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SIO's GeoEel in 2006, using real-time navigation.

    The SIO shipboard computer system inserts an ASCII string containing
the GPS navigation, SeaBeam water depth, and other information into
the Geometrics seismic system (either the StrataVisor or GeoEel).
The Geometrics inserts the string into every SEG-D file as a standard
"External Header".  SIOSEIS automatically detects both the SIO formatted
string and the NMEA standard string and converts the navigation into
hundredths of arcseconds in the SEG-Y format.
    SIOSEIS process geom    type 9   is then able to determine the
shot-to-shot distance automatically.

Step 0 is to verify that the SIO SEG-D header is present and is being
interpreted properly.  Segddin parameter   lprint 32  may be used to
print the SEG-D external header and geom parameter lprint 255 to
print SIOSEIS's interpretation.
Script to generate as much geometry information as possible.
Lots of "printer" output.
The string:
 06-09-06,03:03:11,030310,026 10.9520,-110 24.1460,2.1,207.0,5.9N, 2275.2^M
is the SIO SEG-D external header.

Step 1 is to just plot a shot and analyze.
Script to generate a shot plot.

1)  There are two channel sets because there were two streamers.
Use segddin parameters   fcset 1 lcset 1    to process the 48 channel streamer.
2)  Plot parameter    scalar 0  was used so each trace was normalized.

Step 2 is to check the geometry parameters using geom parameter lprint 2.
Lots of "printer" output.

1)  The ranges are right.
2)  The CDP numbers are right from shot-to-shot.
3)  The CDP (rp) numbers INCREASE down the streamer.  The streamer is
    in front of the ship and being PUSHED.

1)  Use geom parameters:
    rpadd 1000 dbrps -6.25 gxp 1 -100 ggx -12.5 type 9 end
2)  Use    lprint 2   to check the CDP numbering only.
3)  Use    lprint 512  to check that the shot-to-shot distances (DFLS)
           are reasonable.
Correct geometry output.

Step 3 is to further check the geometry by plotting a moved out shot
record with water velocity and see if the water bottom is flat.
Script to generate a shot plot.

1)  Success.  The water bottom is flat.
2)  A couple of traces look noisy.  Replot without AGC and with 
annotation by trace number.

    Plot parameter scalar 0 is used so that the largest amplitude on
every trace is the same size.  Traces 17 and 33 are noisy.  Replotting
with plot parameter    ann shottr    changed to    ann range  shows
that's ranges 300 and 500.  I bet those groups are closest to the
birds.  These traces can be killed.