Stars, Cells, and God | Snowball Events Timed for Advanced Life | News of the Day

Join Hugh Ross in this breaking News of the Day episode of Stars, Cells, and God. Hugh describes the first-ever accurate dating of the beginning and ending of the Sturtian snowball event, which covered 80%+ of Earth’s surface with thick ice and how this precise timing made possible advanced life. Previous attempts to date the Sturtian snowball event were based on 5 or less detrital zircons. Geologists recovered more than 2,000 detrital zircons from the Port Askaig Formation in Scotland, where advancing and retreating glaciers had not eroded away the historical record of the Sturtian and in the words of the lead author, “by some miracle the transition can be seen.” Uranium-lead isotope measurements of the zircons yielded radiometric dates for when the sedimentary layers in the Port Askaig Formation transitioned from warm tropical to cold glacial conditions and from cold glacial to warm tropical conditions. The uranium-lead derived ages showed that the Sturtian snowball event lasted from 720 to 663 million years ago.. The Sturtian dramatically reduced carbon dioxide and dramatically increased oxygen in Earth’s atmosphere. If the Sturtian had occurred any earlier, the Sun would have been too dim to prevent Earth from being permanently covered with ice. On the other hand, if the Sturtian had occurred any later, the brighter Sun would have shortened the duration and limited the ice coverage, resulting in too little oxygen and too much carbon dioxide in Earth atmosphere, ruling out the possibility of advanced life. Links and Resources: Glacially Influenced Provenance and Sturtian Affinity Revealed by Detrital Zircon U–Pb Ages from Sandstones in the Port Askaig Formation, Dalradian Supergroup Hugh Ross, Designed to the Core (Covina, CA: RTB Press, 2022): 218–220.