# On the dynamics of interbed multiples

Thursday, October 20, 2005 - 10:20am - 11:10am

EE/CS 3-180

Fons Ten Kroode (The Shell Group)

Interbed multiples form a class of multiples in seismic data characterized by the property that all reflection points lie in the

subsurface. This sets them apart from surface multiples, which have at least one reflection point at the surface of the earth.

For surface multiples there is a well established procedure to predict them from the data, i.e. without any a-priori knowledge of

the subsurface. This procedure is firmly based on the wave equation and is exact from a theoretical point of view.

For interbed multiples the situation is much less satisfactory. In 1997 Art Weglein published an algorithm to predict them from the

data. This algorithm is clearly a generalization of the surface related case, but its derivation is not. In fact, the algorithm

initially came without a formal proof. I have tried to fill that gap in a 2001 paper, by providing a derivation based on weak

scattering and asymptotics. This derivation demonstrated that the kinematics of Wegleinxs algorithm are correct, but at the same

time left open the question of the dynamics. Since then I have obtained results for the dynamics by replacing the weak scattering

assumption by the Kirchhoff scattering assumption.

In the presentation I will explain how to obtain prediction algorithms for interbed multiples under the weak scattering and

Kirchhoff scattering assumptions.

subsurface. This sets them apart from surface multiples, which have at least one reflection point at the surface of the earth.

For surface multiples there is a well established procedure to predict them from the data, i.e. without any a-priori knowledge of

the subsurface. This procedure is firmly based on the wave equation and is exact from a theoretical point of view.

For interbed multiples the situation is much less satisfactory. In 1997 Art Weglein published an algorithm to predict them from the

data. This algorithm is clearly a generalization of the surface related case, but its derivation is not. In fact, the algorithm

initially came without a formal proof. I have tried to fill that gap in a 2001 paper, by providing a derivation based on weak

scattering and asymptotics. This derivation demonstrated that the kinematics of Wegleinxs algorithm are correct, but at the same

time left open the question of the dynamics. Since then I have obtained results for the dynamics by replacing the weak scattering

assumption by the Kirchhoff scattering assumption.

In the presentation I will explain how to obtain prediction algorithms for interbed multiples under the weak scattering and

Kirchhoff scattering assumptions.