Análise sismoestratigráfica do intervalo Cretáceo Superior / Terciário, registrado no sudoeste da Bacia de Santos

Abstract

Nowadays, the exploration of non-renewable resources requires a much more accurate geological knowledge, as it is the case of oil exploration where each day the geological challenges increase with the complexity of the plays. This is why the integration of various tools can increase the probability of success on the road to new discoveries. With the implementation of seismostratigraphic interpretation techniques and stratigraphic sequences to the analysis of sedimentary basins, we can get the detailed stratigraphic framework of the different genetic units, in different scales. Within one sequence it is possible to predict the continuity, connectivity and extent of sand bodies, in which seismic reflectors are grouped into ranges that correspond to genetically related seismofacies and chronostratigraphically limited. The Santos Basin is one of the main Brazilian sedimentary basins for exploration and production of oil and gas, and has received increasing attention over the past few years given the recent large discoveries in the reservoirs of the pre-salt basin section, in addition to their traditional Cretaceous plays, even as current plays in the Lower Tertiary. It is situated in a unique geological context because of its adjacency to the Serra do Mar, a mountain range developed in the Tertiary in the context of a passive margin. The study of the Upper Cretaceous and Lower Tertiary sections of the basin becomes especially important for a better understanding of the events that occurred in the region adjacent to the Santos basin. In order to understand the stratigraphic framework of the depositional sequences and migration of the depocenters, a seismostratigraphic analysis was realized defining nine seismosequences using data from 2D seimic and wells. Isopach maps and the 3D sedimentary model were made, which clearly showed migration of the depocenter and depositional system for the nine seismosequences by direct influence of factors such as sediment yield, accommodation space, subsidence and eustatic level over the sedimentary record of the Upper Cretaceous and Lower Tertiary of the basin, especially the uplift of the Serra do Mar and organization of the drainage in the Cenozoic rift system