How do we use cores for research?

Deep-sea sediments contain microscopic fossils of marine animals, volcanic glass, sands and minerals originally from land (terrigenous material), cosmic material (microtektites), and other unusual materials unique to a marine environment (such as manganese nodules). The microfossils -- foraminifera, radiolaria, diatoms, etc. -- are important as time and environmental indicators; they are very sensitive to slight changes in temperature and chemical changes in their environment. Volcanic glass is an important "time marker" and records instantaneous geological events. Sands can indicate the presence of ocean currents, tell of ancient shorelines, reveal a past dust storm, or record submarine slides which might indicate submarine earthquakes. Deep-sea samples hold a permanent record of magnetic history revealing to scientists the ever-changing magnetic orientation of the poles.

Today we will explore one way cores can tell a story about climate using minerals, volcanic glass, and microfossils.