Salt Stratification and Least Square Migration to Improve Pre-Salt Reservoir Images: Santos Basin, Brazilian Offshore Example

Abstract

Summary This paper presents the benefits of combining geological velocity modelling with Least-Squares Migration to generate seismic images for the Brazilian presalt reservoirs. The geological velocity modelling focus on the evaporitic salts section characterization, regarding the stratification features presented on this layer, which were incorporated in the velocity model. Results are compared with seismic images created by the velocity model with tomography – without salt stratification – and Reverse Time Migration. In addition, a quantitative comparison is made with a modelled reference horizon to analyse the depth positioning and the migrated amplitude.