Predicting deglacial stratigraphy following Snowball Earth with 3D forward modelling
- 1University of Hong Kong, Pokfulam, Hong Kong (adam.nordsvan@gmail.com)
- 2Chinese Academy of Sciences, Beijing, China
- 3University of Victoria, Victoria, Canada
- 4University of Potsdam, Potsdam-Golm, Germany
Rapid eustatic rise during deglaciations should cause sedimentary condensation and depositional hiatuses on marine shelves. Determining the duration of these hiatuses is challenging, especially in sequences that cannot be reliably dated. Recently, it was suggested that a global prolonged hiatus could have ensued following the Neoproterozoic Snowball Earth events. However, the duration and stratigraphic characteristics of these events are uncertain. Here, we utilize 3D stratigraphic forward modelling software DionisosFlow to 1) estimate its duration following a Snowball Earth when considering 800 m glacioeustatic rise over 40 kyr, and 2) explain the stratigraphic fingerprint of such an event. We tested several margin configurations and different sediment flux scenarios; our findings indicate that the duration of the hiatus, as predicted, will increase with accommodation, and decrease with sediment supply. Simulating an average (modern) glaciated margin with an average sediment flux results in prolonged sediment starvation on the outer shelf, lasting over 6 Myr. More complex models show how topography, sediment type, and sediment volume during and after the deglaciation affect the stratigraphic record. We compare the predicted model outputs with observed Snowball Earth stratigraphy from the Kimbereley region of NW Australia to reconstruct the paleoenvironmental conditions. This work demonstrates how 3D stratigraphic modeling can help clarify deglacial stratigraphy.
How to cite: Nordsvan, A., Mitchell, R., Bauer, K., Colleps, C., and McKenzie, R.: Predicting deglacial stratigraphy following Snowball Earth with 3D forward modelling, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12967, https://doi.org/10.5194/egusphere-egu24-12967, 2024.