This is a joint survey by the Institute of Seismology and Vulcanology, Hokkaido University and Institute of Solid Earth Physics, University of Bergen. The survey was conducted from September 9 to September 17, 2002, onboard University of Bergen research vessel "Haakon Mosby". Contents
1. Data and log files
Note 1: EIVA time stamp behaved erraticly - ahead or behind UTC time by several
seconds.
2. Processing of streamer data tapesTriacq streamer recording system stores data on mod. 3480 tape cassettes. Data on a single tape is in Tape Image Format (TIF) - a proprietary Geco format. Reading from a tape results in a single, large TIF file. Data from a single shot is formatted according to the SEG-D Rev. 2 standard. Processing of tapes thus starts with extraction of individual SEG-D formatted shot recordings from the TIF file. The extraction is performed by this program: tifread.cc. The tifread program is part of a shell script that extracts and reads individual SEG-D recordings, before generating a SEG-Y Exabyte tape. The script is here: write_tape.sh. It uses the segdread and segywrite programs in Seismic Unix (Center for Wave Phenomena, Colorado School of Mines). The script makes some assumptions, ref. these comments in the script header: # This script will read the tape image files (*.tif) from disk and write # data in SEG-Y format to a tape. # The files are supposed to be named: 1.tif, 2.tif, 3.tif ... # # A file named ascii.header, which is used as the ebcdic header on the # segy tape, must exist in the current directory. It may be edited # according to your needs (the lines cannot be more than 80 characters # long and the number of lines must be exactly 40).
3. Instrumentation3.1 Block schematics
3.2 StreamerStreamer configuration as of August 22, 2002 (updated by Helge Johnsen).
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