sumigpreffd.su.main

su 的源代码库

SUMIGPREFFD - The 2-D prestack common-shot Fourier finite-difference	
			 migration.					

  sumigpreffd <indata >outfile [parameters]				", 

 Required Parameters:							",  
 nxo=	   number of total horizontal output samples			
 nxshot=	number of shot gathers to be migrated			
 nz=		number of depth sapmles					
 dx=		horizontal sampling interval				
 dz=		depth sampling interval					
 vfile=	 velocity profile, it must be binary format.		
  
 Optional Parameters:							
 fmax=25	the peak frequency of Ricker wavelet used as source wavelet
 f1=5,f2=10,f3=40,f4=50	 frequencies to build a Hamming window	
 lpad=9999,rpad=9999		number of zero traces padded on both	
 sides of depth section to determine the migration aperature, the default", 
 values are using the full aperature.				   	
  
 Notes:								
 The input velocity file consists of C-style binary floats.		",  
 The structure of this file is vfile[iz][ix]. Note that this means that
 the x-direction is the fastest direction instead of z-direction! Such a
 structure is more convenient for the downward continuation type	
 migration algorithm than using z as fastest dimension as in other SU  ", 
 programs.								

 Because most of the tools in the SU package (such as  unif2, unisam2, ", 
 and makevel) produce output with the structure vfile[ix][iz], you will
 need to transpose the velocity files created by these programs. You may
 use the SU program \'transp\' in SU to transpose such files into the  
 required vfile[iz][ix] structure.					



 Credits: CWP, Baoniu Han, [e-mail], April 19th, 1998


 Trace header fields accessed: ns, dt, delrt, d2
 Trace header fields modified: ns, dt, delrt