program zyxabc implicit none real, allocatable, dimension (:) :: ux real, allocatable, dimension (:) :: uz real, allocatable, dimension (:) :: sxx real, allocatable, dimension (:) :: szz real, allocatable, dimension (:) :: sxz real, allocatable, dimension (:) :: c11 real, allocatable, dimension (:) :: c13 real, allocatable, dimension (:) :: c33 real, allocatable, dimension (:) :: c44 real, allocatable, dimension (:) :: rho real, allocatable, dimension (:) :: sourcef real, allocatable, dimension (:,:) :: uxsc real, allocatable, dimension (:,:) :: uzsc real, allocatable, dimension (:,:) :: uzs real, allocatable, dimension (:,:) :: uxs real, allocatable, dimension (:) :: mult
Aniso2d - anisotropic modeling
Aniso2d par=Par < Hsourcefn > Hverticalgeophone
velocity model file (c11,c13,c33,c14, and rho ) (next 4 pars from this file
# of z grid points (becomes nz in the program) max=400
# of x grid points (becomes nz in the program) max=400
z grid point spacing (becomes dz in the program)
x grid point spacing (becomes dx in the program) The constants are in order c11,c13,c33,c44,rho and are stored nz(fast) by nx
Source function file (next two pars from this file)
length of source
time sample interval (this will be used for calculations) so it should be within stability limits
number of time steps to run, max=4000
of shots to make (default=1)
Position of first source (in grid points)
vertical force =1; horizontal =2; shear source =3 explosive force=4
shot increment (in x grid points) default=1
Position of first receiver for first shot default=1
Number of receivers default=nx
Shot depth (grid points)
depth of geophones (in grid points)
free surface (default) =1; absorbing =0
number of time steps between snapshots
receiver spread rollalong with the shots? 1=yes=default; 0=no
maximum velocity in model (optional stability check) for stability vpmax*dt/dx <.5 since anisotropic sqrt(max(c11,c33)/rho)*dt/dx <.5 for no dispersion (vmin/fmax)/dx >2.8
is output file for the vertical component seismogram
Program to do anisotropic heterogenous elastic modelling in 2d, explicit finite-difference 2nd order in time 16th order in x and z
seis/model