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Marked Decline in Atmospheric Carbon Dioxide Concentrations During the Paleogene
The relation between the partial pressure of atmospheric carbon dioxide (pCO2) and Paleogene climate is poorly resolved. We used stable carbon isotopic values of di-unsaturated alkenones extractedExpand
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Global patterns in leaf 13C discrimination and implications for studies of past and future climate
Fractionation of carbon isotopes by plants during CO2 uptake and fixation (Δleaf) varies with environmental conditions, but quantitative patterns of Δleaf across environmental gradients at the globalExpand
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Molecular Paleohydrology: Interpreting the Hydrogen-Isotopic Composition of Lipid Biomarkers from Photosynthesizing Organisms
Hydrogen-isotopic abundances of lipid biomarkers are emerging as important proxies in the study of ancient environments and ecosystems. A decade ago, pioneering studies made use of new analyticalExpand
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Miocene evolution of atmospheric carbon dioxide
Changes in pCO2 or ocean circulation are generally invoked to explain warm early Miocene climates and a rapid East Antarctic ice sheet (EAIS) expansion in the middle Miocene. This study reconstructsExpand
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Influence of physiology and climate on δD of leaf wax n-alkanes from C3 and C4 grasses
Abstract We measured hydrogen isotope compositions (δD) of high-molecular-weight n-alkanes (C27–C33) from grasses grown in greenhouses and collected from the US Great Plains. In both cases, n-alkanesExpand
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Transient Floral Change and Rapid Global Warming at the Paleocene-Eocene Boundary
Rapid global warming of 5° to 10°C during the Paleocene-Eocene Thermal Maximum (PETM) coincided with major turnover in vertebrate faunas, but previous studies have found little floral change. PlantExpand
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New insights into Archean sulfur cycle from mass-independent sulfur isotope records from the Hamersley Basin, Australia
We have measured multiple sulfur isotope ratios ( 34 S/ 33 S/ 32 S) for sulfide sulfur in shale and carbonate lithofacies from the Hamersley Basin, Western Australia. The v 33 S values (v 33 SWN 33Expand
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Fractionation of carbon isotopes by phytoplankton and estimates of ancient CO2 levels.
Reports of the 13C content of marine particulate organic carbon are compiled and on the basis of GEOSECS data and temperatures, concentrations, and isotopic compositions of dissolved CO2 in theExpand
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Late Archean rise of aerobic microbial ecosystems
  • J. Eigenbrode, K. Freeman
  • Environmental Science, Medicine
  • Proceedings of the National Academy of Sciences
  • 24 October 2006
We report the 13C content of preserved organic carbon for a 150 million-year section of late Archean shallow and deepwater sediments of the Hamersley Province in Western Australia. We find a 13CExpand
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Consistent fractionation of 13C in nature and in the laboratory: growth-rate effects in some haptophyte algae.
The carbon isotopic fractionation accompanying formation of biomass by alkenone-producing algae in natural marine environments varies systematically with the concentration of dissolved phosphate.Expand
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