Do clay mineralss influence the burial and preservation of organic carbon on geologic timescales?

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The sequestration of organic carbon in sediments is one of the principle long-term regulators of the carbon cycle. It influences important parameters such as the level of atmospheric oxygen as well as the temperature of the biosphere through greenhouse gas regulation via CO2. The record of carbon burial in geological deposits identifies past perturbations in the carbon cycle and provides a critical perspective on the range of variation and insight in to the dominant controls. The purpose of this research is to investigate the mineral-surface-control mechanism responsible for carbon preservation in modern sediments and see if it applies to the rock record. This research involves the study of selected organic rich sediments from the Green River Shale, Monterrey Formation, and Ocean Drilling Program cores from the Demerra Rise in the Atlantic Ocean. These samples span a broad range of depositional environments, water chemistry, and diagenetic conditions. Mineral surface area, cation exchange potential, and organic carbon contents will be measured and examined for correlations. Sedimentary Fe and S and information on organic and isotopic biomarkers will also be used to examine depositional redox conditions. Broader impacts of the work are high and include international collaboration, strong integration of research and education that includes building a master's level course around the research project, and student training. The work also has implications for the exploration of petroleum source rocks.