Funds are provided for the project that aims to improve quantification of long-term particulate organic carbon (POC) decomposition in marine sediments. The PI will conduct a global survey of POC data collected by DSDP, ODP, and IODP to test models relating sediment age and temperature to POC decomposition rates, which will be averaged separately for different environments. Results will provide constraints on marine methanogenesis and the carbon cycle budget. The study hopes to advance understanding of the long-term organic carbon cycle, which plays a role in climate change. Two undergraduate students will be involved in the research, one of which will be recruited from a Consortium for Ocean Leadership program that targets underrepresented minorities.