Moon Pool

Hi crew:

I think one of the coolest things about the JR is the moon pool. The moon
pool is the large opening in the center of the ship that allows the drill
string, re-entry cones, and other equipment to pass through to the ocean
below. It is literally a large opening in the ship (probably close to 20 ft
across) with big heavy doors on the deck side that keeps it more or less
closed, and no door at the bottom; this is literally a bottom-less pool.
Anyway, on this particular sea trials expedition, one of the objectives was
to re-enter a hole that was drilled in 1990. In order to re-enter a hole, a
re-entry cone must be installed on the seafloor. This is the subject of
tomorrow’s picture of the day. In order to re-enter a hole that has a
re-entry cone, the drillstring is assembled to a point ~20 or so feet above
the seafloor (we know the water depth based on echo sounding, but also the
fact that ODP drilled here before and left a re-entry cone for us!). Then a
camera and powerful floodlights mounted on a sturdy frame are lowered down
the drillstring. I’ll tell you more about this process tomorrow. Today’s
picture shows the moon pool doors wide open and the camera sled securely
wrapped around the drillstring. It is about to be lowered to the seafloor.

Talk with you tomorrow.