Residual Moveout in ADCIGs

In this appendix I show that, for a flat reflector, the residual
moveout of the multiples in ADCIGs reduces to the tangent-squared
expression derived by Biondi and Symes (2004) for the residual
moveout of under-migrated primaries:

where is the normal-incidence migrated-depth, (

There is an important and unfortunate
difference in notation here, however, because in equation A-1
is the ratio of the migration to the true *slowness*
whereas in equation A-2 is the ratio of the migration to the true
*velocity*. Therefore, in order to get a better idea of how the approximation
for the RMO of the multiples (accounting for ray bending at the reflector
interface) relates to that of the primaries (neglecting ray bending), I rewrite
equation A-2 replacing by and
with
to get:

For small , and , therefore

(11) |

2007-10-24