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Miller, J.J.1, Agena, W.F. 1, Lee, M.W. 1, Zihlman, F.N. 1, Grow, J.A. 1, Taylor, D.J. 1, Killgore, Michele1, and Oliver, H.L. 1Open-File Report 01-337
2001
This report is preliminary and has not been reviewed for conformity with the U.S. Geological Survey editorial standards or with the North American Stratigraphic Code. Any use of trade names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
U.S. DEPARTMENT OF THE INTERIOR
U.S. GEOLOGICAL SURVEY
1
U.S. Geological Survey, MS 939, Box 25046, Denver Federal Center, Denver, CO 80225-0046OVERVIEW
This Internet site contains digital seismic data (in SEG-Y format), associated support data, and graphic images (in PDF format), for four regional seismic lines (736 line-miles) recorded in the National Petroleum Reserve – Alaska (NPRA). These lines were created as a supplement to the data set contained on USGS Open File Report 00-286 (Miller et al, 2000) which is a CD-ROM publication that contains stacked, migrated, 2-dimensional seismic reflection data and associated support information for 22 regional seismic lines (3,470 line-miles) recorded in the NPRA from 1974 through 1981. To order the CD-ROM, contact the USGS Earth Science Information Center: 1-888-ASK-USGS (1-888-275-8747) or write to: Box 25286, Building 810, Denver Federal Center, Denver, CO, 80225-0286.
The 22 regional lines contained on the OFR 00-286 form a grid covering the entire NPRA, and were created by combining various individual lines recorded in different years using different recording parameters. The data were reprocessed by the USGS using modern, post-stack processing techniques, to create a data set suitable for interpretation on interactive seismic computer workstations. Reprocessing was done in support of ongoing petroleum resource studies by the USGS Energy Program. The grid of lines has a nominal spacing of 20 x 20 miles. However there are four intervals where the spacing between lines was much greater than 20 miles. To fill these grid spacing gaps, four additional regional lines (736 line-miles) were created using the same techniques as those used to create the lines on OFR 00-286.
Descriptions of, and links to, the files containing the complete report, the seismic data, and the associated support data on this internet site are given below. Additional descriptive information for all the files can be found in the
Metadata-Entity and Attribute Information.1) A file in PDF format (
4RLINES.PDF). This file is the complete Open-File Report and describes the methodology used to create the regional lines, the problems that were encountered, our approach to solving those problems, the processing steps used to create the final seismic sections, the navigation conventions used, and additional details relative to the files contained on this site.2)
Four files containing the digital seismic data in standard, SEG-Y format.3) One ASCII text file containing navigation data (
NPRANAV.SEG) for these 4 lines and for the original 22 lines contained on OFR 00-286, in standard SEG-P1 format;4)
Four small scale graphic images of the four seismic lines in Adobe Acrobat® PDF format;5) A graphic image of the location map (
MAP.PDF), generated from the navigation file,6) An ASCII text file with cross-reference information (
CDP_SP.TXT) for relating the sequential trace numbers on each regional line to the line number and shotpoint number of the original component linesThe PDF files can be opened, viewed, and printed using the free downloadable version of Adobe Acrobat® Reader 4.0, which can be obtained from
http://www.adobe.com.The SEG-Y format seismic files and SEG-P1 format navigation file contain all the information necessary for loading the data onto a seismic interpretation workstation.
Table of graphic images of the seismic lines contained on this internet site with line lengths, and geographic orientation of each line. Click on the line name to display a graphic image in PDF-format of the stacked, migrated record sections.
| Line Name |
Length in Miles (km) |
Orientation |
|---|---|---|
| R-21 |
166 (267) |
N-S |
| R-22 |
210 (338) |
N-S |
| R-23 |
140 (225) |
N-S |
| R-24 |
220 (354) |
E-W |
|
Total: |
736 (1184) |
The PDF-format files can be opened, viewed, and printed using the free downloadable version of Adobe Acrobat® Reader 4.0, which can be obtained from
http://www.adobe.com.Seismic data files in SEG-Y format:
Table of SEG-Y format files of the seismic lines contained on this internet site with file names and file sizes, in bytes. These files are in the SEG-Y seismic data format standard (16-bit integer) that was developed by the Society of Exploration Geophysicists (SEG) in 1975 and has been in common use throughout the geophysical industry since that time. A complete description of the SEG-Y format is given in Barry and others (1975). The files are very large and require special processing software. These files can be downloaded by:
Macintosh: hold down the option key and click with your mouse.
Windows: right click with your mouse.
Line Name |
File Name |
File Size (in bytes) |
|---|---|---|
| R-21 |
R_21.SGY |
25,865,034 |
| R-22 |
R_22.SGY |
42,924,156 |
| R-23 |
R_23.SGY |
21,802,808 |
| R-24 |
R_24.SGY |
34,381,768 |
DISCLAIMER
This Internet site was prepared by an agency of the United States Government. Neither the United States Government nor any agency thereof nor any of their employees makes any warranty, expressed or implied, or assumes any legal 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.
Although all data and software published on this internet site 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 these data, software, or related materials.
SYSTEM REQUIREMENTS
Minimum hardware/software requirements are as follows:
All platforms: Software capable of reading SEG-Y format data files, ASCII text files, and PDF-format files.
REFERENCES CITED
Barry, K.M., Cavers, D.A., and Kneale, C.W., 1975, Recommended standards for digital tape formats, in Digital Tape Standards: Society of Exploration Geophysicists ["Recommended standards for digital tape formats"] reprinted from Geophysics, v. 32, p. 1073-1084; v. 37, p. 36-44; v. 40, p. 344-352, p. 22-30.
Miller, J.J., Agena, W.F., Lee, M.W., Zihlman, F.N., Grow, J.A., Taylor, D.J., Killgore, Michele, and Oliver, H.L., 2000, Regional Seismic Lines Reprocessed Using Post-Stack Processing Techniques: National Petroleum Reserve—Alaska: U.S. Geological Survey Open File Report Open-File Report 00-286, 1 - CD-ROM disk. To order, contact the USGS Earth Science Information Center: 1-888-ASK-USGS (1-888-275-8747) or write to: Box 25286, Building 810, Denver Federal Center, Denver, CO, 80225-0286.
