Project Details
Projekt
Decrypting tidal- and Milankovitch-driven sedimentary rhythms in nearshore strata of the Archean Moodies Group, South Africa
Applicants
Dr. Marcello Gugliotta; Professor Dr. Christoph Heubeck; Professor David De Vleeschouwer, Ph.D.
Subject Area
Geology
Term
since 2023
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 517378408
Decrypting sedimentary rhythms in deep-time Precambrian sedimentary archives could mark a quantum leap in the reconstruction of ancient sedimentary environments under boundary conditions dramatically different from today’s. Theoretically, Precambrian sedimentary rhythms even hold the potential to quantitatively constrain aspects of the history of the solar system, including Earth-Moon interaction. In practice, however, such reconstructions are hampered by poor stratigraphic control and a very limited number of suitable sedimentary archives. The new drill cores of the ICDP BASE Project in the 3.22 Ga Moodies Group of the Barberton Greenstone Belt (South Africa) are, however, well-suited to reinvigorate long-standing questions regarding the role of astronomical and tidal forcing in the Precambrian. This is because these cores provide a continuous sedimentary record, unaffected by differential weathering and marked by repeating sedimentary patterns at a wide range of depth scales, through a large part of Moodies Group stratigraphic thickness (up to 3.7 km). Hence, the overall objective of this proposal is to evaluate the following hypothesis: The imprint of tidal and Milankovitch astronomical forcing can be detected and differentiated from autocyclic processes in some of the oldest shallow-water sedimentary rocks on Earth. The anticipated results have implications for our understanding of Archean paleo-environments, their sensitivity to different forcing mechanisms, and for constraining the behaviour of our solar system more than 3 billion years ago. The tidal aspects of this project (conducted in Bremen) will explicitly challenge the paradigm that the Archean was a tidal world. In doing so, this project is closely aligned with new insights from tidal sedimentology, and addresses the open question of the role of tides in the Earth’s deep time of the Earth. The astronomical Milankovitch aspects of this project (conducted in Münster) will evaluate rhythmical sedimentary patterns, their frequency ratios and amplitude modulation patterns on meter and decameter-scales to differentiate allocyclic from autocyclic imprints. The combined assessment of sedimentary cyclicity across time- and depth-scales has never been attempted for Archean systems and could entail a major advance in understanding Archean paleo-environments, Earth-Moon dynamics, and possible relationships between stronger or weaker tides under certain astronomical configuration.
DFG Programme
Infrastructure Priority Programmes
International Connection
United Kingdom
Co-Investigator
Privatdozent Dr. Georg Feulner
Cooperation Partner
Professor Dr. Mattias Green
