SUSTATIC - Elevation static corrections, apply corrections from
headers or from a source and receiver statics file
sustatic <stdin >stdout [optional parameters]
Required parameters:
none
Optional Parameters:
v0=v1 or user-
defined
or from header, weathering velocity
v1=user-
defined
or from header, subweathering velocity
hdrs=0 =1 to
read
statics from headers
=2 to
read
statics from files
=3 to
read
from output files of suresstat
sign=1 apply static correction (add tstat
values
)
=-1 apply negative of tstat
values
Options
when
hdrs=2 and hdrs=3:
sou_file= input file
for
source statics (ms)
rec_file= input file
for
receiver statics (ms)
ns=240 number of souces
nr=335 number of receivers
no
=96 number of offsets
Notes:
For hdrs=1, statics calculation is not performed, statics correction
is applied to the data by reading statics (in ms) from the header.
For hdrs=0, field statics are calculated, and
input field sut is assumed measured in ms.
output field sstat = 10^scalel*(sdel - selev + sdepth)/swevel
output field gstat = sstat - sut/1000.
output field tstat = sstat + gstat + 10^scalel*(selev - gelev)/wevel
For hdrs=2, statics are surface consistently obtained from the
statics files. The geometry should be regular.
The source- and receiver-statics files should be unformated C binary
floats and contain the statics (in ms) as a function of surface location.
For hdrs=3, statics are
read
from the output files of suresstat,
with
the same options as hdrs=2 (but
use
no
=max traces per shot and assume
that ns=max shot number and nr=max receiver number).
For
each
shot number (trace header fldr) and
each
receiver number
(trace header tracf) the program will look up the appropriate static
correction. The geometry need not be regular as
each
trace is treated
independently.
Caveat: The static shifts are computed
with
the assumption that the
desired datum is sea level (elevation=0). You may need to
shift
the
selev and gelev header
values
via suchw.
Example: subtracting min(selev,gelev)=25094431
suchw < CR290.su key1=selev,gelev key2=selev,gelev key3=selev,gelev \
a=-25094431,-25094431 b=1,1 c=0,0 > CR290datum.su