Ring of Fire 2004

RING OF FIRE 2004

Volcano. For most people, the word conjures up images of remote islands and the improbable spectacle of fountains of molten rock. To ROPOS it means something else altogether...

Our latest adventure took us on a whirlwind tour of seven volcanoes in 37 days - all of them underwater. Working from just south of Guam along the Marianas Arc to just south of Japan, we visited a variety of sites that had earlier been identified as 'interesting' by NOAA scientists.

In 2003, using CTD scans (conductivity, temperature, depth), multibeam sonar and other instruments, a team mapped out temperature anomalies and changes in the chemistry of the seawater that are the signature of subsea volcanism. These underwater 'plumes' come from hydrothermal vents that reveal the presence of geologically active features under the seafloor.

This year the NOAA team went back, with ROPOS, for a closer look. ROPOS has been used to capture video of hydrothermal venting at many locations around the Pacific Rim. It is, fortunately, rare to witness an actual eruption event but we were in for an unprecedented string of rare experiences on this trip - including bearing witness to an eruption.

In fact every aspect of the submarine environment was explored - from dark and dangerous depths to the tops of seamounts where bright and colourful reefs reach almost to the surface.

At times, the view from our cameras gave the impression that ROPOS was diving in a giant aquarium. For the biologists on the team, the endless parade of fish, the corals and crustaceans were a visual treat, standing in stark contrast to the more sombre depths. On the other hand, the geologists found the manner in which the abundant life 'obscured' the view of the underlying strata somewhat annoying. They say you can't please everyone but we had a few surprises in store for the geologists as well.

The expression "something you don't see every day" is not one we use in this line of work. It would get 'old' pretty fast. That notwithstanding, we do occasionally encounter something that's strange even for us. In this case, a vent, apparently blowing bubbles (and smoke), at a depth of 1650 meters (5413 ft).

In fact, the 'bubbles' are likely not bubbles at all, in the conventional sense but fluid-filled spheroids. The fluid is thought to be liquid carbon dioxide. This material accumulated on vehicle surfaces in sticky masses and apparently damaged the acrylic viewport on our main colour camera. We are pleased and proud to have been selected to provide our vehicle and support services to NOAA's Office of Ocean Exploration for this dive series. Over a period of almost six weeks, ROPOS performed extemely well, exceeding the requirements of a rigorous dive schedule with no down-time and minimal maintenance.

For further information on this venture, please visit NOAA's excellent website: Submarine Ring of Fire 2004.

Telephone: 250 363-6332

May 31, 2005