This winter our Cub Scout troops had the privilege of
visiting the Permafrost Tunnel Research Facility just outside of Fox, Alaska. It was a chilly neg. 20 degree morning and we
all gathered at the visitor’s center to learn more about the tunnel. The tunnel was first excavated back in 63’ to
learn more about permafrost, and ice studies.
They showed us pictures of what was used to excavate the tunnel and of
course we discussed safety issues. Then
we went to another building for our hard hats and headed to the tunnel. Learning about permafrost is very important,
especially in an area like Alaska. The
information I read there said that 35% of the earth is covered in
permafrost. Permafrost is when the
ground is permanently frozen, it does not unthaw during the winter. She showed us a sample taken from the tunnel of defrosted
permafrost and it was mostly murkey
water. In the past in Alaska, people
would build their homes, streets and buildings on permafrost, thinking that they
were on solid ground. But as time went
on their houses and streets started to sink. The houses were warm and the warmth of the
houses melted the permafrost under them, the permafrost is mostly water, so the
houses would sink. That is why in some
parts of Alaska you will see houses and buildings on blocks, so that heat can
escape without melting the permafrost.
As we got to the opening of the tunnel we could smell a
strong smell of decay, it was amazing that even though the cave is about 28 degrees,
there was a very strong smell. It was
amazing to think that as we entered into the tunnel we were stepping back into
time 14,000 years ago! At the beginning
of the tunnel we could see bones of animals like mammoths and bison buried in
the walls!
Then we continued into the tunnel. The farther we went, the farther back in time
we went. We went down a tunnel that took
us 65 feet below the surface and was formed 45,000 years ago. You could see roots and sticks still
preserved from plants that lived thousands of years ago, we even saw GREEN
dried grass! The tunnel walls had a fine
silt that if you rubbed your hands across would come loose. Because the environment was so dry the water
evaporated from the soil. The dust if
kicked up went every!
We had to wear a hard hat because parts of the ceiling of
the tunnel would fall, like rocks, pebbles and dirt. The ceiling in some spots was so low that if
you hit it with your head clumps would fall down on you. I did this by accident and some landed
on the back of my shirt and hair. Let’s just say that for the rest of the day,
until I could get home to take a shower, I could smell the decay. Deep in the cave we got to see ice wedges,
these take thousands of years to form and the biggest one that they showed us
they estimate took 3000 years to form.
An ice wedge is a crack in the surface of the earth caused by
stress. In the spring that crack fills
with water and in the winter that water freezes, then stress causes it to crack
again, and in spring it fills with water and the water freezes again and it
cracks again and the whole cycle repeats itself until 3000 years and cycles
later you have a large ice wedge. This
tour really explained a lot of the geological formations in Alaska.
We all had a great time and we were very thankful for the
men and women who took time out of their day to show us this site. If you are interested in more information please visit Permafrost Tunnel
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