EW0210 watch seismic processing – 13 October 2002

The watch is expected to perform two seismic processing tasks:

1) Copy each 3490 tape to DLT tape.

2) Monitor the real-time stack. Start/stop the stack on line changes.

1) 3490 to DLT tape copy (also reformats from SEG-D to SEG-Y). This is done on computer heezen. Use user name sioseis and password sioseis. The copy script is: heezen:/data/seisnet/0210/copy/copy. The script writes to two DLTs AND to the UWYO raid on computer tanaga. The script also writes every 20^th shot to disk (heezen:/data/0210/shots/latest.shot).

The script may run continuously except when the line changes so a new disk file can be created AND after 55 3490 tapes have been written to the DLT. In both cases, the script may be terminated with control-c. The copy script has one argument: line-name. copy line-name

E.G. copy 1a

When 55 tapes have been written to DLT, kill the tape copy job with a control-c. Rewind and remove both DLTs, remembering to write protect both of them.

2) The real-time stack reads every shot from the “seisnet” system, processes it, and writes a few traces to the Atlantek plotter. The seisnet/sioseis stack script(s) should be run on computer grampus. The stack requires three separate processes: A) A connection between seisnet and sioseis. B) The sioseis stack script. C) A process plotting the traces created by sioseis. Use grampus user name seisnet and password pass123. The stack directory is: /export/home3/seisnet/0210/brute.

A) Start the connection between seisnet and sioseis in it’s own window. The only argument to the script is the last subdirectory name where the shot files are written on the seisnet computer. init_seisnet directory-name e.g. init_seisnet line1a

B) The stack script has two arguments, the line name and the direction of the plot. The plot direction convention is that the North or East end of the seismic plot should be on the right hand side. When sailing to the west (course 270), the first shot is in the east and the plot direction should be “rtl”.

Courses 315-360, 0-135 are ltr

Courses 135-315 are rtl

E.G. stack line1a rtl

C) The program atlantek uses the plot filename as an argument. The stack plot files are in grampus:/export/home3/seisnet/0210/stack_plots. E.G. atlantek line1a.atlantek

At the end of the seismic line, stop the stack script by entering control-c in the init_seisnet window, followed by typing the word alto. Alto signals sioseis that no more data is available and it flushes the gather, stack, and plot buffers. When the stack script terminates with the words “END OF SIOSEIS RUN”, the atlantek program may be terminated with a control-c.