Precruise efforts for Leg 2
During Leg 2 of the Gulf of California expedition, the scientists will be undertaking an ambitious sampling and instrumentation program of high temperature hydrothermal chimneys in the Guaymas Basin. The primary targets are structures called Rebecca’s Roost and Robin’s Roost that have been described and sampled on previous submersible and ROV expeditions. Although other groups have worked in this area, the last program was over two years ago and the structures may have changed. Also, this will be the first experience in this area for the ROV Tiburon pilots.
image shows Debra Stakes with the pilots in the ROV control room on the
R/V Western Flyer reviewing a video compilation of two previous
expeditions to the same site. Chief Pilot Buck Reynolds (center in hat) is
sitting in the chair occupied by the Chief Scientist during the ROV dives.
The scientists met many times, both in person and via teleconference, to put together a plan for the dive program. It became obvious that the scientific goals could not be met without using elevators to bring instruments to the seafloor and to carry samples and samplers back to the surface. We worked with a smaller elevator during the Juan de Fuca dives last August but needed both a larger volume and more secure elevator for this mission. Michael Conway and Randy Prickett of MBARI Operations designed, built, and tested a custom elevator for Leg 2 and a second elevator for Leg 5.
For Leg 2, the basket has special clamps to secure the Woods Hole Oceanographic Institution water bottles in each corner. There is enough space in the basket for a biobox to hold additional samples as well as a basket of extra push cores for sediments. The buoyancy of the elevator was carefully calculated and the entire system was weighed in water in the test tank. The elevators will be especially critical to recover all the equipment and samples during the last dive on Leg 6.
The Leg 5 elevator hovers over the top of the test tank. Randy Pricket (in the blue hard hat) is operating the controls. Mike Conway (center) and Mike Kelley (on the right) are the divers shown in the video (see below).
Click the movie icon for a short .avi video taken through the window of the test tank at MBARI. (It may take some time to download.) The Leg 5 elevator deployment and release is being tested. The vertically mounted barrels are for the vibracoring system that will be used to collect longer sediment cores during this program.
The new elevator built for the Leg 2 program. Note the large dual basket with clamps on each corner.