1: What on Earth is a Core?
Ocean drilling samples are recovered in cores, long tubes of material collected while drilling beneath the sea floor. Specific terminology is used to precisely describe the location of a sample taken in a core.
Leg, Expedition : During the history of ocean drilling, the science has been carried out in segments called legs during DSDP and ODP and expeditions during IODP.
Site, Hole : A site is a location at which drilling is conducted. Drill sites are numbered consecutively starting with the first drilled by the Glomar Challenger in 1968. If more than one hole is drilled at a site, each hole receives a different letter suffix (A, B, C, etc).
Core : Each cored interval is usually 9.5 to 9.6 meters and 6 cm in diameter.
Section : A core is cut into sections 1.5 meters long, numbered from the top of the core.
Interval : A sample from a core is designated by distance in centimeters from the top of the section to the top and bottom of the sample removed
Visit "What on Earth is a Core" on the JOIDES Resolution webpage (http://www.joidesresolution.org/node/266) for a collection of resources explaining cores and core drilling.