Spider
crab at Bastille vent where a Resistivity-Temperature-Hydrogen (RTH)
sensor was deployed. ROPOS positioned a sensor over the gray cone
to download data from the RTH.
Dive
R852 successfully ended at 1040 PDT after accomplishing all its primary
tasks. Samples (including gas tight and high temperature fluid samples)
were taken at Sully, Hulk and Bastille vents. Bastille vent is interesting
because it used to be devoid of vent animals, and the vent fluids were
of a higher temperature and different chemistry prior the 1999 Endeavour
earthquake swarm. Since the earthquakes the temperatures have dropped
up to 20 degrees and the vents are now covered with vent animals. This
is an example of the dynamic changes that are often occuring on the mid-ocean
ridges.
After
the dive, the ship transited to Cobb seamount to recover a current meter
mooring that was deployed two years ago. The ship then was en route to
Axial volcano to begin this year's NeMO research activities.
