suvelan

来自「seismic software,very useful」· 代码 · 共 28 行

SUVELAN - compute stacking velocity semblance for cdp gathers
suvelan <stdin >stdout [optional parameters]
Optional Parameters:
nv=50                   number of velocities
dv=50.0                 velocity sampling interval
fv=1500.0               first velocity
smute=1.5               samples with NMO stretch exceeding smute are zeroed
dtratio=5               ratio of output to input time sampling intervals
nsmooth=dtratio*2+1     length of semblance num and den smoothing window
verbose=0               =1 for diagnostic print on stderr
Notes:
Semblance is defined by the following quotient:
                n-1
              [ sum q(t,j) ]^2
                j=0
      s(t) = ------------------
                n-1
              n sum [q(t,j)]^2
                j=0
where n is the number of non-zero samples after muting.
Smoothing (nsmooth) is applied separately to the numerator and denominator
before computing this semblance quotient.
Input traces should be sorted by cdp - suvelan outputs a group of
semblance traces every time cdp changes.  Therefore, the output will
be useful only if cdp gathers are input.
Trace header fields accessed:  ns, dt, delrt, offset, cdp.
Trace header fields modified:  ns, dt, offset.