Paired sulfur isotopes of the Tagatiya Guazú Formation (PY) and Murciélago Group (BO), southwestern Gondwana

• Grant number: 24/05052-3
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: August 01, 2025
• End date: July 31, 2026
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Principal Investigator: Lucas Verissimo Warren
• Grantee: Gabriel Correa Antunes
• Supervisor: Shuhai Xiao
• Host Institution: Instituto de Geociências e Ciências Exatas (IGCE). Universidade Estadual Paulista (UNESP). Campus de Rio Claro. Rio Claro , SP, Brazil
• Institution abroad: Virginia Polytechnic Institute and State University, United States
• Associated to the scholarship: 22/09290-0 - Paleoenvironmental reconstruction of the Ediacaran-Cambrian transition in the Southwestern part of Gondwana, BP.DR

Abstract

The Ediacaran-Cambrian transition, marked by the emergence of biocalcifying organisms and complex trace fossils, is a crucial period in geological history. Proposed causes for the appearance of major bilaterian clades involve environmental, evolutionary, and ecological factors, such as oxygenation, nutrient availability, and seawater composition changes, with major hypotheses being studied mainly in the Nama Group (Namibia) and Dengying Formation (China). With our main project, we propose a similar approach for the Tagatiya Guazú Formation (Paraguay) and the Murciélago Group (Bolivia), through sedimentological, paleontological, and geochemical data analysis, including REY, RSEs, bioproductivity tracers, TOC, and carbon, sulfur and oxygen isotopes. Considering the above scenario, this research internship project seeks to advance the paleoenvironmental characterization of these units by the acquisition of paired sulfur isotopes (´34SCAS and ´34Spyr). Sulfur isotopic signatures in the Ediacaran Period are quite heterogeneous due to low sulfate concentrations and frequent distillation events. Understanding this heterogeneity is crucial for evaluating possible oxygenation events, as sulfate and sulfide inputs and outputs can influence atmospheric oxygen concentrations, playing a pivotal role in biogeochemical and redox paleoenvironmental reconstitutions. The internship will be developed at the Virginia Tech University (USA) and supervised by Prof. Dr. Shuhai Xiao, one of the greatest experts in the field, possessing a huge earning potential for the student's career and ultimately helping to develop these techniques in the home institution.