Seismic amplitude inversion for interface geometry: practical approach for application (original) (raw)

This paper presents a practical approach for the application of real seismic amplitude data in the context of re£ection seismic tomography. The estimation of recorded seismic amplitudes from re£ection seismic gathers is performed with the aid of pre-stack time migration, which enhances continuity and re£ection strength and reduces re£ection point dispersal and di¡raction e¡ects. Moreover, contraction of the Fresnel zone by migration brings the amplitudes closer to the ray amplitudes assumed in the inversion. De-migration of the amplitudes follows, so that we recover a set of`true' observations for input to inversion. To make the amplitude inversion robust, the e¡ect of noise in the amplitude data is mitigated by applying iteratively a locally reweighted regression, which can e¤ciently reject amplitude outliers. This approach is applied to a re£ection seismic pro¢le from the North Sea to constrain the geometry of a stack of interfaces by using both the amplitude inversion and a joint inversion with traveltime data. The application example represents a valuable contribution to the discussion of how the combined e¡ort of imaging and inversion of seismic data should be organized when we are dealing with ¢eld data.