Grant: Alliance Grants

The late Neoproterozoic Era, between ca. 745 and 539 million years ago, marks a crucial interval in Earth's history. During this time period, Earth experienced multiple glaciations, two of which were global in extent, significantly increased atmospheric oxygen levels, and the rise and diversification of complex life, which set in motion the Cambrian radiation of animals. Despite the importance of these critical events, little is known about the role of cyclic oscillations in Earth's orbit and inclination (Milankovitch cycles) on Neoproterozoic climate and environments. Milankovitch cycles are known to have modulated Phanerozoic climate, including the advance and retreat of Pleistocene ice ages, oxygen levels in the oceans and the distribution and evolution of flora and fauna, including humans. The objective of this International Alliance project is to test whether orbital forcing played a role in triggering major climatic and biospheric change during the Neoproterozoic, with emphases on the time intervals spanning the two global glaciations and the appearance and diversification and eventual disappearance of the Ediacaran biota at the close of the Precambrian (~539 million years ago). This project will foster a multi-disciplinary team of leading researchers in their fields who together will integrate cutting edge cyclostratigraphic, biostratigraphic, chemostratigraphic and sequence stratigraphic techniques with high-precision single zircon U-Pb geochronology, isotope geochemistry and Bayesian age depth modelling. The results will provide novel insights into the Earth system during this great transition in its history. This effort will place Canada and its researchers firmly at the forefront of understanding links between the solar system, Earth's surface environment, climate and complex life.