Program sfrtm2d | 2-D zero-offset reverse-time migration
[SYNOPSIS]
sfrtm2d vel=modl.rsf < data.rsf > imag.rsf adj=n n0=0 nt= dt=
[PARAMETERS]
bool    | adj | =n |  [y/n] | 	if y, migration; else, modeling 
float   | dt | = |   | 	time sampling interval: dt 
int     | n0 | =0 |   | 	shot depth in the grid 
int     | nt | = |   | 	number of time steps 
file    | vel | = |   | 	auxiliary input file name
[DIRECTORY]
user/pyang
