[Seisunix] Question on time shifting
Juan Diaz-Naveas
I have a line that has time shifts as you can see in the attachment.
When using the surange command the output looks like this
*** begin surange ***
1735 traces:
tracr 10001
fldr 1 1735 (1 - 1735)
tracf 1
cdp 10001
duse 1
swdep 0 114 (75 - 44)
gwdep 0 114 (75 - 44)
scalel -10
scalco -1000
sx -263181195 -263176272 (-263181195 - -263176278)
sy -132172376 -132146214 (-132146214 - -132172376)
gx -263181195 -263176272 (-263181195 - -263176278)
gy -132172376 -132146214 (-132146214 - -132172376)
counit 2
delrt -3 10 (5 - 0)
ns 1000
dt 50
sfs 2750
sfe 14500
slen 3
styp 1
year 2011
day 354
hour 15
minute 34 41 (34 - 41)
sec 0 59 (17 - 31)
shortpad 0 16694 (16624 - 16524)
*** end surange ***
My question is how can I apply the appropriate time shifts in order to get
the clean seismic image.
I recall to have used sustatic in the past, but here this command does not
apply.
Any help will be very much appreciated.
Best wishes
Juan Diaz-Naveas
Wietze Eckhardt
If hdrs=1, then sustatic assumes that header "tstat" contains the time with which the trace is to be shifted. With sign (1 or -1) you control the direction of the shift. (That tstat is used is not very clear from the self-doc, but if you look at the code, you will see.)
Your surange listing doesn't show "tstat", indicating that it is zero for all traces, so sustatic will have no effect.
However, you have "delrt". So if you would assign delrt to tstat and then apply sustatic, you might get what you are after.
You may need to scale from microseconds to milliseconds.
Something like:
suchw key1=tstat key2=delrt b=0.001 < input_data.su | sustatic hdrs=1 sign=-1 > shifted_data.su
Greetings,
Wietze
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Robert Hardy
One way is to copy the delrt headers into the tstat header before you apply sustatic hdrs=1
Another way is to use sushift
I think some of the display programs pick up on delrt header so I normally zero it after applying any shifts...
e.g.
suchw key1=tstat key2=delrt < input.su|sustatic hdrs=1|sushw key=delrt a=0 b=0|suximage
Regards
Rob
________________________________________
From: seisunix...@mailman.mines.edu [seisunix...@mailman.mines.edu] On Behalf Of Juan Diaz-Naveas [jd...@ucv.cl]
Sent: 24 January 2012 12:54
To: seis...@mailman.mines.edu
Subject: [Seisunix] Question on time shifting
Dea SU users,
Best wishes
Juan Diaz-Naveas