In this work, a new tomographic reflection inversion method is studied, with the objective
of determining smooth and isotropic velocity models for real and synthetic seismic data. The
velocity model is obtained by the program NIPTOMO, which is an implementation of a
tomographic inversion method of the kinematic attributes of the hypothetical waves NIP (normal
incidence point). The input data for the tomographic inversion, e. g., traveltime tables and NIP
attributes (wavefront curvature radius and emergence angle) are obtained through a set of picked
points on a simulated zero-offset (ZO) section, previously obtained by the common-reflection
surface (CRS) method. The choice of picked points in a ZO section is normally made using
automatic picking programs that identify locally coherent events in a seismic section, based in
user-defined parameters. The picking process is one of the most critical steps in this new method,
since the choice of non primary reflection events, such as diffractions and multiples, may lead to
errors in the velocity model obtained by the tomographic inversion. This work has as main
objective develop an interative picking program to give to the user the control of the choice of
primary reflection points that are used as input for the tomographic inversion. The present
picking program was tested on the synthetic Marmousi dataset and on a real data from the Tacutu
Basin, Brazil (seismic line 50-RL-90). The results obtained show that the interative picking
process for the choice of primary reflection events points favors the determination of a precise
velocity model.
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