Isotopic evidence for variations in the marine calcium cycle over the Cenozoic.
Significant variations in the isotopic composition of marine calcium have occurred over the last 80 million years. These variations reflect deviations in the balance between inputs of calcium to the ocean from weathering and outputs due to carbonate sedimentation, processes that are important in controlling the concentration of carbon dioxide in the atmosphere and, hence, global climate. The calcium isotopic ratio of paleo-seawater is an indicator of past changes in atmospheric carbon dioxide when coupled with determinations of paleo-pH.
De La Rocha
C L
CL
Berkeley Center for Isotope Geochemistry, Department of Geology and Geophysics, University of California, Berkeley, CA 94720-4767, USA.
DePaolo
D J
DJ
D000818:Animals; D001272:Atmosphere; D002118:Calcium / Q000378:metabolism*; D002127:Calcium Isotopes; D002245:Carbon Dioxide; D002254:Carbonates / Q000378:metabolism; D056890:Eukaryota / Q000378:metabolism*; D019015:Geologic Sediments; D006863:Hydrogen-Ion Concentration; D008386:Marine Biology; D010933:Plankton / Q000378:metabolism*; D012623:Seawater
D002127:Calcium Isotopes; D002254:Carbonates; D002245:Carbon Dioxide; D002118:Calcium