Oceans cover 71% of our Earth. Formed over 3.8 billion years ago, these vast depths could hold some of the answers to our questions about Earth’s long and mysterious history, as well as offer predictions for the future of our planet. And the key might be found in, of all places, rocks.    On this episode of Access to Excellence, President Washington speaks with Geoffrey Gilleaudeau, associate professor in the Department of Atmospheric, Oceanic, and Earth Sciences Department in the College of Science, about the past, present, and future of Earth’s oceans according to the physical and chemical characteristics of sedimentary rocks.