Exploration of morphological, geochemical and structural characteristics of microbialites to define new parameters of biogenicity

• Grant number: 22/00900-0
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Start date: November 01, 2022
• End date: October 29, 2023
• Field of knowledge: Physical Sciences and Mathematics - Geosciences
• Principal Investigator: Douglas Galante
• Grantee: Flávia Callefo
• Supervisor: Alexander Bjorling
• Host Institution: Centro Nacional de Pesquisa em Energia e Materiais (CNPEM). Ministério da Ciência, Tecnologia e Inovação (Brasil). Campinas , SP, Brazil
• Institution abroad: Lund University, Lund, Sweden
• Associated to the scholarship: 20/02537-5 - Exploring Nanopaleontology: new parameters of biogenicity and the study of biosignatures with synchrotron light, BP.PD

Abstract

Rocks from Precambrian ages can provide important information about the origin and evolution of life on Earth, as well as regarding the interaction between the biosphere and geosphere. The oldest records of life have often their biogenicity questioned. Materials like these have been explored using conventional techniques with spatial and spectral resolution limitations. Consequently, the presented biosignatures are often ambiguous. The possibility of applying micro and nanometric resolution techniques with multiple contrasts and high sensibility in 3rd and 4th generation synchrotron laboratories may provide solutions in problems related to biogenicity. Also, it can open a window for a new research field, the Nanopaleontology. The aim of this research is to explore this new field and propose new criteria of biogenicity of rocks. For this, a multi technique and multi scale approach will be applied using 4th generation synchrotron-based experimental stations with micro and nano-focusing available at Carnauba beamline (Sirius, Brazil) and NanoMAX (MAX IV, Sweden). Among the challenges to be addressed are the assessment of the biogenicity of rocks of until 3.7 billion years that may constitute the oldest evidence of life ever found on Earth; to evaluate the preservation of original morphologies, textures and composition along the geological time and after diagenetic processes; to investigate the compositional, morphological and structural features of the microbial samples with ptycho-tomography, micro and nano XRF and XRD; to evaluate better methods of preparing geological and paleontological samples for the nanoscale techniques. The intended results have the potential to make the involved beamlines references for studies in Nanopaleontology and Paleometry. (AU)