PALEOENVIRONMENTAL AND STRATIGRAPHIC SIGNIFICANCE OF MICROFOSSILS IN THE SCHWARZRAND SUBGROUP, NAMA GROUP.

• Grant number: 25/12943-4
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2025
• End date: August 31, 2026
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Principal Investigator: Juliana de Moraes Leme Basso
• Grantee: Ágatha Prada de Souza Camargo
• Host Institution: Instituto de Geociências (IGC). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 24/08023-4 - Shaping modern Earth, from Cryogenian extreme ice-ages to the Cambrian explosion, AP.TEM

Abstract

This project focuses on the study of microfossils from the Schwarzrand Subgroup (Nama Group) and aims primarily to advance knowledge about the paleoenvironment and biostratigraphic assemblages of microfossils associated with the Ediacaran-Cambrian transition within the Nama Group. The specific objectives of this work are: a- to describe and identify the microfossils present in the Schwarzrand Subgroup; b- to compare the microfossil assemblages of the Schwarzrand Subgroup with those from other Ediacaran units in Brazil, in order to establish paleoenvironmental conditions and assess their potential for biostratigraphic correlations. To achieve these goals, it is essential to characterize the morphology and composition of the microfossils, which will be carried out using microscopy techniques (optical and scanning electron microscopy) and spectrometry (Raman), as well as palynological methods for microfossil separation. This project is part of the International Continental Drilling Program (ICDP): "GRIND - Geological Research through Integrated Neoproterozoic Drilling", and the FAPESP Thematic Project (24/08023-4) "Defining the Modern Earth: from Cryogenian Snowball Earth to the Cambrian Explosion", whose goals involve several coordinated actions such as high-resolution, multi-proxy geochemical, geochronological, sedimentological, and paleontological studies of sedimentary successions obtained through core sampling. These studies span the Cryogenian, Ediacaran and Cambrian periods to assess the connections between local and global changes in seawater chemistry and the evolution of the biosphere. Regarding paleontology, the challenge is to understand the nature and triggers of life's evolution during the Neoproterozoic, which began with simple eukaryotic microorganisms and culminated in the emergence of oxygenated ecosystems and complex multicellular life during the Ediacaran-Cambrian interval. Thus, this study will contribute to a better understanding of the paleodiversity and paleoenvironment of the Schwarzrand Subgroup and support the establishment of biostratigraphic relationships and paleoenvironmental conditions that preceded and followed the Cambrian Explosion. (AU)