We made it out to our first camp in the McMurdo Dry Valleys on November 3. The first day was spent making camp in Taylor Valley and since then we have been walking around the base of Stocking Glacier collecting samples from the terminal and recessional moraines deposited in front of the glacier. A moraine is a long narrow pile of rocks deposited at the end of a glacier as it melts away (see image below). Terminal moraines mark the farthest point a glacier flowed and recessional moraines mark the locations a glacier pauses during its retreat.
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| Diagram of a retreating glacier. Image shows terminal moraine and a recessional moraine. Other glacial features are labeled on diagram as well. |
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| Picture of one of the recessional moraines at the end of Stocking Glacier. This moraine is the most obvious moraine because it has a clear concentration of large boulders compared to the surrounding areas. |
Glacial moraines can be seen all over the world. Moraines occur in regions that have glaciers today and areas that used to have glaciers. Some good examples in New England include Long Island, NY and Cape Cod, MA. These two areas were formed from terminal moraines almost 21,000 years ago! These moraines in New England are much larger than the moraines we will be sampling in Antarctica. The moraines we are sampling at the base of Stocking Glacier are <1 km long while those in New England are 250-300 km.
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| : Illustration showing the location of terminal moraines near Rhode Island. Long Island, NY and Cape Cod, MA are both formed from large terminal moraines deposited during the Last Glacial Maximum. |
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