SYNOPSIS
PERL PROGRAM NAME:
AUTHOR: Juan Lorenzo (Perl module only)
DATE:
DESCRIPTION:
Version:
USE
NOTES
Examples
SYNOPSIS
SEISMIC UNIX NOTES SUDMOTIVZ - DMO for Transeversely Isotropic V(Z) media for common-offset
gathers
sudmotivz <stdin >stdout cdpmin= cdpmax= dxcdp= noffmix= [...]
Required Parameters:
cdpmin= minimum cdp (integer number) for which to apply DMO
cdpmax= maximum cdp (integer number) for which to apply DMO
dxcdp= distance between adjacent cdp bins (m)
noffmix number of offsets to mix (see notes)
Optional Parameters:
vnfile= binary (non-ascii) file containing NMO interval
velocities (m/s)
vfile= binary (non-ascii) file containing interval velocities (m/s)
etafile= binary (non-ascii) file containing eta interval values (m/s)
tdmo=0.0 times corresponding to interval velocities in vdmo (s)
vndmo=1500.0 NMO interval velocities corresponding to times in tdmo (m/s)
vdmo=vndmo interval velocities corresponding to times in tdmo (m/s)
etadmo=1500.0 eta interval values corresponding to times in tdmo (m/s)
fmax=0.5/dt maximum frequency in input traces (Hz)
smute=1.5 stretch mute used for NMO correction
speed=1.0 twist this knob for speed (and aliasing)
verbose=0 =1 for diagnostic print
Notes:
Input traces should be sorted into common-offset gathers. One common-
offset gather ends and another begins when the offset field of the trace
headers changes.
The cdp field of the input trace headers must be the cdp bin NUMBER, NOT
the cdp location expressed in units of meters or feet.
The number of offsets to mix (noffmix) should typically equal the ratio of
the shotpoint spacing to the cdp spacing. This choice ensures that every
cdp will be represented in each offset mix. Traces in each mix will
contribute through DMO to other traces in adjacent cdps within that mix.
vnfile, vfile and etafile should contain the regularly sampled interval
values of NMO velocity, velocity and eta respectivily as a
function of time. If, for example, vfile is not supplied, the interval
velocity function is defined by linear interpolation of the values in the
tdmo and vdmo arrays. The times in tdmo must be monotonically increasing.
If vfile or vdmo are not given it will be equated to vnfile or vndmo.
For each offset, the minimum time to process is determined using the
smute parameter. The DMO correction is not computed for samples that
have experienced greater stretch during NMO.
Trace header fields accessed: nt, dt, delrt, offset, cdp. User's notes (Juan Lorenzo) untested
CHANGES and their DATES
Import packages
instantiation of packages
Encapsulated hash of private variables
sub Step
collects switches and assembles bash instructions by adding the program name
sub note
collects switches and assembles bash instructions by adding the program name
sub clear
sub cdpmax
sub cdpmin
sub dxcdp
sub etadmo
sub etafile
sub fmax
sub smute
sub speed
sub tdmo
sub vdmo
sub verbose
sub vfile
sub vndmo
sub vnfile
sub get_max_index
max index = number of input variables -1