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. Statics correction corresponds to a time-shift which is applied to seismic trace to eliminate reflections misalignment, caused by topography and weathered layer effects. This correction depends on precise first break picking time determination. Obtain first breaks on seismograms can be a arduous task if data were acquired in complex regions and with low signal to noise ratio. Besides, if the wavelet is generated from a vibroseis source, picking process is even harder once wavelet is non-causalwith energy lobes around the maximum value of the reflection. In the present paper an automatic method to obtain the first breaks picking is proposed, which use complex seismic trace envelope. Picking is performed on shot-gathers corrected from linear moveout, which makes direct and refracted waves horizontal. The first breaks picking method is automatic, stable and reliable for calculation of statics correction. The method was tested using shot-gathers from different sedimentary basin and acquired with explosive and vibroseis source. Results obtained with synthetic and real data show the proposedmethod is robust, numerically stable, computationally efficient and easy to apply. Keywords: automatic picking, static correction, seismic reflection. RESUMO. A correcao estatica corresponde a um deslocamento em tempo, aplicado ao traco sismico, para eliminar a variacao no tempo das reflexoes causada pela variacao da topografia e da camada de intemperismo. Essa correcao depende da determinacao precisa dos tempos das primeiras quebras, processo este denominado de picking . De um modo geral, a primeira quebra esta relacionada com as condicoes proximas a superficie, como o tipo de fonte e a relacao sinal/ruido. Tradicionalmente, a determinacao do sinal que corresponde a primeira quebra foi realizada atraves de uma inspecao visual das amplitudes, e os picking feitos manualmente. Alem de ser muito demorada, essa estrategia pode levar a escolhas tendenciosas e inconsistentes, pois, depende da subjetividade de cada profissional. Com o desenvolvimento de computadores modernos, foram criados softwares de picking automaticos, ainda assim, todo o procedimento ainda e muito demorado e subjetivo. Nesse contexto, e proposto um metodo de picking capaz de determinar, de forma automatica e confiavel as primeiras quebras do sismograma de reflexao para calculo das correcoes estaticas. Os resultados obtidos, sobre dados sinteticos e reais, mostram que o metodo proposto e robusto, computacionalmente eficiente e facil de aplicar. Palavras-chave: picking automatico, correcao estatica, sismica de reflexao.

AUTOMATIC FIRST-BREAKS PICKING USING LINEAR MOVEOUT CORRECTION AND COMPLEX SEISMIC TRACES