[Seisunix] Zero Offset VSP help

Erdi Apatay eapatay at mtu.edu
Tue Aug 25 01:35:50 CEST 2020

Hello All

I have a script I am using for Zero Offset VSP processing. First of all, my
first three traces looked cut so I rejected them. After getting rejected
file, I filtered out the downgoing wavefield by sudipfilt. Then, I picked
arrivals on the zero amplitude line corresponding to picking amplitudes.
Then, I converted those arrival times (seconds) to milliseconds and saving
them in a txt.file. After that, txt file is converted from ascii to binary
format. Finally, I am adding those time values to the traces by
sustatic command.
At this point, however, when I try to plot the flattened upgoings, the
script plots just a so narrow part as follows:
[image: fkfiltflat.PNG]

Can you help me with this issue? I tried to change a lot of things but I
could not get whole flattened upgoings.

 If you would like to check my script, I added here.

Thank you
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set inp = rejected.su

# f-k filtering  
suwind < $inp tmax=3.0 key=gelev | \
#sufilter f=10,20,100,120 amps=0,1,1,0|\
sudipfilt dx=20 dt=0.008 slopes=0.0,0.0002,0.0005 amps=1,0,0 > $inp.fkfilt.su

#Adding first arrival times
sushw key=d1 a=1000 < $inp | suxwigb xcur=.5 mpicks=pickfile_20_sources_B1_milisec.txt
a2b < pickfile_20_sources_B1_milisec.txt n1=2 > rejected_fa.bin 
b2a < rejected_fa.bin > tmp.ascii 
sushw < $inp.fkfilt.su infile=rejected_fa.bin key=tstat,tracf |\
sustatic hdrs=1 sign=-1 > $inp.fkfilt.flat.su 

#Generating corridor stack
sustack < $inp.fkfilt.flat.su key=cdp repeat=1 nrepeat=10 > $inp.stacked.su

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