Geochemical tracers of biomineralisation processes

Book section

Biominerals play a central role in Earth's past, present and future climate, but there are major gaps in our understanding of how they form. In this chapter, we consider how the geochemistry of calcium carbonate biominerals may be used to interrogate the mechanisms that produce them. We review the range of biological, and mineralogical processes that are thought to be involved in biomineralization, set out a conceptual framework for how these processes combine to determine the geochemistry of the biomineral structure, and consider characteristic geochemical patterns that can be diagnostic of specific biomineralization mechanisms. We then explore four case studies with relevance to different aspects of biomineralization, delving into the fine detail of the mineralogical and biological controls on biomineral geochemistry. We begin from the inorganic perspective, with a review of the geochemistry of ‘classical’ crystal growth, then move towards biomineral systems with a consideration of the formation and transformation of amorphous calcium carbonate phases. We then consider the geochemistry of corals and foraminifera, which have some degree of connection to external seawater during calcification. Finally, we contrast this to the coccolithophores, which calcify in an environment that is completely isolated from seawater. Together, this offers an overview of the controls on biomineral geochemistry, and the key knowledge gaps in this field.

Authors: Branson, O; Chauhan, N; Evans, D; Foster, GL; Rickaby, REM

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Elsevier
• Host title: Treatise on Geochemistry (Third Edition)
• Pages: 177-235
• Publication date: 2024-09-20
• Acceptance date: 2024-05-19
• Edition: 3
• DOI: 10.1016/B978-0-323-99762-1.00128-5
• EISBN: 9780323997638
• ISBN: 9780323997621
• Language: English
• Keywords: biomineral; trace element; isotope; biomineralisation; calcification; precipitation rate; partitioning; fractionation; distribution; ion transport; amorphous calcium carbonate; vacuolisation; Ca channel; Rayleigh fractionation