Notebook resting on an Ice Age or the transition from the Tonian Skillogallee and Myrtle Springs Formations to the overlying Cryogenian Sturt Formation (Sturt Glaciation, marked by the notebook) in the Willouran Ranges, Adnyamathanha Country, South Australia. Image: Alan Collins ARC Future Fellow Dr Adriana Dutkiewicz from the EarthByte Group and colleagues have used NCRIS … Read more…
Reposted from Earth Logs by Steve Drury The Cryogenian Period that lasted from 860 to 635 million years ago is aptly named, for it encompassed two maybe three episodes of glaciation. Each left a mark on every modern continent and extended from the poles to the Equator. In some way, this series of long, frigid … Read more…
8 February 2024, University of Sydney Media release Historically low volcanic emissions and weathering events seem likely cause Dr Adriana Dutkiewicz was inspired during a field trip to the Flinders Ranges to find out how volcanic activity turned our blue dot to an ice covered planet. Together with Professor Dietmar Muller and the EarthByte group, … Read more…
The termination of Neoproterozoic “Snowball Earth” glaciations is marked globally by laterally extensive neritic cap carbonates directly overlying glacial diamictites. The formation of these unique deposits on deglaciation calls for anomalously high CaCO3 saturation. A popular mechanism to account for the source of requisite ocean alkalinity is the shallow-ridge hypothesis, in which initial spreading ridges … Read more…
The Sturtian ‘Snowball Earth’ glaciation (~717–661 Ma) is regarded as the most extreme interval of icehouse climate in Earth’s history. The exact trigger and sustention mechanisms for this long-lived global glaciation remain obscure. The most widely debated causes are silicate weathering of the ~718 Ma Franklin LIP, and changes in the length and degassing of … Read more…
Understanding the long-term evolution of Earth’s plate-mantle system is reliant on absolute plate motion models in a mantle reference frame, but such models are both difficult to construct and controversial. We present a tectonic rules-based optimisation approach to construct a plate motion model in a mantle reference frame covering the last billion years and use … Read more…
Recent progress in plate tectonic reconstructions has seen models move beyond the classical idea of continental drift by attempting to reconstruct the full evolving configuration of tectonic plates and plate boundaries. A particular problem for the Neoproterozoic and Cambrian is that many existing interpretations of geological and palaeomagnetic data have remained disconnected from younger, better-constrained … Read more…