Diving in the International District Vent Field

Share on facebook
Share on google
Share on twitter
Share on linkedin

Last night's weather conditions, with sustained winds of up to ~30 mph over the past 24 hours, precluded the launch of the ROV ROPOS.  These winds are not atypical of the NE Pacific at this time of year and the 10-foot waves were just enough to keep ROPOS out of the water. Because of this the ship time was used to conduct a bathymetric multi-beam sonar survey covering 130 square miles at Axial Base. This was followed by CTD casts throughout the early morning hours in the area where two instrumented moorings will be installed at Axial Base. These casts were performed to characterize ocean-water parameters (e.g., salinity, temperature, oxygen, and biological properties) in the profiler deployment area.

Meanwhile, onboard the ship, the engineers tested three junction boxes and a variety of instruments (bottom pressure/tilt meter, mass spectrometer, digital-still camera) were moved onto the deck for testing, with installation scheduled for follow-on dives.

The weather goddesses shined on us by noon, and we were able to go back into the water with the ROPOS, diving on the beautiful International District Hydrothermal Field. During the dive (R1713), the ROV surveyed the El Gordo (the big one) vent where we anticipate that a mass spectrometer, digital-still camera, and fluid sampler will be installed. Temperatures at this site were taken and reached 190°C (374°F). A gas-tight fluid sample was taken by Giora Proskurowski for analyses of the gases in these fluids. ROPOS then transited to the vent called Escargot and took a temperature that reached 271°C (520°F) and another gas-tight sample. With the weather continuing to improve, a short video survey was conducted on the largest structure in the field, El Guapo (the handsome one), which stands nearly 60 feet above the seafloor and vents boiling fluids.

With continuing improvement in weather, the R/V Thompson is now transiting back to the base of the volcano to begin installation of a junction box and a 1-km (~3300-ft) length of cable.