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Updated: May 27, 2026
09:31
Preparation of Authigenic Pyrite from Methane-bearing Sediments for In Situ Sulfur Isotope Analysis Using SIMS
Published on: August 31, 2017
Application of sulphur isotopes for stratigraphic correlation
Adina Paytan1, Ellen T Gray, Zhongwu Ma
1Institute of Marine Sciences , University of California, Santa Cruz, CA, USA. apaytan@ucsc.edu
Isotopes in Environmental and Health Studies
|November 19, 2011
Summary
Seawater sulfate sulfur isotopes fluctuate significantly over geologic time. These rapid changes enable precise stratigraphic correlation of sediment sections, especially in deep marine environments lacking other dating methods.
Area of Science:
- Geochemistry
- Paleoceanography
- Stratigraphy
Background:
- Seawater sulfate sulfur isotopic composition (δ³⁴S) exhibits considerable temporal variation.
- Distinct intervals show high rates of isotopic change, offering potential for geological correlation.
Purpose of the Study:
- To investigate the utility of sulfur isotope fluctuations in seawater sulfate for stratigraphic correlation.
- To assess the age resolution and applicability of sulfur isotope records in marine sediments.
Main Methods:
- Analysis of carbonate-associated sulfate (CAS) and marine barite to reconstruct past seawater δ³⁴S.
- High-resolution dating of sediment sections to establish age models for isotope records.
Main Results:
- Sulfur isotope records achieve age resolutions of 1-5 million years (Ma), with some intervals reaching <0.25 Ma.
- Rapid isotopic fluctuations and excursions are identified in specific geological time intervals.
Conclusions:
- High-resolution sulfur isotope excursions in marine sediments serve as valuable stratigraphic markers.
- This method is particularly effective for correlating deep marine sections lacking biostratigraphic control or sufficient resolution.
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