Abstract

Fluid inclusion data suggest that the composition of major elements in seawater changes slowly over geological time scales. This view contrasts with high-resolution isotope data that imply more rapid fluctuations of seawater chemistry. We used a non-steady-state box model of the global sulfur cycle to show that the global δ(34)S record can be explained by variable marine sulfate concentrations triggered by basin-scale evaporite precipitation and dissolution. The record is characterized by long phases of stasis, punctuated by short intervals of rapid change. Sulfate concentrations affect several important biological processes, including carbonate mineralogy, microbially mediated organic matter remineralization, sedimentary phosphorous regeneration, nitrogen fixation, and sulfate aerosol formation. These changes are likely to affect ocean productivity, the global carbon cycle, and climate.

Links

Publisher Full Text

Authors

Wortmann UG, Paytan A

Institution

Geobiology Isotope Laboratory, Department of Geology, University of Toronto, Toronto, ON M5S 3B1, Canada. uli.wortmann@utoronto.ca

Source

Science (New York, N.Y.) 337:6092 2012 Jul 20 pg 334-6

MeSH

Carbon Cycle
Carbonates
Climate
Geologic Sediments
Minerals
Nitrogen Fixation
Phosphorus
Seawater
Sulfates
Sulfur
Time Factors

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.

Language

eng

PubMed ID

22822148