Can zircon constrain glacial processes?

Abstract

Zircon grains provide insights into crustal production and loss via erosion throughout Earth’s history. We apply multi-dimensional scaling of U-Pb detrital zircon compilations and demonstrate that these depositional patterns were primarily influenced by the rifting of Rodinia and the assembly of Gondwana supercontinents. We identify two-step changes in a zircon dataset spanning the tenure of these continental aggregations, defined by an increase in δ18O values related to the Sturtian and Marinoan ‘Snowball Earth’ glaciations. Correlation between magmatic and detrital zircon Hf and O isotopes implies a flux of old (radiogenically enriched) sediment multiple times during the Tonian and Cryogenian. εHf/δ18O signature at 690 Ma indicates a major flux of old sediment into magmatic systems, which we interpret as due to deep glacial erosion of continental crust during Cryogenian glaciations, corroborating prior studies. This work provides a new quantitative perspective on orogenic and climatic processes that supply sediments to magmatic systems.