The R/V Thompson ~ 300 miles offshore as it works above Axial Volcano during the Visions'11 cruise.
The Thompson Heads Home
After three weeks at sea, the R/V Thompson turned east yesterday for the 28-hour steam home. This cruise has been incredibly busy and as we head home it is a good time to reflect on the accomplishments of this expedition and the humbling gift of having the opportunity to do what we do. We are honored to be able to work with the fine teams of both the R/V Thompson and the Canadian robotic vehicle ROPOS. Finally, it is with some sadness that the cruise closes and that our at-sea time with the 11 undergraduate and graduate students onboard is coming to an end. We have enjoyed sharing this experience with them and they have also enriched our lives out here. Some of our accomplishments include:
- Using ROPOS and their digital still camera, we successfully imaged the entire methane seep site at Southern Hydrate Ridge at unprecedented resolution. This led to the final site placement for the sensors and nodes– our main objective for Leg 1 of the cruise. Over 11,000 images were taken!
- We documented a collapse zone in the northwestern part of the field that formed since the last time we were here in 2010.
- A large nascent collapse area was imaged intensely, marked by a very large methane bubble plume. Burst pulsing of the bubbles resulted in further widening of the orifice while we watched – we believe this is the process that generated the collapse zone to the northwest.
- With twitter and the live video feed we began to build a community of viewers and citizen scientists that we much enjoyed interacting with.
- We directly imaged the entire ~26 km Primary Cable route from the base of Axial Seamount to the summit caldera – from this we made the major discovery of a significant hydrothermal field low down on the volcano’s flanks.
- The new hydrothermal field hosts active black smokers that rise >40 m above the surrounding seafloor, making them some of the largest deposits ever discovered.
- We drove myriad potential cable routes to best take advantage of what we learned on this cruise about the path, areal extent, intensity and style of the April eruption.
- Several new and impressive “snowblower” sites were documented by stunning high definition video showing the emission of significant amounts of biologically-produced material from the subsurface as a direct result of the eruption.
There were over 2 million hits on our web site, 257,108 page views, and in one week over 8 Terabytes of bandwidth was accessed on the VISIONS’11 website. Many thanks to all of our viewers and Twitter companions.