Facies control on carbonate δ13C on the Great Bahama Bank

TitleFacies control on carbonate δ13C on the Great Bahama Bank
Publication TypeJournal Article
Year of Publication2021
AuthorsGeyman EC, Maloof AC
JournalGeology
Volume49
Issue9
Pagination1049–1054
Date Published05/17/2021
ISBN Number0091-7613
Other Numbers75Maloof
Abstract

The carbon isotopic (δ13C) composition of shallow-water carbonates often is interpreted to reflect the δ13C of the global ocean and is used as a proxy for changes in the global carbon cycle. However, local platform processes, in addition to meteoric and marine diagenesis, may decouple carbonate δ13C from that of the global ocean. We present new δ13C measurements of benthic foraminifera, solitary corals, calcifying green algae, ooids, coated grains, and lime mud from the modern Great Bahama Bank. We find that vital effects, cross-shelf seawater chemistry gradients, and meteoric diagenesis produce carbonate with δ13C variability rivaling that of the past two billion years of Earth history. Leveraging Walther’s Law, we illustrate how these local δ13C signals can find their way into the stratigraphic record of bulk carbonate.

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URLhttps://doi.org/10.1130/G48862.1
DOI10.1130/G48862.1
Short TitleGeology