20 August, 2001
This morning we met as a team. Present were:
1. Dr. Philip Kyle, Primary Investigator. Principal investigation: Sulfur
dioxide emissions, GPS installation, supervision of the entire project
2. Christina Carver, graduate student. Principal investigation: Carbon
dioxide emissions
3. Jesse Crain, graduate student. Principal investigation: Gas sampling
for the presence of radioactive nuclides
4. Emily Desmerais, undergraduate student. Principal investigation:
installation and restoration of global positioning units
5. Richard Esser, technician. Principal investigation: restoration of power
to defunct seismic units and video cameras
6. Tim Vermaat, TEA: Principal investigation: maintaining weather station
and recording weather data, general assistance, crystal collection
7. Dr. Jeff Johnson (absent) Principal investigation: setting up equipment
for the sampling of acoustic data on Mt. Erebus
Introductions were made, after that a roundtable discussion of goals and
duties, followed by some considerations of dates and travel logistics.
When I consider what must be involved in organizing a research trip to
Antarctica, it seems quite daunting. It was both interesting and reassuring
to see how easily (perhaps smoothly is a better word) things go when you’re
working with a thirty-year veteran. In addition, three of the remaining
members have been on the ice before.
I met with Jesse Crain in the afternoon. When it was briefly stated in the
morning meeting that she would be looking at radioactive nuclides, I assumed
that she was into nuclear science. While it’s a part of the process, it’s
not the center of her research. Here’s the story:
In the fourteen-step nuclear decay of Uranium 238 to Lead, there is a
sequence near the end in which Bismuth 210 appears. It only has a half-life
of 5 days, so analysis must be done quickly. (The amazing part of that
dilemma is that the analysis is done in Paris! The sample is whisked off
the mountain by helicopter to McMurdo, flown to New Zealand, and Federal
Express takes it from there to Paris. Remarkable.) The central theme of
this sampling is that this data can be plugged into a model that predicts
the physical parameters of the molten insides of the volcano—its depth and
volume in part, but also the rates of recharge and convection that are
occurring within the body of magma. How? Beneath the surface of the lava
lake, gas bubbles form. Only half of the radioactive isotopes in the
Uranium decay chain are volatile at Erebus’ 1000 degree Celsius temperature,
but Bismuth is one of them. Once the bubble forms, it makes its way to the
surface. During this time, its decay continues. Knowing the density and
viscosity of the type of lava (anorthoclase phonolite), the rate of ascent
of the bubbles can be calculated. Other formulae can be used to establish
the relative quantities of the other parts of the chain of nuclear
decay—including those that are not volatile. It’s not as cut and dry as
that description makes it sound, and there are other applications for the
data that she will collect, like the processes of magma genesis and
transport, and its recharge, or convection. The importance of investigating
radioactive nuclides is that it gives scientists a window on the time frame
in which these processes are taking place.
Tomorrow I’ll talk with Phil about his remote sensing of the content of
sulfur dioxide in the plume of the volcano. (This data is correlated with
Jesse’s in some way that hasn’t been explained to me yet.)
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