Towards an integrated stratigraphic and carbon-isotopic record for the Neoproterozoic

Abstract

Abstract provided by author:

Assuming a link between the global carbon cycle and climate, these clues impose critical constraints on what mechanisms may have been responsible for the anomaly and the initiation of global cooling. At the same time, this pre-glacial d13C anomaly can be used for correlation. Presumably the anomaly shows up in successions around the word, including northeastern Svalbard and northern Norway

Correlations between Namibia, Svalbard, and Norway (all of which host a pair of diamictites) based on the anomaly, as well as cap carbonate characteristics, have important implications. First, both diamictites in Svalbard are Marinoan in age; analogous Marinoan diamictite pairs are found in several other successions. Second, the upper diamictite in Norway must be post-Marinoan, indicating that there were three Neoproterozoic ice ages. This late (Varanger) glaciation appears to be related to the most extreme Neoproterozoic negative d13C anomaly, but is not overlain by a cap carbonate. Third, the Svalbard and Namibia records can be combined to produce a high-resolution composite d13C record that spans over half of the Neoproterozoic