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sioseis << !
procs segdin prout geom header output diskob gather nmo gains smute stack despike diskoa end
segdin
ffilen 99999 # take all shots (this is the preset!)
ftr 1 ltr 160 # skip the auxiliary channels - 161-172 and 161-180
secs 16.0 # DMS-2000 has garbage from the even second to the end
decimf 2 # decimate from 2 to 4 ms. Little energy above Nyquist!
offline yes # eject after the rewind after EOT
tr0 yes # write trace 0 to tape
newfile yes # start a new SEG-Y file on every SEG-D tape
iunit 3 end
end
geom
# shot spacing of 50 m (dfls), 12.5 m cdp bins, 25 group spacing
# range to closest trace varies.
# bird/depth sensors change on every deployment
bgp 1 5 3 9 4 17 5 25 6 33 7 41 9 45 10 53 11 65 12 73
13 85 14 98 15 106 16 118 17 125 18 133 8 141 2 149
type 2 # increment the shot loaction based on the shot number
fs 1 ls 999999 # all shot have the same parameters (preset)
gxp 160 -138 # RESET the closest group only.
ggx -25 # Used to extrapolate gxp!
dfls 50.0 dbrps 12.5 smear 12.5 end
end
despike
fac 5 end # Sutton/Trehu far-close average
end
output
ontrcs 160 # reinforce that only 160 traces are to be written
rewind 0 # leave the tape alone!
ounit 4 end
end
header
# geom started the line with negative rp numbers which some processes
# don't like, so make them positive right away!
l6 l6 + 200 fno 1 lno 9999999 end
end
smute # "inner" mute
addwb yes # add in the water bottom time
fno 1 lno 999999 xsets 163 1 16 2163 16 16 interp on end
end
diskob
# write every 15th shot to a "circular" file
fno 1 lno 999999 noinc 15 rewind 1 opath shot.file end
end
gather
# Scratch file parameters, really 2250 4 byte wrds, maxtrcs of 40, pad to be safe
# Roughly 150 MB scratch file
maxrps 170 nwrds 4400 maxtrs 50 end
end
gains
# Do spherical divergence.
# alpha .4 means range 263 is multiplied by 9, range 4263 by 30
# type 8 alpha .4 end
# alpha .5 means range 263 is multiplied by 15.7, range 4263 by 68.4
type 8 alpha .5 end
end
nmo
# real time nmo, replace interpolation by RP to WB depth in Meters.
# If water depth changes by > 100 m, use previous value. Water-depth
# velocity functions supplied by Trine, interpolation by iso-velocity layering
vtrkwb 1000 stretc 0.06
fno 387 lno 387 vtp 1475 0.516
1623 0.867
1716 0.961
2022 1.272
2149 1.523
4029 3.007
4536 3.446
5375 4.385
6652 10.01 end
fno 542 lno 542 stretc .06 vtp 1475 0.722
1912 1.423
2039 1.689
5537 3.935
6795 10.01 end
fno 1021 lno 1021 stretc .065 vtp 1475 1.361
1926 1.967
2074 2.201
2195 2.340
5537 4.352
6716 10.01 end
fno 1475 lno 1475 stretc .07 vtp 1475 1.967
1761 2.373
1797 2.506
1878 2.640
2018 3.101
2047 3.340
2334 3.501
2880 3.646
5156 4.191
5715 5.325
6609 10.01 end
fno 1688 lno 1688 stretc .075 vtp 1475 2.251
1696 2.862
1789 3.123
1912 3.301
2273 3.568
2736 3.846
3322 4.118
5024 5.441
6275 10.01 end
fno 1721 lno 1721 vtp 1475 2.295
1535 2.612
1598 2.784
1659 3.018
1687 3.085
1772 3.318
1828 3.459
2014 3.635
2648 4.046
2822 4.135
4962 6.008
5537 6.725
6248 10.01 end
fno 1817 lno 1817 stretc .08 vtp 1475 2.423
1561 2.990
1634 3.163
1659 3.296
1721 3.401
1792 3.596
2065 3.879
2621 4.352
2892 4.635
5156 5.975
6207 10.01 end
fno 1871 lno 1871 vtp 1475 2.495
1584 2.918
1617 3.035
1636 3.212
1677 3.451
1721 3.596
1836 3.663
1895 3.718
1990 3.796
2321 4.141
2845 4.250
3686 4.597
5299 6.681
6118 10.01 end
fno 1995 lno 1995 stretc .09 vtp 1475 2.660
1555 3.193
1591 3.346
1708 3.760
1792 4.020
1989 4.392
2131 4.633
2309 4.879
2784 5.126
3718 6.513
4139 7.279
4472 8.526
5845 10.01 end
fno 2239 lno 2239 stretc .1 vtp 1475 2.986
1551 3.626
1618 3.866
1708 4.212
1776 4.366
1845 4.559
1940 4.719
2043 4.886
2243 5.079
2744 5.392
2794 5.492
6138 10.01 end
fno 2434 lno 2434 vtp 1475 3.246
1533 3.792
1571 3.959
1585 4.132
1624 4.259
1734 4.479
1766 4.606
1842 4.746
1882 5.052
1950 5.306
2320 5.412
2764 5.759
3954 8.999
5545 10.01 end
fno 2574 lno 2574 vtp 1475 3.433
1672 4.572
1743 4.786
2096 5.452
2338 5.692
3204 6.559
5933 10.01 end
end
prout
# print the stacked trace number just so the light blink!
fno 0 lno 99999 ftr 1 ltr 1 end
end
diskoa
# Write out disk file
opath stacked/stack.line4 end
end
end
!
Go to the list of seismic processes.
Go to SIOSEIS introduction.