Journal article

Marine cements reveal the structure of an anoxic, ferruginous Neoproterozoic ocean

Ashleigh VS Hood, Malcolm W Wallace

Journal of the Geological Society | Geological Society | Published : 2014

Abstract

Neoproterozoic oceans provided the setting for the rise of animals, yet little is known of their chemical composition. Marine carbonates from the Cryogenian Oodnaminta Reef Complex, South Australia, reveal the chemical structure of a Neoproterozoic ocean. Pseudo-depth profiles from shallow- to deep-water reef facies have been constructed from geochemical and sedimentological analysis of marine cements. Evidence suggests that under peritidal oxic/anoxic chemocline, the water column was largely anoxic, strongly ferruginous and had a chemistry profoundly different from modern seawater. These geochemical data suggest early Archean-like conditions for this Late Cryogenian ocean, posing problems f..

View full abstract

Grants

Awarded by Australian Research Council


Funding Acknowledgements

We would like to thank two anonymous reviewers for their constructive comments, which helped improve this paper. The authors acknowledge the Australian Research Council Discovery Project 130102240 for financial assistance with this research. We would like to thank D. and M. Sprigg for their long-term logistic assistance with fieldwork at Arkaroola.