Please note that this session was withdrawn and is no longer available in the respective programme. This withdrawal might have been the result of a merge with another session.
BG5.2 | Precambrian Geobiology: Life and Environment
Precambrian Geobiology: Life and Environment
Convener: Jaganmoy Jodder | Co-conveners: Barbara Kremer, Fabian Zahnow, Eric Runge
The Precambrian witnessed profound evolutionary and environmental transformations that laid the foundation for life as we know it. Greenstone belts and cratonic cover sequences contain exceptional archives of this history, preserving sedimentary records that reveal conditions at the Earth’s surface, the chemistry of ancient oceans, and potential signatures of early microbial activity, including biomineralization. The Proterozoic fossil record, in particular, provides unique insights into the rise of eukaryotes and the emergence of complex life in the Ediacaran. These archives inform us on key themes such as the redox evolution of transitional oceans, the ecological balance of planktonic versus benthic microorganisms, the shift from Fe-rich to Fe-poor oceans, oxidative stress, and nutrient availability in subaqueous settings.
Recent advances in geochemical techniques underscore the value of interdisciplinary approaches that integrate field observations, experimental geobiology, and high-resolution isotopic analyses. This session welcomes contributions on Precambrian life and surface environments, with an emphasis on the earliest biosignature record. Topics of interest include the origin and diversification of early life, geobiological perspectives on cellular microstructures, oxygenation events, glaciations, biogeochemical cycling, climate, productivity, and the chemistry of ancient oceans.
We particularly encourage submissions employing cutting-edge methods such as high-resolution micro-CT imaging of macro- and microfossils, Raman spectroscopy, FIB-synchrotron analyses, nano-XRF, XANES, SIMS, nano-SIMS, phase propagation contrast tomography, TEM, and ATR-FTIR. We also welcome experimental and Precambrian-analog field studies aimed at biosignature and paleoenvironmental proxy development.