The origin of carbon isotope vital effects in coccolith calcite
Calcite microfossils are widely used to study climate and oceanography in Earth's geological past. Coccoliths, readily preserved calcite plates produced by a group of single-celled surface-ocean dwelling algae called coccolithophores, have formed a significant fraction of marine sediments since...
Saved in:
Published in | Nature communications Vol. 8; no. 1; p. 14511 |
---|---|
Main Authors | , , , |
Format | Journal Article |
Language | English |
Published |
England
Nature Publishing Group
06.03.2017
Nature Portfolio |
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | Calcite microfossils are widely used to study climate and oceanography in Earth's geological past. Coccoliths, readily preserved calcite plates produced by a group of single-celled surface-ocean dwelling algae called coccolithophores, have formed a significant fraction of marine sediments since the Late Triassic. However, unlike the shells of foraminifera, their zooplankton counterparts, coccoliths remain underused in palaeo-reconstructions. Precipitated in an intracellular chemical and isotopic microenvironment, coccolith calcite exhibits large and enigmatic departures from the isotopic composition of abiogenic calcite, known as vital effects. Here we show that the calcification to carbon fixation ratio determines whether coccolith calcite is isotopically heavier or lighter than abiogenic calcite, and that the size of the deviation is determined by the degree of carbon utilization. We discuss the theoretical potential for, and current limitations of, coccolith-based CO
paleobarometry, that may eventually facilitate use of the ubiquitous and geologically extensive sedimentary archive. |
---|---|
Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 PMCID: PMC5343501 |
ISSN: | 2041-1723 2041-1723 |
DOI: | 10.1038/ncomms14511 |