Estimation of kinematic wavefront characteristics and their use for multiple attenuation

Kinematic wavefront characteristics of primary reflected waves can be used to predict and attenuate surface-, as well as interbed multiples. In order to estimate kinematic wavefront characteristics directly from unstacked dat a the common-shot-point homeomorphic-imaging (CSP HI) method can be applied . This macro-model-independent method is based on a new local moveout corre ction that depends on two wavefront parameters: the emergence angle and the radius of wavefront curvature of a reflected primary wavefront. These para meters can be estimated by optimizing the semblance correlation measure, ca lculated in the common-shot-gather along the travel time curve defined by t he new moveout correction. In the case of local maxima in the semblance fun ctional, an automatic maximization procedure might lead to a wrong estimati on of these parameters. In order to avoid such a situation we propose an in teractive, horizon-based implementation of the CSP HI method, which allows manual picking of the optimal wavefront parameters along the seismic line. Afterwards, we use the estimated emergence angles for the prediction and at tenuation of multiples, based on the simple but powerful idea that any mult iple event can be represented as a combination of primaries. A synthetic ex ample shows the viability of the parameter estimation, prediction and atten uation procedure. (C) 1999 Elsevier Science B.V. All rights reserved.