Blueholes and sinkholes are ubiquitous in the tropics, and their sediment preserve records of environmental change. There is a poor understanding of how environments in blueholes change during Holocene sea-level rise. Quantity and type of organic matter deposited are closely related to environmental conditions at time of deposition. Three main factors likely impacting organic matter accumulation: (1) primary productivity from the water, (2) hydrographic conditions in the bluehole which impact the rate of decomposition, and (3) Holocene sea-level. How does sedimentary organic matter document paleoenvironmental change in Freshwater River Bluehole through the Holocene?