Do sedimentary sulfur phases link the biogeochemical cycle of calcium to atmospheric carbon dioxide concentrations?

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The weathering and burial of carbon and sulfur compounds controls the long term balance of atmospheric oxygen, carbon-dioxide, as well nutrient availability and uptake in the ocean. These so called biogeochemical cycles are controlled by physical processes like weathering, and microbial redox reactions in the sub-seafloor. While the carbon cycle is well understood, much less is known about the sulfur cycle. Since the amount of oxidized sulfur (sulfate) in the ocean is large, and the input and output fluxes are thought to be small, it is generally assumed that measurable changes to the sulfur cycle only occur over very long timescales (tenth of millions of years). Recent research shows however that sulfur fluxes can undergo large and fast fluctuations. Preliminary analysis shows that these flux changes are large enough to be able to affect ocean oxygenation and atmospheric carbon dioxide concentrations. Here I propose to explore these effects in detail to gain a better understanding how they e.g., affected glacial/interglacial carbon dioxide levels.