The first detailed study of marine sediments was done in the 1870’s. An expedition called
the “Challenger expedition” led by Sir Murray and Renard dredged the bottom of the
ocean systematically and described the sediments. They classified their findings into 5
major groups: red clays, carbonate ooze, silicic ooze, nodules and volcanic material. This
is quite similar to what we do today. We categorize the type of sediments mostly by their
source and composition. In the late 1940’s, the first recovery of a long core was achieved
and that introduced the possibility of investigating sediments over time. Shortly
afterward, a global ocean drilling program was designed and sediment cores are now
continuously collected from different oceanic locations.