NOAA Ship Ron Brown - ROV Cruise

ROPOS dive R628 returned to the CASM vent area to investigate geologic features on the seafloor that were mapped on dive R626 with the scanning sonar. The new map covers part of the caldera floor (where the vents are located) and part of the caldera rim (where the north rift zone intersects the caldera), but not the caldera wall itself so some additional dive time was used to survey that feature today. Suction sampling is currently being done at the CASM vents to collect microbial mat samples. Molecular analyses from one 1999 sample showed that the mat community at CASM is much different than found at other vent sites throughout the entire Pacific... More...

NOAA Ship Ron Brown - Jeff Goodrich

Excitement erupted last night in the ROPOS hydro lab as two new chimneys were discovered in the Coquille vent field. While scouting around for a vent fluid sample site we stumbled across two super-hot vents a few meters meters apart, approximately one meter high. Both are believed to be anhydrite chimneys and one had a temperature of 313 degrees Celsius, the hottest vent thus far on the cruise. Taking a sample of the vent itself was not possible. We didn't have anywhere to put it because the bio box was taken off so that the hot fluid sampler could be installed for the dive. The chimney material was too friable to be recovered in tact. Anhydrite, or calcium sulfate, is more soluble in cold than hot water. More..