Tectono-Stratigraphic Evolution of the Brazilian South-Eastern Margin - The ATLANTIS Project and its Impact on Pre-Salt Research

Abstract

Summary The discovery of giant hydrocarbon accumulations in the pre-salt play, offshore south-eastern Brazil led to large-scale data acquisition, with dense 2D seismic grid and broad 3D seismic data coverage, with more data being acquired currently. More than 100 exploratory wells had penetrated the pre-salt, with most of the acquired data already in the public domain, including logs, cores, and well reports. This rich geologic dataset is being interpreted in the ATLANTIS Project to build a regional and integrated paleogeographic reconstruction of the Brazilian Southeastern Margin. The goal is to de-risk play-elements presence and quality in the pre-salt section, as well as to build predictive models for CO2 distribution in the region. This project also has the potential to evaluate the remaining potential for economic hydrocarbon accumulations in this important play. Preliminary results indicate that the main, regional controls on accommodation creation and the petroleum systems elements distribution from continental rifting to early drift phases in the region are: inherited Neoproterozoic structural lineaments and Mesozoic continental weaknesses zones, subaerial volcanism pre- and post-continental breakup controlling the development of early seaways and sub-basins, and transcurrent faults zones and consequent transtension and transpression.