Fingerprinting Mississippi River Sediment Flux to the Gulf of Mexico

Samuel Munoz, Geology & Geophysics
Liviu Giosan, Geology & Geophysics



The Mississippi River’s delivery of freshwater, sediment, and nutrients plays a fundamental role in the coastal fisheries and marine ecosystems of the Gulf of Mexico.  Despite its environmental and economic significance, we have a limited understanding of why the Mississippi’s outflow varies from year to year.  Both climate variability and human modifications to the landscape influence sediment delivery, but it is difficult to predict and plan for the impacts of climate change on the Gulf of Mexico without information describing how the river behaved in pre-anthropogenic times.  A field program will be undertaken to acquire critical geological data from the major tributaries of the Mississippi River system that will allow us to build an initial radiogenic isotope database to ‘fingerprint’ sediment contributions from major tributaries.  This will provide the initial basis to understand the evolution of the Mississippi’s sediment flux over the last several thousand years in relation to natural climate variability.