♪MUSIC♪
MIKE GARCIA: Okay.
MILES O'BRIEN: If you want to learn what makes a volcano
erupt, you need to go right to the otherworldly source... the
crunchy, oozing, red hot source. At least that's what geologist
Mike Garcia does.
MIKE GARCIA: Voilà!
MIKE GARCIA: Wow! That's amazing. MILES O'BRIEN: Amazing indeed.
Welcome to the most studied volcano in the world: Kilauea.
Garcia and I came to this surreal landscape on
Hawaii's Big Island by helicopter. On our way, we got
a glimpse of the red rock cauldron of magma through the
sulphur-tainted steam. Kilauea is one of the longest currently
erupting volcanoes on the planet. The lava started flowing
in January of 1983.
MIKE GARCIA: So the mantle is producing enormous amount of
hot material that's coming out of Kilauea. This is probably
one of the most active periods of the historical
record of Kilauea.
MILES O'BRIEN: The eruption waxes and wanes... at times
spewing fountains of lava -- and in the 1990s threatening and
destroying nearby homes. Through it all, there is one constant
besides the flowing lava: Garcia. He's been studying
Kilauea for 30 years, thanks to support from the
National Science Foundation.
MIKE GARCIA: Well, with most volcanoes, you want to know when
it's going to erupt. And so that's a primary concern. But in
this case, where we have an eruption that's been going on
for over 30 years, the big question is, when is it
going to stop?
MILES O'BRIEN: He comes here looking for data -- in this case,
a piece of freshly cooked earth, just out of the oven. He dunks
it in water, freezing the moment and its chemical composition in
time -- a geological Instagram -- packed with data.
MIKE GARCIA: We know its birthday. We know when it was
erupted. And you might ask, well, why do we care? Because
the lava composition changes hourly, daily or even monthly.
MILES O'BRIEN: And somewhere in there might be some sort of
telltale sign of whether it's going to continue erupting
or not, right?
MIKE GARCIA: Absolutely. In science, one of the key things
we do now are time series studies, where we collect
samples repeatedly during the course of eruption or in the
ocean because it's evolving all the time.
MILES O'BRIEN: Back in his lab at the University of Hawaii in
Honolulu, graduate student Kendra Lynn does her part to
understand Kilauea, shaving rocks into 30-micron slices and
then analyzing them using an electron microprobe. She is
interested in this green mineral called olivine. It is the most
common mineral that forms at Kilauea. What can we
learn from it?
KENDRA LYNN: Because it's the first thing to crystallize in
these magmas, it tells us a lot about the mantle source,
where the magmas came from, and it can also tell us a lot about
the magma's history.
MILES O'BRIEN: This is just one of many tests the team
routinely conducts to analyze the elements and isotopes in
the newborn rocks.
MIKE GARCIA: Each of the processes within the volcano
leaves a fingerprint. So over the years, we've been able to
develop an understanding of what those fingerprints are and what
they tell us about what's going on in the volcano.
MILES O'BRIEN: So, where are we right now, what's this?
MIKE GARCIA: We're looking at the rock collection we have
from the Pu'u 'O'o eruption, as well as some of the
other Hawaiian eruptions.
MILES O'BRIEN:And over the years, he has amassed an impressive
collection of rocks, not just from Kilauea, but from volcanoes
all over the Hawaiian Islands.
MIKE GARCIA: So this is July 23rd of 1997. And this one looks
a little grayer.
MILES O'BRIEN: Yeah, it's not quite as shiny for whatever
reason. Why would that be?
MIKE GARCIA: But you can see the imprint. Well, it was a
little cooler at the time it was quenched.
MILES O'BRIEN: Ahhh, I see. If only these rocks could talk.
Fortunately, Garcia is pretty adept at reading them. One of
the things he focuses on is the temperature of the lava.
MIKE GARCIA: So, what we've seen is a long-term decrease.
Initially, the lava temperature was low. It increased -- the
eruption roared upward and now it's been slowly waning as... and
we see the temperature of the lava is indicating a decrease.
So we think this eruption might end in the near future. But,
it's ended several times in the past. It was quiet in 1997 for a
month, and then it restarted.
MILES O'BRIEN: Back at the lava flow, Garcia told me his work is
not as dangerous as it seems -- a calculated risk for a good
scientific cause. All right, so, what is the strategy for
walking? How do you know what to step on?
MIKE GARCIA: We need to avoid areas that look shelly,
indicating that the lava has drained out from underneath. So
we try to look for places where it looks solid, so we can avoid
collapsing in on the lava flow.
MILES O'BRIEN: I'm just gonna follow you. How's that?
MIKE GARCIA: Very good.
MILES O'BRIEN: But while we were here, some newly minted,
still hot Hawaiian earth melted the soles right off his
shoes. Wow! Just like that. Is the other one already gone?
MIKE GARCIA: No, no. Oh, you're absolutely right! Holy-moly. Wow!
MILES O'BRIEN: All in a day's work for an
intrepid geologist determined to go with -- and to -- the flow.
MIKE GARCIA: Success!
MILES O'BRIEN: For Science Nation, I'm Miles O'Brien.