Abstract
High-resolution paired organic and carbonate carbon isotope chemostratigraphy of the Ireviken Excursion (Silurian) from the Altajme Core, Gotland, Sweden
Abstracts with programs - Geological Society of America, Vol.51(5)
Geological Society of America, 2019 annual meeting & exposition
09/2019
Abstract
The Silurian Period (443-416 Ma) was defined by extensive changes to the biogeochemistry of the Earth and marked by a series of extinction events and global carbon cycle perturbations. The Ireviken Event (Llandovery-Wenlock boundary, approximately 430 Ma) was one of these Silurian biogeochemical events and is marked by the Ireviken positive carbon isotope excursion. This global carbon cycle perturbation produced a positive carbon isotope excursion in both the organic and carbonate carbon records and this study is the first high-resolution investigation of the paired carbon isotope record through this interval. Upon examining the synchronicity between the organic and carbonate carbon records from this study, the data demonstrate a +2 ppm increase in Delta 13C, the difference between carbonate and organic carbon values, as well as a slight variation in the timing of the onset of events in each isotopic record. If taken as a proxy for atmospheric pCO2 concentrations, the data suggest an increase in CO2, and thus global temperatures. However, this is in opposition to previously published data using the oxygen isotope temperature proxy, which shows a roughly 4 degree Celsius cooling during this interval. If the oxygen isotope temperature proxy is considered to be valid, an alternative explanation for the Delta 13C record is required. One possibility is that changes to the fractionation coefficient of marine phytoplankton, epsilon p, driven by changes in global nutrient availability, could produce the changes seen in the delta (super 13) C (sub org) record, even in the presence of global cooling.
Details
- Title: Subtitle
- High-resolution paired organic and carbonate carbon isotope chemostratigraphy of the Ireviken Excursion (Silurian) from the Altajme Core, Gotland, Sweden
- Creators
- Emma R Hartke - University of IowaBradley D CramerMikael CalnerStephan C ObornyAlyssa M Bancroft
- Resource Type
- Abstract
- Publication Details
- Abstracts with programs - Geological Society of America, Vol.51(5)
- Conference
- Geological Society of America, 2019 annual meeting & exposition
- Publisher
- Geological Society of America (GSA)
- ISSN
- 0016-7592
- Alternative title
- Geological Society of America, 2019 annual meeting & exposition
- Language
- English
- Date published
- 09/2019
- Academic Unit
- Earth and Environmental Sciences; Office Of The Provost; IIHR--Hydroscience and Engineering; International Programs
- Record Identifier
- 9984230120902771
Metrics
9 Record Views