Deciphering the atmospheric signal in marine sulfate oxygen isotope composition
| Autor: | David T. Johnston, Emma Bertran, A. R. Waldeck, Boswell A. Wing, Itay Halevy, Benjamin R. Cowie |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
Biogeochemical cycle
010504 meteorology & atmospheric sciences Sulfur cycle 010502 geochemistry & geophysics 01 natural sciences Signal Isotopes of oxygen Atmosphere Atmospheric composition chemistry.chemical_compound Geophysics chemistry Space and Planetary Science Geochemistry and Petrology Environmental chemistry Earth and Planetary Sciences (miscellaneous) Composition (visual arts) Sulfate Geology 0105 earth and related environmental sciences |
| Zdroj: | Earth and Planetary Science Letters. 522:12-19 |
| ISSN: | 0012-821X |
| Popis: | Atmospheric O2 and CO2 levels inform us of the changes in chemical and biological environments, yet the history of atmospheric compositions, and pO2 in particular, is not well-constrained. The triple oxygen isotope (16,17,18O) composition of marine SO 4 2 − has been proposed to directly record the ratio pO2/pCO2 in the contemporaneous atmosphere. To resolve this atmospheric signal, both a precise measurement of the 17O composition of sulfate and a model with which to interpret the measurement are needed. Here we present precise measurements of the triple oxygen isotope composition of modern marine sulfate and then forward a novel sulfur cycle model that deconvolves the potential atmospheric and microbial inputs to this signal. Our interpretation of marine sulfate oxygen isotope composition provides a framework for calculating atmospheric composition, relative rates of biogeochemical activity, and can be applied to geologic records of marine sulfate to constrain the pO2/pCO2 ratio over time. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect