Foster, D.S., Worley, C.R., Irwin, B.J., and Danforth, W.W., 2012, High-Resolution Geophysical Data From the Sea Floor Surrounding the Western Elizabeth Islands, Massachusetts: Open-File Report 2011-1184, U.S. Geological Survey, Reston, VA.

   Online Links:

   • https://pubs.usgs.gov/of/2011/1184/

   Turecek, A.M., Danforth, W.W., Baldwin, W.E., and Barnhardt, W.A., 2012, High-Resolution Geophysical Data Collected Within Red Brook Harbor, Buzzards Bay, Massachusetts, in 2009: Open-File Report 2010-1091, U.S. Geological Survey, Reston, VA.

   Online Links:

   • https://pubs.usgs.gov/of/2010/1091/

   Stockwell, John, 2008, CWP/SU: Seismic Uni*x: Center for Wave Phenomena - Colorado School of Mines, Golden, CO.

   Online Links:

   • http://www.cwp.mines.edu/cwpcodes/index.html

   Other_Citation_Details: version 43R3
   

   Henkart, Paul, 2007, SIOSEIS: Scripps Institution of Oceanography, University of California - San Diego, LaJolla, CA.

   Online Links:

   • http://sioseis.ucsd.edu/index.html

   Norris, Michael W., and Faichney, Alan K., 2002, SEGY Rev.1 Data Exchange Format1: Society of Exploration Geophysicists, Tulsa, OK.

   Online Links:

   • http://www.seg.org/documents/10161/77915/seg_y_rev1.pdf

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?
   Differential Global Positioning System (DGPS) navigation data were acquired with a Communications Systems International (CSI), Inc. LGBX Pro receiver. Navigation data were sent to the Knudsen SounderSuite acquisition application, which logged the coordinates to individual trace headers in the Society of Exploration Geophysicists Y (SEG-Y) Revision 1 format (Norris and Faichney, 2002). A 2 m horizontal offset between the seismic transducers and the DGPS receiver was not accounted for during data acquisition, and resulting positional accuracy is assumed to be better than 10 m.
3. How accurate are the heights or depths?
   
4. Where are the gaps in the data? What is missing?
   One PNG image exists for each seismic profile identified in the 'image' attribute field of the shapefile '2011-013-FA_Knudsen_tracklines.shp' located in the directory 'https://pubs.usgs.gov/of/2013/1020/GIS_catalog/tracklines/'
5. How consistent are the relationships among the observations, including topology?
   Processed seismic data were converted to PNG format for ease of seismic trace display. Quality control was conducted during processing. Changes in water depth, bottom type, and acquisition parameters during the survey caused significant variability in seismic trace amplitudes and subsurface penetration. Profiles in shallow water areas experienced the most detrimental effects. Data quality generally improved as the survey progressed into deeper water.

How can someone get a copy of the data set?

1. Who distributes the data set? (Distributor 1 of 1)
   
   Elizabeth A. Pendleton

   U.S. Geological Survey

   Geologist

   384 Woods Hole Rd.

   Woods Hole, MA
   

   (508) 548-8700x2259 (voice)

   (508) 457-2310 (FAX)

   ependleton@usgs.gov
2. What's the catalog number I need to order this data set? Downloadable Data
3. What legal disclaimers am I supposed to read?
   Neither the U.S. Government, the Department of the Interior, nor the USGS, nor any of their employees, contractors, or subcontractors, make any warranty, express or implied, nor assume any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, nor represent that its use would not infringe on privately owned rights. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of these data or related materials. Any use of trade, product, or firm 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?
   • Availability in digital form:

     Data format:	This WinZip (v 14.5) file contains PNG images of chirp seismic-reflection profiles surrounding the Elizabeth Islands and Martha's Vineyard, MA, and the associated metadata. in format PNG (version ImageMagick v 5.5.6) Size: 769
     Network links:	https://pubs.usgs.gov/of/2013/1020/GIS_catalog/seisimage/knudsen/2011-013_seisimage.zip https://pubs.usgs.gov/of/2013/1020/html/ofr2013-1020_GIS_catalog.html

   • Cost to order the data: None

5. Is there some other way to get the data?
   Digital copies of these chirp seismic data may also be obtained in the SEG-Y Rev. 1 standard format upon request. The data would be packaged on DVD, and contain the Knudsen-processed, envelope traces.
6. What hardware or software do I need in order to use the data set?
   These data can be viewed with any PNG image viewing software.

Who wrote the metadata?

Dates:

Last modified: 18-Mar-2024

Metadata author:

Elizabeth Pendleton

U.S. Geological Survey

Geologist

384 Woods Hole Rd.

Woods Hole, MA

(508) 548-8700x2259 (voice)

(508) 457-2310 (FAX)

whsc_data_contact@usgs.gov

Contact_Instructions:

The metadata contact email address is a generic address in the event the person is no longer with USGS. (updated on 20240318)

Metadata standard:

FGDC Content Standards for Digital Geospatial Metadata (FGDC-STD-001-1998)