South Australian U-Pb Zircon (CA-ID-TIMS) Age Supports Globally Synchronous Sturtian Deglaciation
A central prediction of the Snowball Earth hypothesis is that glacial onset should be synchronous at low latitudes, and its termination should be rapid and synchronous globally. High precision U/Pb zircon ages provide supporting evidence for the synchronous onset (within error) of the Sturtian glaciation (ca. 716 Ma) on multiple continents. Successful application of Re-Os techniques on organic rich shales and carbonates allow for the possibility of a globally synchronous Sturtian deglaciation (ca. 660 Ma), but the sparse isotopic age constraints leave this open to debate. Here we report the first high precision U-Pb zircon age of 663.03 ± 0.11 Ma (2σ) for the end Sturtian recorded in the Wilyerpa Formation of South Australia. This age supports previously published ages and is permissive with a globally synchronous deglaciation. In conjunction with the timing of glacial onset, this age reinforces the ca. 58 Myr duration of the Sturtian Snowball.
Isakson, Vincent and Schmitz, Mark D. (2018). "South Australian U-Pb Zircon (CA-ID-TIMS) Age Supports Globally Synchronous Sturtian Deglaciation". Precambrian Research, 315, 257-263. http://dx.doi.org/10.1016/j.precamres.2018.07.007