Origins ANTARCTICA, Scientific Journeys from McMurdo to the Pole
Ideas Tools Place Live Field Notes
 

Looking down into the lava lake of Erebus.

   

Five senses on Erebus:

Examining the heart of the volcano.
by Noel Wanner and Paul Doherty

December 31, 2001

Watch an infant explore a strange object: they'll look at it intently, touch it, shake it, put it in their mouths-- almost anything that will help them determine what this new thing might be. Scientists, in their quest to undestand the world, are not so different from an infant in their curiosity; it's the tools which are different, tools which scientists use to extend their senses out into ranges far beyond human, to levels of precision far beyond sense impressions like "this tastes salty."

During a two-day blizzard on Mount Erebus, with temperatures near -35 C (-30 F) and winds over 45 mph (57 kph), creating a wind chill of -90 F, we had plenty of time to meet the scientists on Erebus. They were using instruments to extend all of their senses to explore the geology of Erebus, to try to understand the "life" of this volcano.

 

RichEssen waits out the storm.

 

See: Rich Esser is the webmaster of the MEVO, Mount Erebus Volcano Observatory, website. He works with scientist Bill McIntosh to maintain the live webcamera on the rim of Erebus. The video images are used by scientists to find the exact time of volcanic eruptions. The time is used together with seismic data to probe the structure of the rocks beneath the volcano.

Listen: Jeff Johnson is a geologist and mountain climber, he installed a wide frequency range microphone on the summit cone of Erebus. This microphone was sensitive in the subsonic frequency range. These frequencies of sound are emitted during volcanic eruptions, they do not get absorbed by the air and provide another means of timing the eruptions.

Taste: In the past scientists have done chemical analysis of the rocks on Erebus. Crystals grow in the magma beneath Erebus and get spit out of the mountain inside glassy volcanic bombs. The glass quickly weathers away leaving the mountainside covered in crystals. Analysis shows that the crystals covering the mountain are feldspar crystals that are rich in sodium and potassium, they are also found on Mt. Kenya. These crystals are coveted by almost everyone at McMurdo Station.

 

Jessie Crain sets up her "bionic nose".

   

Smell: Several scientists were smelling Erebus! Graduate student Jessie Crain pumped air through filters and collected radioactive particles and gasses. These radioactive materials are sent to Paris where they will be placed into particle counters. The counters will reveal the radioactive isotopes in the plume of Erebus, and thus tell how long the magma had resided in the magma chambers beneath the volcano. Graduate student Tina Calvin plans to fly in a helicopter through the plume of Erebus to suck up volcanic gasses from the plume and then measure the carbon dioxide gas concentration in the plume. Carbon dioxide is one of the crucial "greenhouse gases", which help to determine the Earth's temperature, so understanding the roles volcanos play in releasing Co2 is important.

Feel: Bill McIntosh is installing new broadband seismometers which radio their seismic information down to McMurdo Station to be recorded and forwarded to New Mexico. These seismometers feel the wavelike vibrations of the surface of the mountain generated by earthquakes and eruptions. These "seismic waves" show scientists the internal structure of the volcano. Bill also got the new wind generators on the mountain to work, to provide power to the instruments during the long Antarctic night.

Where am I? Inside your inner ear you have sensors which detect your orientation in space. Undergraduate Emily Desmarais uses a tool called GPS to perform a similar function, determining Mt. Erebus' changing position. (GPS stands for Global Positioning Satellite.) Desmarais has installed GPS recorders around the mountain. These recorders monitor the position of the outer surface of the volcano to within a few centimeters (a few fingerwidths). When the magma chamber beneath the mountain fills or empties, the surface of the mountain responds, expanding and contracting, just like your chest bulges out when you breathe.

The Brain In the body all of the sensory signals feed into the brain to be processed. On Erebus, Professor Phil Kyle of New Mexico Tech is the principal investigator. He advises on the science being done by his crew, and then helps them put together the observations into a picture of the inner workings of Mt Erebus. Every year the picture gets a little bit better,but it is never perfect -- so the scientist keep observing, hoping to learn more.

 

field notes
 
Origins Exploratorium ANTARCTICA

 

© Exploratorium