9 December, 2001
Weather report: The trip to CONZ was postponed this morning due to weather. We really expected that no work would get done today. Wind chills were in the eighty-below range. But the weather did break, and the afternoon was 23 degrees below zero (C) with very little wind.
I left out one chapter in the SMELLING portion of investigating volcanoes--our windows into the active earth--by leaving out the research of Jessie Crain. (She has been mentioned other times in this journal.) This research involves the installation of pumps that pull gases from the plume. But the gases being filtered out are not the ones mentioned yesterday. They are radioactive.
Radioactive decay is a process by which one element changes into another element--not by chemical change, but by becoming fundamentally differennt. Sometimes the change takes thousands of years, sometimes less than a second. By this process, Uranium can go through multiple changes and wind up as lead. Some of the chemicals in this chain are very different than the chemicals that produced them. A metal, for example, might give rise to a gas. Jessie's work involves capturing one element in this chain of reaction that exists for less than a month. Since this element is produced as a gas, it bubbles up out of the magma chamber at a known speed. By measuring how much of the gas is left, some indication of the depth of the magma chamber can be deduced. Interesting Note: Jessie's samples are taken from our camp by helicopter to McMurdo, where they are placed on the next plane for New Zealand, then FedExed to Paris where they are analyzed.
Today I got a first hand look at the installation of instruments that FEEL the volcano. This is the science of seismometry. Most people are familiar with seismometers (seismographs) as they are used to detect the shaking of the earth during an earthquake. Seismometry can be related to the medical model of learning much as we saw with looking, or seeing. You can feel the earth shake during an earthquake, and you can feel the earth shake during a volcanic eruption, but seismomters look deeper, just like doctors look deeper with X-rays. Sound and pressure waves travel differently through solids and fluids, so when there is an eruption event, seismometers can detect differences in speed that offer a unique look into the make-up of the magma chamber. Where is the fluid? Where is the solid rock? What is the shape, depth, and size of the magma chamber? These are the questions being addressed by seismometry.
Today, we took another trek to the top of the mountain carrying heavy gear to install a seismometer on the rim of the crater. Science can be very hard work, especially when climbing at high altitudes. The installation was a success. But something else happened--the volcano erupted three times while we were there! Before you wonder why I can still be here typing this, you should know that not all eruptions are the same. This was not an explosive type of eruption (although Erebus does do that frequently). These were gas eruptions. Suddenly, and lasting for about a minute, the floor of the crater would erupt with a thunderous hiss, and clouds of yellowish vapor were thrust up into the atmosphere. Very impressive.
Final item: Please e-mail me if you have questions about the kinds of work being described so far. If you want to know more, or if you don't understand--ask!
Contact the TEA in the field at .
If you cannot connect through your browser, copy the TEA's e-mail address in the "To:" line of your favorite e-mail package.