Fossil Echinoderms As Monitor of the Mg/Ca Ratio of Phanerozoic Oceans
Abstract
Opinion has long been divided as to whether the Mg/Ca ratio of seawater remained constant during the Phanerozoic or underwent substantial secular change. Existing empirical evidence for the Mg/Ca of ancient seawater provides a poorly resolved and often controversial signal. Echinoderm fossils that have retained their bulk original chemistry, despite micrometer-scale changes, preserve a record of seawater Mg/Ca and confirm that major changes in Mg/Ca occurred during the Phanerozoic. Echinoderms from the Cambrian and from the Carboniferous to the Triassic indicate a seawater Mg/Ca of ∼3.3, whereas echinoderms from the Jurassic to the Cretaceous indicate a Mg/Ca of ∼1.4. The present seawater Mg/Ca is ∼5.
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References 32 · Cited by 249
- Authors
- Dickson, J. A. D.
- Affiliations
- University of Cambridge (GB)
- Corresponding author
- Dickson, J. A. D.
- ORCID
- Dickson, J. A. D.
- Venue
- Science
- Published
- 2002-11-08
- Volume
- 298
- Issue
- 5596
- Pages
- 1222-1224
- ISSN
- 0036-8075 (ISSN-L)
- 1095-9203
- OpenAlex
- W1976591828
- Cited by
- 249
- References
- 32
- Citations by year
- 2026: 2 · 2025: 4 · 2024: 11 · 2023: 16 · 2022: 13 · 2021: 9 · 2020: 13 · 2019: 11 · 2018: 8 · 2017: 10 · 2016: 8 · 2015: 6 · 2014: 6 · 2013: 16 · 2012: 7
- FWCI
- 9.57
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Science (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Physical Sciences › Earth and Planetary Sciences › Paleontology › Paleontology and Stratigraphy of Fossils
- Physical Sciences › Earth and Planetary Sciences › Geochemistry and Petrology › Geochemistry and Elemental Analysis
- Physical Sciences › Earth and Planetary Sciences › Atmospheric Science › Geology and Paleoclimatology Research
- Keywords
- Mg/Ca ratio, seawater chemistry, fossil echinoderms, paleoceanography, Cambrian
- MeSH terms
- Animals, Calcium, Calcium Carbonate, Echinodermata, Fossils, Geology, Magnesium, Sea Urchins, Seawater, Temperature, Time, Geological Phenomena
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