The aim of this project is to develop a robust understanding of the nature of earth surface systems during extreme Neoproterozoic glaciations in NE Svalbard and to generate key data on the Cryogenian succession in the depositional basin to facilitate the choice of a global stratotype.
The Neoproterozoic Era (1000-542 Ma) is famous for its ice ages, especially within the eponymous Cryogenian period (800-630 Ma). The Cryogenian glaciations appear to have been prolonged disturbances of the Earth System that were more severe than any subsequent perturbation (Fairchild & Kennedy, 2007). They have left a record of glacigenic sediments on all continents. Of these, Svalbard glacigenic sediments are among the best preserved in the world.
This work follows the recent publication of startling new evidence (Bao et al, 2009) for a highly modified palaeo-atmosphere in the Cryogenian, consistent with a near-global cover of snow and ice that would have permitted carbon dioxide to accumulate in the atmosphere to high levels over millions of years as a result of deep earth outgassing (Hoffman & Schrag, 2002). This work was based on glacial lake carbonates collected during brief fieldwork in the early 1980s. These now-exhausted samples proved scientifically important because;
- They displayed high quality preservation of both environmental and atmospheric signal, including arguably primary oxygen isotope signatures
- They are unique: in contrast to the much-studied marine deposits, they are by far the most extensive evidence of chemical precipitation in terrestrial conditions during a Neoproterozoic glaciation
This project represents the start of a new phase of work on these well-exposed yet under-researched deposits of Neoproterozoic rocks in North East Svalbard to provide robust tests for the nature of the climate, environment, atmosphere and palaeogeography, using insights from state-of-the-art sedimentary and geochemical models of proposed modern Antarctic analogues of the glacial lakes (Green & Lyons, 2009; Hall et al, 2006; Hendy et al, 2000).