They keep repeating this process until the drill pipe reaches the ocean floor. On Expedition 400, we are drilling in relatively shallow water near Greenland, with our shallowest site a little over 500 meters beneath the surface and our deepest just under 2,000 meters deep. Math challenge: How many 30-meter sections of pipe are needed to pass through these depths and reach the sea floor?
Fun fact: The deepest water the JOIDES Resolution has drilled in was 5,968 meters deep in the Mariana Basin, and the deepest sediment ever recovered was collected 1,927 meters beneath the seabed off the coast of New Zealand!
The crew uses several drilling techniques to push or rotate the steel pipe approximately 10 meters into the sea floor. A 10-meter core barrel, with plastic liner inside, captures the sediment layers. The crew then uses a smaller winch (coring winch) to bring the core barrel back up to the surface. The crew pulls out the plastic liner with core inside (hopefully) and hands it off to science technicians who begin processing it right away.
STEP TWO
When the overhead speakers announce "Core on deck!" science technicians put on their safety equipment and go to the core receiving deck (also known as the "catwalk"). The drillers pass off the fresh sediment core within the plastic liner, and as a team the technicians carry it onto the catwalk, where they start processing it right away. They take several steps to label, measure, and cut the core into 1.5-meter-long sections. There are also a few samples taken by scientists at this point. Then the core is moved into the lab where it is placed in racks to warm up to room temperature, about 20 degrees Celsius.
