Geology Update from Hawaii's
Mauna Loa
A previous news article in The
Citizen Scientist described the work of geologists
Julie Herrick and Erika Ronchin high on the slopes of
Hawaii's Mauna Loa, the world's largest volcano ("Geological
Science on Hawaii's Mauna Loa," 17 June 2005).
During their time on the mountain, students from the
University of the Nations visited the famous Mauna Loa
Observatory (MLO) during an annual field trip (Fig.
1). Several students found a deposit of white powder
of unknown composition in the lava about 10 kilometers
from MLO (Fig. 2). Erika Ronchin agreed to take some
of the powder back to her institution, the Universita
degli Studi di Trieste, Italy.
Recently Erika sent her chemical analysis
of the sample:
"I would like to thank you for
the article you wrote on Mauna Loa Mapping Project and
I would like to thank you for the photos you sent me.
I remember that I promised you the analysis [of the
white powder]...so here are the data:
| Compound |
Fraction |
SiO2 |
4.29% |
TiO2 |
0.04% |
Al2O3 |
0.46% |
FeO |
0.15% |
MnO |
-0.01% |
MgO |
0.66% |
CaO |
1.34% |
NaO |
93.01% |
K2O |
-0.049% |
P205 |
0.09% |
Ni |
-42 ppm |
Rb |
-6 ppm |
Cr |
-37 ppm |
Nb |
60 ppm |
Zr |
60 ppm |
Y |
11 ppm |
Sr |
11 ppm |
"When I made the analysis the
machine was set for the lava analysis, this is why you
can find some strange minus signs. Anyway, the most
important data is the NaO. I'm not an expert on gas
sublimation, but I think that the powder is sodium salt,
in this web site you can find some photos here.
When the lava starts cooling it releases a lot of gas
made of steam and alkaline chloride (mostly NaCl). Gas
sublimation condensed sodium salt."
Erika's results should be quite intriguing
for anyone who has visited the slopes of Mauna Loa,
whose lava ranges in color from burnt orange to pitch
black. Finding a snow white powder on those barren slopes
was a major mystery until Erika's data arrived.
Forrest M. Mims III 
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