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18 April, 1999
It was a week ago that I frantically scurried about in order to make my
flight south.
A week has passed and we are still en route to the science though today is
the first day of the journey that I can say "we are truly at sea!" Gone
are the familiar green waters of the coast and in their place are the
deepest, purest blue waters I’ve ever seen. Even the roiling foam is blue
in the wake of the Nathaniel B. Palmer.
Today we have several talks lined up: Cara Wilson (InterRidge Office at the
Universite Pierre et Marie Curie in Paris, France) will speak about the
hydrography of Bransfield Strait (proposing a model for how its waters mix
based on information obtained in 1995, which she hopes to corroborate with
data from this cruise); Carol Chin (U.S. Ridge Office and College of
Oceanic and Atmospheric Sciences at Oregon State University - where many of
the team are from) will speak on hydrothermal activity in the straits; Sven
Petersen (Freiberg University of Mining and Technology in Freiberg,
Germany) will speak on the geological history of the Bransfield Strait and
economic geological implications of the work; and Randy Keller (also of the
College of Oceanic and Atmospheric Sciences at Oregon State University)
will speak on volcanic activity of the region. (I might add, post facto,
that the professional talks were a welcome and enlightening insight to make
for a collegial atmosphere en route to the research stations)
The research vessel has provided a community in itself. I feel very
fortunate to be here, surrounded by people who love the quest to know, to
explore. To them, it is the norm to question, to challenge, to measure.
It would be unusual to them to not, which is a twist on our daily
experience at home, as evidenced by the inane advertising slogan “Why ask
why?” I am never at a loss to find someone who isn’t eager to share
information on sample acquisition, data acquisition, analytical technique,
or data analysis questions that often leave one’s peers elsewhere with
their head askew and a quizzical look on their face. Whatever else I will
bring home, a reinvigorated and reaffirmed curiosity will be among my gains.
The willingness to answer questions and to place one’s educated scientific
opinion on the line follows in the venerable tradition of peer reviewed
science where hypotheses and views of scientists are formulated through a
dialectic process of suggesting, questioning, defending, and reformulating.
Today’s talks will no doubt involve opportunity for the input of others,
questions and long pauses as both questioners and speakers contemplate
implications of a parcticularly lucid question, an inevitable logical
consequence of a thought, or even the evolution of yet another line of
potential scientific inquiry that could easily occupy the pursuer for
another decade in research…
One such patient and very willing teacher has been Chi Meredith, of Oregon
State University. She is a materials engineer by training, out of Stanford
University, where she specialized in crystallography (the determination of
the structure of molecules by the patterns of light they give off when
illuminated). She came to OSU to study ocean sediments by X-ray
diffraction. She is now fully engaged in the chemical analysis of
seawater. On this trip, she will provide parcticulate matter analysis and
trace metal analyses of waters obtained near the vent plumes. In order to
obtain information on the kinds of parcticles streaming out of the plumes,
Chi will control a special pump that is aboard Dr. Klinkhammer’s ZAPS sled
(more on this later). When the ZAPS instrument indicates that it is within
a plume, Chi will send a message to the pump, which will turn on and begin
filtering plume water through a filter. After a set amount of time, the
ZAPS will be winched back to the surface where the filter will be dried and
prepared for analysis back in Oregon. There, in the lab, analysis will
involve comparing the mass of the filter before and after pumping the vent
water (total solids per liter can be determined from this by knowing the
volume of water pumped through). Next the filter will be ashed (burned)
and the residue will be dissolved in some very strong acids. Once this is
done, the resulting solution can be analyzed by ICPMS (inductively coupled
plasma mass spectroscopy can you find more about how this works? Email me
your findings!) and ICPES (no hints here, look it up!).
For the trace metal analyses, Chi will obtain water samples from
remote-controlled Niskin bottles that will go down open (top and bottom)
and then close upon command when the ZAPS instrument sled indicates they
are within the plume. Once the bottles are returned to the surface, Chi
will analyze the seawater samples for iron and manganese (two trace metals
that appear in much higher concentrations in the plumes of hydrothermal
vents, they will be analyzed separately) by a technique known as flow
injection analysis. In this technique, the seawater is treated with a
chemical that has a parcticular color by itself and a different color when
it binds with the metal. By shining different colors of light through the
solution and measuring how much is absorbed, it is possible to determine
the amount of the metal in solution (just like you can tell which kool-aid
is stronger by how dark it is).
I am putting the final touches on this journal entry. Word is we will be
on station at 7 AM tomorrow. We will attempt to snag a “bottom-lander,” an
array of equipment from a previous mission used to log ocean pressures 1000
meters down. We are then to proceed to a sampling site between Elephant
Island and Clarence Island to conduct ZAPS and CTD analyses (CTD is a
conductivity and temperature-measuring tool, deployed via tether and
controlled remotely). It will be a busy day tomorrow, we will probably
work through til 6 AM Tuesday morning. I will update you as soon as
possible. I’ll try to give you a more detailed description of the analyses
(ZAPS, CTD, rossette) as time permits.
OK, ‘til later,
Shawn Beightol,
Chi Meredith prepares to analyze for Manganese while Geraldine Sarthou of Geomar looks on.
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