Specular multiple from dipping water-bottom

I presented the particular case of flat water bottom case in some detail because it lends itself to the nice closed-form equation for the residual moveout of the multiples in ADCIGs. This equations is the basis for the design of the Radon transform to attenuated the multiples. The specular multiple from a dipping water-bottom has similar characteristics although the moveout equations are more involved (, ) and will not be given here. Instead, I show in Figure 5 the zero subsurface offset section, an SODCIG and its corresponding ADCIG. The lines superimposed are the moveout curves computed with the equations in (). The zero subsurface-offset section corresponds to a reflector with twice the dip of the water-bottom. The ADCIG has its apex at zero aperture angle.

wb-dip-moveout
Figure 5. Specular multiple from dipping water-bottom. Panel (a) is the zero subsurface-offset section. Panel (b) is an ODCIG and panel (c) is its corresponding ADCIG. The solid lines are the moveout curves computed with the equations given by ().