Back into the ASHES Hydrothermal Field

August 28, 2011

Scaleworms, about 1 inch long, have already colonized the Marker 33 site that was covered by the April eruption. Also shown are dense microbial mats. Green lasers are 10 centimeters apart.

A small collapse zone north of the International District Hydrothermal Field showing characteristic bathtub rings and talus rubble that is the remanents of the roof.

An acoustic current meter deployed on a lobate basalt flow just south of the International District Hydrothermal Field

Rattail fish swims slowly in 2.4°C seawater at a depth of nearly 5000 feet beneath the ocean’s surface at Axial Seamount. Credit: UW/NSF-OOI/CSSF, V11.

This full-sized Junction Box frame was sucessfully deloyed and recovered in the International District Hydrothermal Field at Axial Seamount using the ROV ROPOS during the August 2011 VISIONS '11 expedition. During the VISIONS'13 cruise two fully built out medium-power J-Boxes will be deployed here that will provide power and communications to extension cables and sensors deployed at the vent sites. The sensors will include a digital still camera, mass spectrometer, fluid and DNA samplers, bottom pressure and tilt sensor, a temperature-chlorinity probe to measure boiling fluids exiting the vents, and a short-period seismometer.

Filamentous bacteria coat the outer surfaces of the sulfide chimney called Castle in the International District Hydrothermal Field on the eastern side of the Axial Seamount caldera. Warm fluids emanate from a small vent beneath Castle, supporting the microbial communities.

An anchor for an expendable transponder rests atop a pillow basalt flow. The transponder was recovered. Credit: UW/NSF-OOI/CSSF; V11.

ROPOS prepares to cut parachute cord that was attached to an expendable transponder. The transponder was recovered aboard the R/V Thompson.

A Flathead Sculpin (Psychrolutes phrictus) hovers in the caldera at Axial Seamount at a water depth of nearly 5000 feet beneath the ocean’s surface. Credit: UW/NSF-OOI/CSSF; ROPOS Dive R1470; V11.

Spider crabs are very sensitive to vibrations. This one, at 5000 feet beneath the ocean's surface at Axial Seamount investigated a monkey fist on a piece of equipment on the Canadian ROV ROPOS.

Today was a busy day with the termination of a very long dive that started last night and ended in the afternoon. The dive started in the International District Hydrothermal Field on the eastern edge of Axial's caldera wall. During the initial portions of the dive the full-scale test frame built by APL was successfully decoupled from ROPOS – another first. ROPOS then began a several-hour survey north to Primary Node PN3B to determine an optimal cable route from the International District to PN3B. Along the way fantastic imagery was obtained of various lava formations, collapse zones, and the new lava flow. Then, before traveling back toward the International District, ROPOS then spent a couple hours exploring possible alternate deployment sites for PN3B.

Along the way the vehicle made a brief stop at Marker 33, a diffuse flow site that was covered by the new lava flow, but which is now active again. We imaged the very dense microbial communities that have grown since the eruption as well as new, small colonies of palm worms, tubeworms, and scale worms that have already begun to colonize the site.

From Marker 33 we continued to the International District and recovered a temperature sensor from the high-temperature black smoker named El Guapo. We are most anxious to get a look at the temperature record to see if there have been any changes in vent fluid temperature prior, during, or after the eruption. We also successfully recovered a temperature sensor from a small pagoda-like structure at the base of El Guapo. ROPOS took an excellent sulfide sample from the top of El Guapo that will be studied onshore to understand which microbial communities live within the new growth and what metabolic functions they might have.

Dive 1471, late this evening and into the early morning hours of Sunday, will focus on the ASHES vent field. Here we will recover the Sensorbot array and camera, take some temperatures of the black smokers, and recover some microbial experiments.

The days are flying by and we are looking ahead to make sure that we accomplish all the tasks we set out to do at the beginning of the VISONS '11 program.