Análise estratigráfica da sequência siluriana da Bacia do Parnaíba, NE do Brasil

Abstract

This review presents a stratigraphic analysis of the Silurian Sequence of Parnaíba Basin and is related to the “Geology and Petroleum Systems of the Parnaíba Intracratonic Basin” Research Project, funded by Chevron Brasil and UFRN/PPGG/FUNPEC. The Parnaíba Basin is a paleozoic sineclisis which encompasses an area of approximately 600,000 km² and is located in the Northeastern Region of Brazil, distributed throughout the states of Maranhão, Piauí, Tocantins, Pará, Ceará e Bahia. The stratigraphic analysis implemented in this study was divided into two stages, referred to 1D and 2D analysis. In the 1D analysis well log data were used, such as gama ray and lithologic profiles, which provided the recognition of the genetic units and chronostratigraphic surfaces of sequence stratigraphy. On the other hand, the 2D analysis was based on the seismic interpretation, which along with the 1D analysis allowed the delimitation of the stratigraphic surfaces and the understanding of the bidimensional behavior of the genetic units identified .At this stage, a stratigraphic section with NW-SE direction, approximately, was created as well, providing a better understanding about the sedimentary evolution of the studied section.