Yesterday it rained all day, so we drove to Yellowstone National Park to take a look at the geology there. Yellowstone is most famous for its geothermal features, such as the mudpot shown above. Most of Yellowstone is a gigantic caldera, a collapsed volcano; the magma chamber under the volcano is the source of heat for the geothermal features. A large part of the caldera is now filled by Yellowstone Lake:

The most spectacular of these geothermal features are geysers, in which boiling water erupts at the surface. Below is a video of Steamboat Geyser (Quicktime required):

Notice the falling snow in the video. There has been a lot of snow in Yellowstone this year, which is quite visible along the roads:

Notice that the snow layers above are stratified – there is a different layer for each snowfall.

Yellowstone also has spectacular river features, including numerous waterfalls like Yellowstone Falls:

Here is an amazing series of oxbow lakes along a meandering stream:

Of course, besides its geology, Yellowstone is also famous for its wildlife:

This morning dawned cold but sunny, so right after breakfast we’re heading back out to the excavation site for more digging.