U.S. DEPARTMENT OF THE INTERIOR / U.S. GEOLOGICAL SURVEY U.S. GEOLOGICAL SURVEY DIGITAL DATA SERIES DDS-13 International Phase of Ocean Drilling Seismic Line 1 Demultiplexed Data Cape Hatteras to Mid-Atlantic Ridge OVERVIEW INTRODUCTION This CD-ROM is part of a 39 disc collection containing the demultiplexed seismic data from a 3400 km-long multichannel seismic-reflection profile extending from Cape Hatteras, N.C., to the rift valley of the Mid-Atlantic Ridge. The data were collected in 1974 as part of the International Phase of Ocean Drilling (IPOD) which was jointly funded by the U.S. Geological Survey (USGS) and the National Science Foundation's Deep Sea Drilling Project (DSDP). Each disc in the collection contains: * Binary files of SEG-Y format demultiplexed seismic data for a portion of the profile. Please see DATA, below, for a description of the data on disc. * Graphic image files of the original observers' logs kept during data acquisition. Please see OBLOGS, below, for more information. * A text file of shotpoint locations and a graphic image of a figure illustrating those locations. Please see NAVIGATION, below, for more information. * DOS-based software allowing: - interactive display of the SEG-Y demultiplexed data. - interactive display of the observer's logs graphic images. - interactive SEG-Y data review and editing. Please see SOFTWARE, below, for more information. * Documentation. Please see DOCUMENTATION, below, for more information. This CD-ROM has been produced in accordance with the International Standards Organization (ISO) 9660 standard. The data and text files can be read by any platform having CD-ROM driver software that supports this standard. DOS SOFTWARE INSTALLATION 1 The software on disc may be used from the DOS command line or through a menu system which may be installed. To run the software from the command line, use the programs as described by the appropriate documents. Please see SOFTWARE, below. In order to install the menu system: * Place the CD-ROM in the CD-ROM reader. * Make the CD-ROM reader the current working directory. * Type INSTALL. This will place a file named DDS13.BAT in a user-specified directory, which will execute the menu system. To use the menu system, make that user-specified directory the current working directory and type "DDS13" at the DOS command line. This information is repeated in the documentation file GETSTART.TXT. MINIMUM DOS SYSTEM REQUIREMENTS The minimum DOS system requirements to use the data and display software are as follows: * IBM or compatible personal computer, having an 80286 or higher numbered processor. An 80386 or higher is recommended. * 512 kb RAM. * MS- or PC-DOS version 3.1 or later. * Microsoft MSCDEX version 2.1 or later. * CD-ROM drive with ISO 9660 software driver. * EGA, VGA, or Hercules graphics system. DISC DIRECTORY STRUCTURE Each disc has the following directory structure: AVIION contains DUMPSEGY compiled for a Data General Aviion work station. DOCFILES contains ASCII text files of documentation. NAV contains an ASCII text file of shotpoint information and a graphic image of a shotpoint location figure. OBLOGS contains graphic image files of observers' logs for the data on disc. 2 SEGY contains binary SEG-Y format seismic data files. SOFTWARE DOS-based data display and utility software. DATA Each file of seismic data is the disc-image of a SEG-Y format tape output during the demultiplexing of the original field data. The data were written to tape using the 32 bit IBM floating point format (Barry and others, 1975). As the data were copied bit-for-bit to the CD-ROM file, this format was preserved. Each file of sesimic data is named IPD{number}, where {number} is the first shotpoint in the file. Please see PROCESS.TXT for a description of the demultiplexing process and the magnetic tapes created. 3 OBLOGS The original observers' logs kept during data acquisition were scanned into graphic image files, so those documents could be perserved abd distributed along with the data. Each disc contains, scanned into digital form, the appropriate sheets of the observers' logs for the data on that disc. Each file represents one sheet of the observers' logs. Each file is named OB{number}.{format}, where {number} is the first shotpoint on that sheet and {format} is the graphics format used. Each sheet of the observers' logs is stored in 3 different graphic image formats: PCX, TIFF, and GIF. Files are named OB{number}.PCX, OB{number}.TIF, and OB{number}.GIF. Included on disc is a DOS- based PCX image viewer. Please see OBPLOT.TXT for a description of the DOS-based PCX image viewer. NAVIGATION Shotpoint locations for the entire IPOD Seismic Line 1 are given in decimal degrees, 6 digit precision, in an ASCII text file named NAV.TXT in the NAV subdirectory. Location information starts with the first shotpoint of the line and is then given for every 10th shotpoint. SOFTWARE PLOTSEIS is a DOS display program allowing the user to review the actual SEG-Y data and obtain hard copy using the DOS Print Screen function. In order to run PLOTSEIS, either start it from the menu system provided, or change directory to the SEGY subdirectory and type PLOTSEIS, and respond to the program's prompts. The user may accept the default values presented by PLOTSEIS or enter new ones. Please see PLOTSEGY.TXT and PSGYNEWS.TXT in the DOCFILES subdirectory for a description of program usage. DUMPSEGY is a DOS seismic data utility allowing the user to examine all the components of the SEG-Y data files: the EBCDIC and binary headers, the individual data-trace headers, and the hexadecimal SEG-Y samples composing a data trace, or their actual floating-point values. In order to run DUMPSEGY, change directory to the SEGY subdirectory and at the DOS prompt type DUMPSEGY followed (after a space) by the file name desired and any program options. Typing DUMPSEGY by itself will display a usage screen informing the user how to use the program. Please see DUMPSEGY.TXT and DSGYNEWS.TXT in the DOCFILES subdirectory for a description of program usage. OBPLOT is a DOS utility to view and manipulate PCX format graphic image files. This utility allows displaying the PCX format observers' logs and shotpoint location figure on this disc. 4 Please see OBPLOT.TXT in the DOCFILES subdirectory for a description of program usage. DOCUMENTATION Documentation files on disc: A_README.TXT A short description of this data set. ACKNOWL.TXT Acknowledgments to people helpful in creating his data set. AUTHORS.TXT Authors of this data set. CONTACTS.TXT Contacts for more information the data and software included in this data set. DISCnn.TXT Description of specific seismic data and observers' logs on each individual disc. The "nn" represents the disc number of the data set, 1 to 39. DISCLAIM.TXT USGS disclaimer. DUMPSEGY.TXT Documentation for the seismic data utility DUMPSEGY. DSGYNEWS.TXT DUMPSEGY update to the original documentation described above. GETSTART.TXT A brief description of installing the DOS-based menu system. NAV.TXT ASCII text file of shotpoint location information. OBPLOT.TXT documentation for the DOS observers' logs viewing program. OVERVIEW.TXT This file. PLOTSEGY.TXT Documentation for the DOS seismic data viewing program PLOTSEIS. 5 PSGYNEWS.TXT PLOTSEIS update to the original documentation described above. PROCESS.TXT Description of the demultiplexing of the original field data. REFERENC.TXT References used in all documnetation files. TITLE.TXT Title of this data set. 6 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 the 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. Although all data and software 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 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. 7 REFERENCES Barry, K.M., Cavers, D.A., and Kneale, C.W., 1975, Recommended standards for digital tape formats: Geophysics, v. 40, p. 344-352. 8