Gas companies and a supervolcano

Gas companies must love Yellowstone National Park! Today, along with hundreds, possibly thousands of other people, we drove around the western half of Yellowstone looking at geysers. We drove 330km!

Yellowstone National Park is actually a huge super volcano that will one day erupt. It sits over a body of magma which is 60km long, 30km wide and 5 to 12km deep. This is rather scary if you stop and think about it. The ground, which is the floor of the caldera is continually rising, small earthquakes are very common and the geysers are a symptom of all this volcanic activity.

Old Faithful is the most famous of all the Yellowstone geysers. It has a huge visitor centre and hotel development around it. It is located in an area of barren terrain which you can walk around on boardwalks - not really all that interesting to look at. This is it simmering away about an hour before the next predicted eruption of steam which happens 17 times a day and averages 40m in height for 1 to 5 minutes. If you look closely you can see all the rows of seats for spectators and several dozen already waiting. We didn't bother hanging around. We had other stuff to go see (and we have already seen a geyser erupt in New Zealand. Not quite as big as Old Faithful but we got to sit much closer.)

A lot of the geyser locations just have some barren ground, some steam, occasionally boiling water and dead trees. What is impressive is the sheer size of the area over which they occur. Here a couple of the more visually interesting things:

Black Sands - geyser erupting about 10 to 15 metres in height right on the edge of a stream. The water must be quite warm for the fish - and there are fish in this river, as we drove along it for quite a distance and saw lots of people fly fishing.

This is the Lower Terrace of Mammoth Springs. It is like a boiling waterfall solidifying as the water deposits minerals and particles. It sounds like a boiling kettle and looks like a huge waterfall or a limestone cave formation. There is water flowing over the top but most of what you see is solid rock.