Análise de imageamento sísmico em ambientes carbonáticos carstificados

Abstract

Currently, the degree of detail in the images is essential to the interpretation of data from seismic reflection surveys. To obtain such a level of detail, a good acquisition stage and a good processing stage of this data are essential. Since more than 60\% of oil and gas reservoirs in the world are of carbonate origin, there is a commitment by the oil and gas industry to characterize these reservoirs, which are still considered complex. Taking into account that carbonate rocks have high seismic wave propagation velocities and a greater susceptibility to diagenetic changes compared to reservoirs of siliciclastic origin. One of the factors driving the industry to investigate carbonate reservoirs is the possible accumulation of oil at interfaces with a high degree of dissolution (karst), which can have a positive impact on this type of reservoir. In this research, a one-step approach to the processing of seismic reflection data was carried out with the elaboration and application of a pre-stack Kirchhoff migration code in the depth domain using the ray tracing technique. Imagement tests were carried out using synthetic models analogous to karstified carbonate environments, tests that proved to be effective in the precise identification of supposed karst regions with good resolution, contributing to increased understanding of this type of environment.