Sections of tracklines where navigation was recorded but no seismic data were logged are not included.
Source_Information:
Source_Citation:
Citation_Information:
Originator: Information unavailable from original metadata - assumed USGS
Publication_Date: unknown
Title: Information unavailable from original metadata
Type_of_Source_Media: disc
Source_Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 20110802
Ending_Date: 20110831
Source_Currentness_Reference:
Survey 2011-013-FA was conducted 20110802 to 20110831. Data were not collected on 20110807, 20110812-20110815, 20110821, and 20110825-20110829 due to weather.
Source_Citation_Abbreviation: USGS
Source_Contribution:
Chirp seismic data were collected using a dual frequency (3.5 and 200 kHz) Knudsen Engineering Limited (KEL) Chirp 3202 system (Knudsen Engineering Limited, 2009) 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 Chirp 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 3.5 - 5.0 kiloHertz, a 0.25 or 0.2 second fire rate (4 or 5 shots per second), a 36-38 microsecond sample interval, and record lengths between 26 and 130 milliseconds. Unique shot point locations are provided in the zip-compressed package for the Knudsen trackline shapefile.
Process_Step:
Process_Description:
A C-shell script was executed that called on Seismic Unix (version 4.1) to read the SEG-Y files, write a Seismic Unix file, and extract SEG-Y trace header information, including shot number, longitude, latitude, year, Julian day, and time of day (UTC) to ASCII text files for each survey line. Files were filtered using AWK (no version) to save records for the first and last shots, and shots at unique longitude/latitude positions in between. The VIM (version 7.2.108) text editor was then used to create a new field in each navigation and trace header text file that combined Julian day and UTC time. Finally, using the newly created field as the 'join' field, the Unix JOIN (no version) command was used to merge coordinates from the navigation text file with corresponding shot records in each trace header file based on this Julian day time field. Geographic coordinates (WGS84) were converted to UTM zone 19 coordinates (WGS84) using Proj (version 4.6.0), and added to the text files in two new columns.
Process_Date: 2011
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: David S. Foster
Contact_Organization: U.S. Geological Survey
Contact_Position: Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Road
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Country: USA
Contact_Voice_Telephone: 508-548-8700 x2271
Contact_Facsimile_Telephone: 508-457-2271
Contact_Electronic_Mail_Address: dfoster@usgs.gov
Process_Step:
Process_Description:
An additional AWK filter was applied to each file created in the previous step to extract trace header records containing the first and last shots, and shots evenly divisible by 500 for each survey line. A 500 shot interval was chosen because it corresponds to the annotation interval provided along the top of the seismic-reflection profile PNG images
Process_Date: 2011
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: David S. Foster
Contact_Organization: U.S. Geological Survey
Contact_Position: Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Road
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Country: USA
Contact_Voice_Telephone: 508-548-8700 x2271
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: dfoster@usgs.gov
Process_Step:
Process_Description:
Text files containing even 500 shot interval records were concatenated into a comma-delimited text file, then imported into ArcMap (version 9.3.1) using 'Add XY data' and saved as points (Geographic, WGS84) in the Esri shapefile format.
Process_Date: 2011
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: David S. Foster
Contact_Organization: U.S. Geological Survey
Contact_Position: Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Road
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Country: USA
Contact_Voice_Telephone: 508-548-8700 x2271
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: dfoster@usgs.gov
Process_Step:
Process_Description:
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.). Removed link to another publication in the Identification section. 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. 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.
Process_Date: 20171005
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Person: VeeAnn A. Cross
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: Mailing and Physical
Address: 384 Woods Hole Road
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: 508-548-8700 x2251
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov
Process_Step:
Process_Description: USGS Thesaurus keywords added to the keyword section.
Process_Date: 20180720
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Person: VeeAnn A. Cross
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: Mailing and Physical
Address: 384 Woods Hole Road
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: 508-548-8700 x2251
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov
Process_Step:
Process_Description:
Added keywords section with USGS persistent identifier as theme keyword.
Process_Date: 20200908
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Person: VeeAnn A. Cross
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: Mailing and Physical
Address: 384 Woods Hole Road
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: 508-548-8700 x2251
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov