"Caracterização Sedimentológica Preliminar da Área de Influência do Porto de Vila do Conde - Barcarena/PA"

Abstract

The Vila do Conde Terminal is located on the right bank of the Pará River, in the Municipality of Barcarena/PA. It was inaugurated in the 1980's to provide support to the Albras-Alunorte complex. In this context, there is an intense flow of ships and rafts in the waters of the Pará River, configuring a high risk character in case of an eventual accident involving spillage of hydrocarbon derivatives. Through the PIATAM-mar Project, Petrobrás has been seeking to understand the structure and dynamics of the Amazonian coastal environments. Thus, the present work is part of the goals established by the project that aimed at the elaboration of a preliminary chart of the faciologic distribution of the bottom sediments of the Pará River (scale 1: 10,000), more precisely in the area of influence of the Port of Vila do Conde. The bathymetric survey kindly provided by the Administração das Hidrovias da Amazônia Oriental (AHIMOR) was used to plan the sampling grid. A total of 254 sediment samples were collected and submitted to classical sedimentological treatments (washing, sieving, and particle size analysis). Larsonneur's classification was used to classify the sediments, a chart was generated with 65% of the collected samples. Preliminary results indicate that the predominance of the bottom sediments in the studied area is medium lithoclastic sand and lithoclastic sand with granules. Locally, rocky outcrops (Laterite - Barrier Formation) were recorded in the sectors closest to the shore. Further north, in the vicinity of Ponta do Miritizal, outcropping of the clayey facies of the Barreiras Formation is remarkable, as well as next to Ponta da Espera. Itupanema beach showed a heterogeneous distribution of sediments, varying from mud more to the south to lithoclastic sand with granules to the north. Medium lithoclastic and lithoclastic sand with granules were predominant in the main channel of the harbor. With the processing of all samples we will have a more accurate sediment distribution chart.