Micropaleontology as a Tool for Paleoenvironmental and Biostratigraphic Reconstructions in Sedimentary Basins of Northeastern Brazil

• Grant number: 25/23784-4
• Support Opportunities: Scholarships in Brazil - Program to Stimulate Scientific Vocations
• Start date: January 12, 2026
• End date: March 03, 2026
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Principal Investigator: Enelise Katia Piovesan
• Grantee: Lorena Ávila da Gama Silva
• Host Institution: Centro de Tecnologia e Geociências (CTG). Universidade Federal de Pernambuco (UFPE). Recife , SP, Brazil

Abstract

Micropaleontology, as a specialized branch of Paleontology, is dedicated to the study of microfossils, which are diminute organisms or fragments of larger organisms that lived in the geological past. These fossils can be classified according to their chemical composition into three major groups: carbonate microfossils, such as ostracods, foraminifera, and calcareous nannofossils; siliceous microfossils, such as radiolarians and diatoms; and organic microfossils, including pollen, spores, and dinoflagellate cysts. Due to their wide geographic distribution, abundance, and diversity, microfossils have remarkable applicability in taxonomic, biostratigraphic, paleoecological, and paleogeographic studies, often surpassing macrofossils in resolution and utility. Their systematic classification is based on morphological, structural, and ornamental features specific to each group, as well as ecological preferences and environmental distribution patterns. In this context, foraminifera, ostracods, and calcareous nannofossils stand out as excellent index fossils, essential for chronostratigraphic correlations on both regional and global scales. In addition to their temporal significance, microfossils are extensively used in paleoenvironmental reconstructions, since the relationships between organisms and the environments in which they lived allow inferences about physicochemical conditions such as depth, salinity, organic productivity, oxygenation, and climate. At the Applied Micropaleontology Laboratory (LMA/UFPE), part of the Petroleum and Energy Research Institute (i-LITPEG), micropaleontological analyses follow standardized protocols adapted to lithological characteristics and the type of microfossil under investigation. Samples undergo weighing, maceration, and immersion in water for approximately 24 hours, with hydrogen peroxide (H¿O¿) applied in specific cases. They are then washed through granulometric sieves ranging from 500 to 63 µm, followed by oven drying at 60 ºC. The dried residues are stored in properly labeled containers and subsequently examined under stereomicroscopes (Zeiss Stemi 305/AxioZoom V12) and scanning electron microscopy (SEM), enabling detailed analyses of morphological features that support taxonomic classification.Thus, Micropaleontology is consolidated as an essential tool in geoscientific research applied to the sedimentary basins of Northeastern Brazil. The combination of its high biostratigraphic resolution, together with its potential for paleoenvironmental reconstruction and capacity for long-distance correlations, gives microfossils a central role in the development of evolutionary, stratigraphic, and paleogeographic models, as well as in the direct exploration of natural resources.