Mt. Erebus from Observation Hill, Ross Island, Antarctica
I am settling in to life at McMurdo
Station as we wait for the first core samples to be brought to Crary Lab
from the drill site, which is about 25 km to the NW of McMurdo Station. While
we wait and get organized some of our team took a break and went for a walk
up Observation Hill (elevation 230 m). From the top of Observation Hill we had
a wonderful view of Mt. Erebus (elevation 3,700 m or 12,100 ft), a volcano
that is about 40 km away from McMurdo at the edge of the Ross Ice
Mt. Erebus is part of a group of volcanoes that make up Ross Island, the area
of land that McMurdo Station and Scott Base (the New Zealand Station) are built
on. Mount Erebus has been active since about 1.3 million years ago, and as you
can see from the small plume of steam above it, it is still active. If you go
to the Mt.
Erebus Volcano Observatory you can learn more about Mt. Erebus. They do
not have the live volcanocam set up yet though – they have to wait until November
or December when the weather improves and the research team gets down here.
Are you surprised to find that there are active volcanoes in Antarctica?
For geologists like myself it isn't a surprise, because we know that the volcanoes
are an indication that there is some kind of tectonic
activity, where the plates are colliding
or being pulled apart. Remember that even though it is cold here, the rocks
under the ice are still part of the outer layer of the earth (the lithosphere)
that makes up the tectonic plates, and these
plates move. Geologists that work on Antarctic Volcanoes have interpreted
volcanoes such as Mt. Erebus
to have formed as the crust that makes up the Ross Sea and West Antarctic area
has been stretched to form a rift basin, and the magma
moved up from below. The magma that fed these volcanoes may also have been influenced
by what geologists call a mantle
plume or hotspot. They are working to understand this better.
We should be busy working on the core by the next time I send you a postcard.
Do check out the Andrill
ARISE blogs to find out more about the things our team has been up to.
Bye for now!
Postcards from the Field: ANDRILL