U.S. Geological Survey Data Series 429
1U.S. Geological Survey, St. Petersburg, FL 33701.
2Jacobs Technology Inc., St. Petersburg, FL 33701.
U.S. Department of the Interior
U.S. Geological Survey
Florida Integrated Science Center - St. Petersburg
Publications are available from USGS Information Services, Box 25286, Federal Center, Denver, CO 80225-0046 (telephone 1-888-ASK-USGS; e-mail: infoservices@usgs.gov).
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This DVD publication was prepared by an agency of the United States Government. Although these data have been 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.
This disc is readable on any computing platform that has standard DVD driver software installed. The minimum software requirements are a Web browser, Adobe Reader, a text editor, and software capable of reading Microsoft Excel format. If you cannot fully access the information on this page, please contact USGS Information Services at infoservices@usgs.gov or 1-888-ASK-USGS.
In June of 1990 and July of 1991, the U.S. Geological Survey (USGS) conducted geophysical surveys to investigate the shallow geologic framework of the Mississippi-Alabama-Florida shelf in the northern Gulf of Mexico, from Mississippi Sound to the Florida Panhandle. Work was done onboard the Mississippi Mineral Resources Institute R/V Kit Jones as part of a project to study coastal erosion and offshore sand resources. This report is part of a series to digitally archive the legacy analog data collected from the Mississippi-Alabama SHelf (MASH). The MASH data rescue project is a cooperative effort by the USGS and the Minerals Management Service (MMS).
A standardized naming convention was established to allow for better management of scanned trackline images within the MASH data rescue project. Each cruise received a unique field activity identification (ID) based on the year the data were collected, the first two digits of the survey vessel name, and the number of cruises made (to date) by that vessel that year (for example, 91KI2 represents the second cruise made by the R/V Kit Jones in 1991.) The new field activity IDs 90KI1, 90KI2, and 91KI2 presented in this report were originally referred to as Kit Jones 90-1, Kit Jones 90-2, and Kit Jones 91-2 at the USGS in St. Petersburg, FL, and 90013 and 91020 at the USGS in Woods Hole, MA. A table showing the naming convention lineage for cruise IDs in the MASH data rescue series is included as a Portable Data Format (PDF) file. This report serves as an archive of high-resolution scanned Tagged Image File Format (TIFF) and Graphics Interchange Format (GIF) images of the original boomer paper records, navigation files, trackline maps, Geographic Information System (GIS) files, cruise logs, and formal Federal Geographic Data Committee (FGDC) metadata for cruises 90KI1, 90KI2, and 91KI2.
The boomer system uses an acoustic energy source called a plate, which consists of capacitors charged to a high voltage and discharged through a transducer in the water. The source is towed on a sled, at sea level and when discharged emits a short acoustic pulse, or shot, which propagates through the water and sediment column. The acoustic energy is reflected at density boundaries (such as the seafloor or sediment layers beneath the seafloor), detected by the hydrophone receiver, and the amplitude of the reflected energy is recorded by an Edward P. Curley Lab (EPC) thermal plotter. This process is repeated at timed intervals (for example, 0.5 seconds (s)) and recorded for specific intervals of time (for example, 100 milliseconds (ms)). The timed intervals are also referred to as the shot interval or fire rate. On analog records, the recorded interval is referred to as the sweep, which is the amount of time the recorder stylus takes to sweep from the top of the record to the bottom of the record, thereby recording the amplitude of the reflected energy of one shot. In this way, consecutive recorded shots produce a two-dimensional (2-D) vertical image of the shallow geologic structure beneath the ship track.
Many of the geophysical data collected by the USGS prior to the late 1990s was recorded in analog format and stored as paper copies. Scientists onboard made hand-written annotations onto these records to note latitude and longitude, time, line number, course heading, and geographic points of reference. Each paper roll typically contained numerous survey lines and could reach more than 90 feet (ft) in length. All rolls are stored at the USGS Florida Integrated Science Center (FISC)-St. Petersburg, FL. To preserve the integrity of these records and improve accessibility, analog holdings were converted to digital files.
Paper records were scanned at 200 dots per inch (dpi) using an IDEAL/Contex Crystal TX 40-inch (1394) large-format scanner and converted to TIFF format using WIDEimage software (version 2.8.1) in the black and white adaptive mode. Whole roll TIFF images of multiple lines were manually cropped into individual survey lines using WIDEimage. Line images longer than 30,000 pixels were separated into smaller segments for editing with Adobe Photoshop Creative Suite 2 (CS2), where a metadata header file was appended to each survey line or line segment. Images of individual survey lines were named by combining the MASH cruise ID with the survey line (or trackline) number using an underscore, for example, 90KI1_2. If survey lines were longer than 30,000 pixels the split segments were identified by appending a letter in alphabetical order to the line name, for example, 90KI1_5(a). The metadata header file appended to each line or line segment was created in Adobe Illustrator CS2. These header-merged images were then converted to grayscale, flattened, and saved as TIFFs with lossless (LZW) image compression. To facilitate easy viewing or printing of the scanned profiles on any computing platform using Web browser software, TIFF images were scaled to 25% (with constrained proportions and bicubic resampling) in Photoshop and saved as GIF images.
The uncompressed TIFF image files of the whole survey line or line segment (if greater than 30,000 pixels) are stored in the ORIGINALS folder as .zip files. Compressed line images with headers attached are stored in the PRINTABLE folder in both TIFF and GIF formats. Header files, in Adobe Illustrator format, can be found in the HEADERS folder.
Trackline maps and navigation files can be accessed from the Navigation page. The navigation fixes from both the Global Positioning System (GPS) and LOng Range Navigation (LORAN)-C systems are numbered by trackline and correspond to identical hand-numbered vertical event marks on the scanned profiles. A detailed description of the navigation_acquisition_system (1,445-KB PDF) has been included. Scanned images of the available handwritten cruise logbooks are provided as PDF files. Refer to the Acronyms page for expansions of acronyms and abbreviations used in this report. Formal FGDC metadata are also included and can be viewed on the Metadata page. The GIS page contains links to the documents and shapefiles used to create the trackline maps provided in this report.
Site locations for selected CI-87 (Chandeleur Islands, 1987) vibracores are included on the survey and trackline maps. More information on these cores, including scanned PDF versions of the description sheets, text files of the interpreted classification profiles, and formal FGDC metadata can be found in the CI-87_vibracores_folder.
NOTES Annotations made on the original seismic profiles and logbooks refer to two legs of the cruise Kit Jones 90-1 as "Kit Jones 90-1, leg 1" and "Kit Jones 90-1, leg 2". However, the post-cruise report incorporates the leg number into the cruise ID with "Kit Jones 90-1" and "Kit Jones 90-2". This report also uses the post-cruise identifiers, which is consistent with information already available and referenced by the USGS Coastal and Marine Geology (CMG) Infobank (http://walrus.wr.usgs.gov/infobank/).
The map in the Kit Jones 90-1/90-2 post-cruise report shows lines labeled from 1 to 18, while in the original seismic profiles leg 1 lines were annotated 1 to 11 and leg 2 lines 1A to 9A. The authors chose to use the original annotations as the official line names.
Examination of the data, after the cruise, showed that the navigation recorded for line 90KI1_1 ended on 21 June, 1990, at 23:30Z; no navigation exists for the last 12 minutes (min) of line 90KI1_1(d) or any portion of lines 90KI1_1(e) and 90KI1_1(f). The navigation recorded for lines 90KI1_2 and 90KI2_6 was also incomplete and represents only sporadic fixes.
The logbook for Kit Jones 90-1/90-2 was not recovered from the survey personnel for inclusion in this report. The logbook for Kit Jones 91-2 is included only as a transcribed Microsoft Word document provided by R. McBride; the original hand-written logbook was not located.
The initial survey effort for 91KI2 began on 14 May, 1991, but was ended on 22 May, 1991, due to rough seas and poor weather, as noted in the cruise logbook. No usable data were collected during that time period. The second effort, which is presented in this archive, began on 08 July, 1991, and continued successfully through 26 July, 1991.
This disc contains a readme (26-KB .doc file) document, which provides a brief description of the report, GIS files, and all the Hypertext Markup Language (HTML) files, folders, and images used to produce the Web pages included in this report. The Contents page is a diagram of the location of all files and folders contained on this disc and provides links to these files and folders.
To access the information contained on this disc, use a Web browser to open the file index.html. This report is divided into seven sections: Acronyms, Contents, Navigation Data and Maps, Seismic Profiles, Field Activity Logs, Metadata, and GIS. Links at the top and bottom of each page provide access to these sections. This report contains links to the USGS and collaborators or other resources that are accessible only if access to the Internet is available while viewing these documents.
Funding and (or) support for the MASH data rescue project were provided by the USGS and the Minerals Management Service (MMS). Original survey personnel included Jack Kindinger, Mark Byrnes, Randy McBride, Ralph (Monty) Simmons, Jerry Taft, Chuck O'Hara, Ken Parolski, Dana Wiese, Douglas Lockhart, Tom Shelton, and Brian Blanchard. This document was improved by the reviews of Chandra Dreher (Jacobs Technology Inc.) and Shawn Dadisman (USGS) at the FISC-St. Petersburg, FL.
Any additional data or information relevant to the 90KI1, 90KI2, or 91KI2 surveys would be appreciated. Please refer to the Metadata page for contact information.
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