Grinding through the Ediacaran-Cambrian Transition
- 1School of Earth & Environmental Sciences, University of St Andrews, Fife KY16 9AL, UK
- 2Department of Earth & Planetary Sciences, John Hopkins University, Baltimore, MD 21218
- 3Goethe-Universität Frankfurt am Main, Altenhöferallee 1, 60438 Frankfurt am Main, Germany
- 4MARUM – Center for Marine Environmental Sciences and Faculty of Geosciences, University of Bremen, Germany
- 5Department of Earth Sciences, University of California Santa Barbara, CA 93106, USA
- 6Regional Geoscience Division, Geological Survey of Namibia, Windhoek, Namibia
- 7Department of Geosciences, Smith College, Northampton, MA 01063, USA
- 8Instituto de Astronomia, Geofísica e Ciências Atmosféricas, Universidade de São Paulo, 05508-900 São Paulo, Brazil
- 9Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China
The Neoproterozoic Era (1000 - 541 Ma) is one of the most dramatic in Earth history: metazoans evolved, the supercontinent Rodinia formed and broke apart, the global carbon cycle underwent high-amplitude fluctuations, oxygen concentrations rose and climate experienced at least two episodes of worldwide glaciation. However, the discontinuous and fragmented nature of outcrop-based studies has hindered developing quantitative models of Earth system functioning during that Era. The Geological Research through Integrated Neoproterozoic Drilling (GRIND) project begins to rectify this scientific shortcoming by obtaining 13 cores through the archetype successions that record this environmental and biogeochemical change.
The specific targets are the Ediacaran-Cambrian transition (ECT; c. 560-530 Ma) in south Namibia (Nama Group), strata of west Brazil (Corumbá Group), and South China (Doushantuo, Dengying and equivalent formations). Drilling in Namibia and Brazil is complete, and drilling in China will commence in 2023. The work aims to 1) construct a highly resolved temporal framework that will lead to the development of age models for the ECT; 2) refine the patterns of biotic evolution of organic-walled and mineralised microfossils, metazoans and trace fossils, and identify the links between and test hypotheses about biological evolution and environmental change, and 3) using fresh, unweathered samples, determine the palaeoenvironmental and biogeochemical conditions that led to the rise of oxygen and distinguish cause-and-effect relationships and basin-specific versus global-scale secular trends in geochemical and stable isotope patterns.
We present sedimentological data from the characterised split cores from Namibia and Brazil, which are permanently archived at an in-country repository as well as the Federal Institute for Geosciences and Natural Resources in Germany. All cores will be available for future research, education and national capacity building activities and mark the first step towards creating an on-shore core archive that will match in stature that of the IODP.
How to cite: Rose, C., Prave, T., Baillie, I., Cantine, M., Kasemann, S., Macdonald, F., Mesli, M., Nduutepo, A., Pruss, S., Trindade, R., and Zhu, M.: Grinding through the Ediacaran-Cambrian Transition, EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-9523, https://doi.org/10.5194/egusphere-egu23-9523, 2023.
