The simulation of a zero-offset section (ZO) from multi-coverage seismic reflection data for a 2-D media, through the stack, is a widely used seismic reflection imaging method, that allows to reduce the amount of data and to improve the signal-to-noise ratio. According to Berkovitch et al. (1999) the Multifocusing method is based on Theory of Homeomorphic Imaging and consists of stacking multi-coverage seismic reflection data with arbitrary distribution source-receiver according to a new local moveout correction, called Multifocusing. This moveout correction is based on a local spherical approximation of the focusing wavefront in the vicinity of the surface of the earth. This method allows to build a seismic section in the domain of the time of a zero-offset increasing the signal-to-noise ratio. The Multifocusing technique does not need any knowledge a priori of the macro-model velocity. Three parameters are used to describe the Multifocusing moveout correction, which are: 1) emergence angle of the zero-offset ray or normal reflection ray (β0), 2) the wavefront curvature at the Point of Normal Incidence (RNIP and 3) the wavefront curvature of Normal Wave (RN). Being also necessary the near-surface velocity. In this thesis work I apply this Multifocusing Stack technique for multi-coverage seismic reflection data covering the models of constant velocity and heterogeneous model, with the objective of simulating of zero-offset sections. In this case as it is the solution of forward problem, this macro velociy model is considered know apriori. In the context of the inverse problem it is had the parameters, RNIP, RN and β0 and can be determining through the analysis of applied coherence to the multi-coverage seismic reflection data. In the solution of this problem the objective function, to be optimized, is defined by the calculation of the maximum existent coherence among the data in the surface of seismic stack. In this thesis we discuss the sensibility of the travetime, used in Multifocusing Stack, as a function of the parameters RNIP, RN and β0. This sensibility analysis is done of three different manners: 1) the first derivate of the objetive function, 2) the coherence measure, denominated semblance, and 3) the sensibility in the Multifocusing Stack.
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