FILE: readme.txt U.S. GEOLOGICAL SURVEY Open-File Report 00-352 SEAMARC 1A SIDESCAN SONAR MOSAIC, CORES AND DEPOSITIONAL INTERPRETATION OF THE MISSISSIPPI FAN: ArcView GIS Data Release By Valerie Paskevich US Geological Survey Woods Hole, MA 02543 David C. Twichell US Geological Survey Woods Hole, MA 02543 William Schwab US Geological Survey Woods Hole, MA 02543 INTRODUCTION This CD-ROM (Compact Disc-Read Only Memory) has been produced in accordance with the ISO 9660 CD-ROM Standard and is therefore capable of being read on any computing platform that has appropriate CD-ROM driver software installed. Access to the data and information contained on this CD-ROM was developed using the HyperText Markup Language (HTML) utilized by the World Wide Web (WWW) project. Development of the CD-ROM documentation and user interface in HTML allows a user to access the information using WWW information browsers (e.g., Microsoft Internet Explorer, Netscape). To access the information contained on this disk, the user may open the file 'index.htm' at the top level directory of this CD-ROM with their favorite WWW browser. This starting page will determine the web browser being used and open the web page designed specifically for that browser. The indexnn.htm file is for Netscape Navigator and the indexms.htm is intended for Microsoft Internet Explorer browser. All HTML documentation is written utilizing some HTML 3.0 enhancements. The disk should be viewable by all WWW browsers but may not properly format on some older browsers. In addition, JAVA scripts and applets are being on some pages. Due to inconsistencies in the various web browsers, these scripts may not function properly in all circumstances. Also, there are some links to USGS collaborators and USGS websites on this CD-ROM. These links are only accessible if access to the Internet is available during browsing of the CD-ROM, and if those linked sites are operating. ********************************************** BACKGROUND This CD-ROM releases data that were used in several publications dealing with processes associated with recent deposition on the Mississippi Fan. Because of the interest in the findings of this work amongst geologists it seemed appropriate to make the data and not just the summary interpretive reports available to the scientific community. There are three main directories on this CD-ROM. These directories include: 1. Directory htmldocs This directory contains the HTML files and supporting graphics to allow the user access to the CD-ROM via any World Wide Web browser. 2. Directory data This directory contains 8 additional sub-directories with the various data layers. Metadata documentation describing each of the data layers are contained in the individual directories. The major data layers are organized in separate directories and are described as: bathyc/ - This directory contains bathymetric contours for the Gulf of Mexico stored in ESRI ArcView shapefile format. coast/ - This directory contains 2 land body data layers in ArcView shapefile format: 1) the US coastal states, and 2) Mexico and Cuba land body. These shapefiles have been clipped to fit the Gulf of Mexico project area. cores/ - This directory contains information associated with the cores collected during the R/V FARNELLA 90-4 cruise. Core information is available in a variety of formats including an ArcView shapefile, Microsoft Excel spreadsheet, HTML formatted table and an ASCII text file. Additional subdirectories include images of core field descriptions and xrays. gloria/ - This directory contains the 250 m resolution GLORIA sidescan sonar mosaic for the Gulf of Mexico. The image is used as in the MSFAN overview portion of the ArcView project. The image is available in either a GEOTIFF or JPEG format. Associated with each of the image files are world files (*.tfw or *.jgw). It is also available with either a black or white background surrounding the digital mosaic. imagery/ - This directory contains 2 additional sub-directories: 1) raw/ and 2) enhanced/ The enhanced directory contains the 25 m images, seamarc and GLORIA, used in the ArcView MSFAN 25m view. Because the images have been enhanced for better viewing within ArcView, a second set of unenhanced images has been made available in the directory raw. The images are available in either a GEOTIF or JPEG format. Associated with each of the image files are world files(*.tfw or *.jgw). interp/ - This directory contains the various ArcView shapefiles that depict the senior author's interpretation. misc/ - This directory contains misc data layers used in the ArcView project. nav/ - This directory contains the navigation collected during the R/V FARNELLA 90-3 cruise. The data are available as an ArcView shape file in two formats and an ASCII text file. 3. Directory java This directory contains the JAVA script used to accomplish the image dissolve on the start page (indexnn.htm) for the Netscape browser. This script didn't work properly with the Microsoft Internet Explorer browser, so the Internet Explorer start page (indexms.htm) uses a different, embeded JAVA script. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Software Requirements This CD-ROM (Compact Disc-Read Only Memory) has been produced in accordance with the ISO 9660 CD-ROM Standard and is therefore capable of being read on any computing platform that has appropriate CD-ROM driver software installed. No specific software is required to access this CD-ROM, nor is any software provided as part of the CD-ROM. The HTML documentation is written utilizing some HTML 3.0 enhancements. The disk should be viewable by all WWW browsers but may not properly format on some older WWW browsers. To view the entire contents of the disk, the user's browser should be JAVA enabled, but it is not required to simply browse the disk's contents. For those people who wish to access the disk and do not have a World Wide Web browser available, they may do so by accessing the disk via their computer's operating system. The data coverages and imagery archived on this disk are intended to be used in Geographic Information Systems (GIS). Most notably for the data coverages (bathymetry contours, samples and geologic interpretive overlays) the GIS of choice has been ESRI's ARC/INFO and ArcView, and the data have been stored in various formats supported by these software packages. As for the raster imagery of the study area, the images are stored in geotiff format. These images may be read by any program capable of reading the TIFF format. Although some programs do not interpret the additional geotiff tags, the image may still be viewed. For those software packages that do not process the geotiff tags properly and where the user wishes to georeference the images, a separate georeference report, which contains the necessary information, is available for each image. These reports are in a directory named "georep" under both the "raw" and "enhanced" image directories. The files are called "gloria.txt" and "seamarc.txt." ********************************************** ************************************ DISCLAIMER This Compact Disc-Read Only Memory (CD-ROM) publication was prepared by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, make any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed in this report, or represents that its use would not infringe privately owned rights. Reference therein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. Any views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. Although all data published on this CD-ROM have been used by the USGS, no warranty, expressed or implied, is made by the USGS as to the accuracy of the data and related materials and/or the functioning of the software. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of this data, software, or related materials.