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MIGRATION EQUATION FOR COMMON MIDPOINT SLANT STACK

According to Ottolini 1982, the DSR equation for the downward continuation of common midpoint slant stack is  
 \begin{displaymath}
{\partial u \over \partial z }
= {{-i\omega \over v} \left[\sqrt{1-(Y+pv)^{2}}+\sqrt{1-(Y-pv)^{2}}\right ]U}\end{displaymath} (2)
where

\begin{displaymath}
Y = {{vk_{y} \over 2\omega}} \end{displaymath}

The solution of equation (2) is  
 \begin{displaymath}
U(\omega,z+\Delta z,k)=U(\omega,z,k){\exp \left\{{ {-i\omega...
 ...1-({vk_{y} \over 2\omega}-pv)^{2}}\right ]\Delta z} \right \} }\end{displaymath} (3)
We can use this equation to obtain the wave extrapolation for constant velocity. Velocity variations in depth are easily accommodated by varying the velocity v with depth z in equation (3).


\begin{picture}
(16,8)(0.,-2.)
\vspace{4cm}
\put(6,6){\makebox[3cm]
{$U(\omega,z...
 ...[3cm]
{$U(\omega,z+\Delta z,k)$}}
\put(7.8,-3.7){\vector(0,-1){.7}}\end{picture}

*2cm

 
dum
dum
Figure 1
Computational flow chart of prestack slant stack migration with one-pass PSPI.


previous up next print clean
Next: IMPLEMENTATION FOR LATERAL VELOCITY Up: Lin: Prestack PSPI Previous: SLANT STACK TRANSFORMATION
Stanford Exploration Project
11/17/1997