HOME | CONTENTS | GEOLOGIC DISCUSSION | DATA/GIS | METADATA | REFERENCES | CONTACTS

Table of Contents:

OF 2004-1014

Disc Contents

Geologic Discussion

Data/GIS

• Getting Started

• Navigation

• Seismic-reflection

• Sidescan-sonar mosaics

• Ground-Truthing

Metadata/Data
    Catalog

References Cited

Contacts

SEISMIC-REFLECTION

These seismic-reflection data files are binary encoded SEG-Y format and cannot be viewed directly. The SEG-Y files may be processed and plotted with seismic processing software such as Seismic Unix (http://www.cwp.mines.edu/cwpcodes/index.html) and SIOSEIS (http://sioseis.ucsd.edu/). To download a SEG-Y file, click on the filename with the right mouse button. Depending upon the browser being used, you can either "Save this link as " or "Save target as " to save the file to a location on the hard drive. These files can also be copied directly from the DVD under the directory data/segy.

For convenience, downsampled JPEG images are available for viewing the data. Clicking on the thumbnail image of the seismic-reflection profile will link to a larger image of the seismic data for that particular file in a separate window. In each of the seismic profiles, the units of the x-axis are shot points, the y-axis is two-way travel time in milliseconds. The JPEG images can be downloaded in a variety of ways. To acquire an individual image, click on the thumbnail image which will link to a larger image. In Internet Explorer, right click on this image and select "Save image as...". The individual images can also be copied from the DVD directly from the data/seisimages directory. To acquire a WinZip file of all the seismic images, either go to the Metadata/Data Catalog page, or click on seisimages and save the "zipped" file to a preferred location and uncompress it.

The SEG-Y files on the DVD conform to the SEG-Y standard format (Barry and others, 1975). The SEG-Y standard consists of the following:

• A 3600-byte reel identification header with the first 3200 bytes consisting of an EBCDIC header block and a 400-byte binary header block. Both headers include information specific to line and reel number.

• The trace data block follows the reel identification header. The first 240 bytes of each trace block is the binary trace identification header. The seismic data samples follow the trace identification header.

***The navigation recorded in the header of the SEG-Y files is UTM, Zone 11, NAD83. The survey area actually straddled the boundary between UTM zones 10 and 11, but for consistency, navigation was written to all the headers as zone 11.

FILE: l1f1 1278 traces:

Start of file: l1f1 SHOT=1 day=260 hour=17 minute=52 sec=56

End of file: l1f1 SHOT=1278 day=260 hour=18 minute=9 sec=59

FILE: l2f1 6369 traces:

Start of file: l2f1 SHOT=1 day=260 hour=18 minute=15 sec=0

End of file: l2f1 SHOT=6369 day=260 hour=19 minute=40 sec=17

FILE: l2f2 6208 traces:

Start of file: l2f2 SHOT=1 day=260 hour=19 minute=40 sec=53

End of file: l2f2 SHOT=6208 day=260 hour=21 minute=3 sec=57

FILE: l3f1 12273 traces:

Start of file: l3f1 SHOT=1 day=260 hour=21 minute=8 sec=14

End of file: l3f1 SHOT=12273 day=260 hour=23 minute=52 sec=31

FILE: l4f1 11880 traces:

Start of file: l4f1 SHOT=1 day=261 hour=20 minute=33 sec=17

End of file: l4f1 SHOT=11880 day=261 hour=23 minute=12 sec=16

FILE: l5f1 5266 traces:

Start of file: l5f1 SHOT=1 day=261 hour=23 minute=20 sec=12

End of file: l5f1 SHOT=5266 day=261 hour=0 minute=30 sec=40

FILE: l6f1 14256 traces:

Start of file: l6f1 SHOT=1 day=262 hour=16 minute=13 sec=46

End of file: l6f1 SHOT=14256 day=262 hour=19 minute=24 sec=32

FILE: l7f1 9098 traces:

Start of file: l7f1 SHOT=1 day=262 hour=19 minute=28 sec=14

End of file: l7f1 SHOT=9098 day=262 hour=21 minute=29 sec=58

FILE: l8f1 805 traces:

Start of file: l8f1 SHOT=1 day=263 hour=17 minute=46 sec=57

End of file: l8f1 SHOT=805 day=263 hour=17 minute=57 sec=24

FILE: l9f1 851 traces:

Start of file: l9f1 SHOT=1 day=263 hour=18 minute=3 sec=36

End of file: l9f1 SHOT=851 day=263 hour=18 minute=11 sec=6

FILE: l10f1 586 traces:

Start of file: l10f1 SHOT=1 day=263 hour=18 minute=17 sec=48

End of file: l10f1 SHOT=586 day=263 hour=18 minute=23 sec=0

FILE: l11f1 728 traces:

Start of file: l11f1 SHOT=1 day=263 hour=18 minute=27 sec=23

End of file: l11f1 SHOT=728 day=263 hour=18 minute=33 sec=48

FILE: l12f1 741 traces:

Start of file: l12f1 SHOT=1 day=263 hour=18 minute=37 sec=35

End of file: l12f1 SHOT=741 day=263 hour=18 minute=44 sec=12

FILE: l13f1 737 traces:

Start of file: l13f1 SHOT=1 day=263 hour=18 minute=47 sec=17

End of file: l13f1 SHOT=737 day=263 hour=18 minute=53 sec=49

FILE: l14f1 681 traces:

Start of file: l14f1 SHOT=1 day=263 hour=18 minute=58 sec=8

End of file: l14f1 SHOT=681 day=263 hour=19 minute=4 sec=10

FILE: l15f1 726 traces:

Start of file: l15f1 SHOT=1 day=263 hour=19 minute=8 sec=9

End of file: l15f1 SHOT=726 day=263 hour=19 minute=14 sec=37

FILE: l16f1 754 traces:

Start of file: l16f1 SHOT=1 day=263 hour=19 minute=20 sec=14

End of file: l16f1 SHOT=754 day=263 hour=19 minute=26 sec=54

FILE: l17f1 768 traces:

Start of file: l17f1 SHOT=1 day=263 hour=19 minute=32 sec=21

End of file: l17f1 SHOT=768 day=263 hour=19 minute=39 sec=8

FILE: l18f1 815 traces:

Start of file: l18f1 SHOT=1 day=263 hour=19 minute=42 sec=26

End of file: l18f1 SHOT=815 day=263 hour=19 minute=49 sec=39

FILE: l19f1 766 traces:

Start of file: l19f1 SHOT=1 day=263 hour=19 minute=53 sec=37

End of file: l19f1 SHOT=766 day=263 hour=20 minute=0 sec=24

FILE: l20f1 801 traces:

Start of file: l20f1 SHOT=1 day=263 hour=20 minute=6 sec=23

End of file: l20f1 SHOT=801 day=263 hour=20 minute=13 sec=29