Lighting up Axial Seamount Again

Wednesday, August 16, 2017
HD Camera Reinstalled at Mushroom
Mushroom Comes to Life

A shot of the newly installed HD camera lighting up the face of the actively venting Mushroom chimney in the ASHES hydrothermal field. Credit: UW/OOI-NSF/WHOI; V17.

We arrived at Axial Seamount after a 19 hr steam to find the seas a bit bumpy still. To use the time wisely until we could dive a deep water CTD cast was conducted to get additional measurements of ocean parameters to verify cabled mooring instrumentation and to obtain water that will be needed in the Cabled Array Lab to refurbish instruments next year. The dive was also used to conduct the “old time” tradition of taking Styrofoam cups and a head down to depth so that they would be shrunk by the overlying ocean water pressure that is almost 300 times that on land at the base of Axial Seamount.

The seas calmed enough to conduct Jason dive J2-1001 at th ASHES hydrothermal vent field with the high definition camera secured underneath the vehicle in the elevator. The elevator was set a safe working distance away. Jason conducted a “fly around” of the ~12 ft tall Mushroom structure where the 2016-installed camera is located and then the old camera was removed and the new camera installed near the chimney. It is a beautiful place to work in very clear waters with another tall venting chimney only 10 m away called Inferno. This year the summit of Mushroom “sprouted” two new “horns” on the top of the edifice composed of very fine-grained sulfide and a calcium sulfate mineral called anhydrite. Similar to previous years, cracks radiating away from the chimney were filled with white microbial mats and tubeworms obtaining nourishment from warm fluids gently venting out of the cracks.

The installation utilized some amazing technology involving telecommunication cables and a satellite. To install the camera as close as possible as last year (so that time series measurements can be made of changes in animal communities and to measure chimney growth), we had two live video streams on the ship being fed to us. The first stream from Jason was instantaneously fed through their fiber coming from 1500 m water depth. This stream was sent to shore via a telecommunications satellite 22,000 miles overhead at the equator, and then onto the Internet. When the camera on the seafloor was powered up, that stream was sent from >300 miles offshore and 1500 feet down along >500 km of the Cabled Array high power and bandwidth cables, coming ashore at the Shore Station in Pacific City, Oregon. From there the feed was sent to Portland Oregon, on to Rutgers University, to an uplink site for the satellite, to the satellite at the equator and back to the ship! While we saw a reduced resolution “live” stream, we have heard that the video, now being streamed live 9 times a day is stunning. Please tune in on the feed to watch it live.

On a follow-on dive we completed the installation at the ASHES hydrothermal vent field,  including the addition of a new cabled CTD and bottom pressure-tilt instrument. We also turned a 3D temperature array and osmotic fluid sampler in a diffuse flow site.

During a follow-on dive at the International District Hydrothermal Field there was a mechanical issue with the Jason winch and we are now heading into shore for repairs. We will arrive in Newport tomorrow.