cruise plans technology education participants calendar
Science News:
June-Aug. 2000
 25 26 27  28 29 30 1
2 3 4 5 6 7 8
9 10 11 12 13 14 15
16 17 18 19 20 21 22
23 24 25 26 27 28 29 
 30 31 
 2  3 5

NeMO Date: July 8, 2000
Ship's Location: 45 56.0'N/129 58.9'W

  Science Report:
Perspective on NeMO 2000
from the Chief Scientist

I am sitting here in my cabin 1500 meters (about 1 mile) above the caldera of Axial Volcano anticipating the next dive with the Remotely Operated Vehicle ROPOS. Fourteen years ago, several of us on this expedition (Dave Butterfield, Verena Tunnicliffe, Keith Shepherd, Bob Holland, and myself) took part in dives with the Canadian PISCES IV manned submersible that mapped and sampled the ASHES vent field and made the first dives to the east side where the 1998 eruption took place. This work was one of a series of expeditions that established Axial as a long term study site.

The concept of an observatory at Axial Volcano began to gather momemtum about 5 years ago after our first experiences with monitoring and responding to eruptions on the Juan de Fuca Ridge. I feel fortunate to have played a role in the inception and implementation of this program. Although we still have a long way to go to establish a realtime presence on a seafloor volcano, the NeMO program has made some real strides in making this a reality. The data sets we are collecting here following the 98 eruption are among the most comprehensive chemical and biological time series data ever collected from a seafloor volcano, and will serve as important benchmarks for future monitoring of the volcano.

Ensuring that this program comes together on a yearly basis since 1998 has been challenging but ultimately made possible only with the excellent collaboration of a range of scientists from both U.S. and Canadian Universities. Oceanography has always been a highly cooperative science while at sea, but the NeMO program has had to have an unusual level of communication in setting up the complex sampling program required for it to succeed as an interdisciplinary program.

The NeMO2000 program is continuing to collect a time series of data on the evolution of the chemical and biological systems following the eruption. At the same time, we are setting the stage for a more comprehensive monitoring of future volcanic activity. The establishment of "Bench Marks", places where repeated measurements can be made and compared for change over years, is a well-established technique for monitoring volcanos on land, and we are putting the first ones into Axial Caldera this year.

The development of realtime data transfer from the seafloor is being pursued with our NeMONet program. A camera and temperature sensor package will be deployed before we leave the site next week and is planned to provide a realtime data stream over the next year. Assuming this works, we can begin to plan on using this technology to monitor the effect of future eruptions and earthquakes. A major goal will be to establish a seafloor station for an AUV (Autonomous Underwater Vehicle) so that surveys and sampling can be directed to areas undergoing changes observed by the hydrophone monitoring system.

We are continuing to see evidence of the system cooling down to some baseline of activity that may represent the "between" eruption phase of activity. An MTR (Miniature Temperature Recorder) deployed at the Cloud Vent last year shows a rapid decrease in temperature over the first few months, leveling off to a constant temperature of about 16 degrees Centigrade until it was recovered. Some sites have become inactive since last year, and others show a reduced temperature. So far, NeMO2000 has been very successful, with a minimum of instrumental problems and excellent weather, and we can only hope for more of the same.

Bob Embley


Cloud Vent in the eruption area, is a hazy vent (hence the name). The rope in the foreground was used to attach the MTR which was recovered and the data is shown below.

Fissure just south of the 1998 lava flow, seen during Imagenex survey. About 1 meter wide, it was not present before the eruption, so horizontal extension during eruption was at least 1 meter.

Graph showing the one year temperature drop at Cloud Vent taken from the MTR. See report for full details.