Earth and Planetary Science
EPS Atmosphere, Oceans, and Climate

The arc of the Snowball: U-Pb dates constrain the Islay anomaly and the initiation of the Sturtian glaciation

Thursday, July 19, 2018

Scott MacLennan, Yuem Park, Nicholas Swanson-Hysell, Adam Maloof, Blair Schoene, Mulubrhan Gebreslassie, Eliel Antilla, Tadele Tesema, Mulugeta Alene, Bereket Haileab

 

Geology (2018) 46 (6): 539-542.    https://doi.org/10.1130/G40171.1

 

 

In order to understand the onset of Snowball Earth events, precise geochronology and chemostratigraphy are needed on complete sections leading into the glaciations. While deposits associated with the Neoproterozoic Sturtian glaciation have been found on nearly every continent, time-calibrated stratigraphic sections that record paleoenvironmental conditions leading into the glaciation are exceedingly rare.  Instead, the transition to glaciation is normally expressed as erosive contacts with overlying diamictites, and the best existing geochronological constraints come from volcanic successions with little paleoenvironmental information. We report new stratigraphic and geochronological data from the upper Tambien Group in northern Ethiopia,