Biostratigraphy of Miocene-Pliocene sequences of the Macuspana basin, southeastern Gulf of Mexico

Abstract

ABSTRACT

This paper presents an integrated analysis of data from calcareous nannofossils, foraminifera and geophysical logs from two exploratory wells in the Macuspana basin, southeastern Gulf of Mexico. This combination permits to propose a sequence stratigraphy framework for the studied wells. Biostratigraphic resolution and reliability increase with the integration of results from both fossil groups. On well A, the following species are used: Helicosphaera kamptneri, Reticulofenestra pseudoumbilica, Minylitha convallis, Discoaster hamatus, Globorotalia obesa and Globorotalia mayeri. On well B, the useful species are: Calcidiscus macintyrei, Reticulofenestra pseudoumbilica, Discoaster quinqueramus and Globorotalia mayeri. In well A, three stratigraphic sequence candidates are recognizable, and they are correlatable with the third order eustatic cycles TB-2.6, TB-3.1 and TB-3.5?. In well B, five stratigraphic sequence candidates are recognized, which are correlatable with the third order eustatic cycles TB-2.6, TB-3.1, TB-3.2, TB-3.3 and TB-3.6?. Results indicate that the studied sections were deposited from middle Miocene to Pleistocene. The biostratigraphic results, combined with sequence stratigraphy, will help to propose a sequence stratigraphy model.