We struck gold! A rare encounter with the underground!
For many years Alaska has been famous for gold. Many people came here during the early 1900s to mine for gold. These miners dug tunnels to find the layer of rocks that contained the gold. By the early 1960s, the mining companies wanted to test new mining equipment and started to make a new tunnel. This tunnel proved to be a "gold mine" not for miners but for scientists. It contains fossils of bisons and ice that trapped 40,000-year-old living organisms. Scientists are able to study geology, ice science, and biology of permafrost.
Cold Region Research and Engineering Laboratory
A snow covered cabin to a underground tunnel
What is permafrost? It is the layer of earth that stays frozen for at least 2 years. The top layer soil can be soft or unfrozen in the summertime and the layer under the permafrost can be warm as it receives heat from the layers below. But the layer in between is the layer that stays frozen. Sometimes there is not only frozen soil but also a frozen wedge of water.
A frozen layer of soil
This ice has trapped living organisms tha are 40,000 years old
The first part of the tunnel is well supported since it is not in the permafrost layer
Notice there are no supports in the permafrost tunnel as the walls are held by the frozen water and soil
A winter wonderland of ice crystrals as the entry way of the tunnel is refrigerated to keep the tunnel cold
A cold entry into the tunnel