A Geothermal Experience

Friday we went on a drive with Ms Kristie’s dad, Mr Bruce. He used to be a tour guide for Yellowstone, so he knew a lot about the park. He mostly talked about the hydrothermal features of the park. These features are the result of a millions of years old volcano that covered pretty much all of Western and Central America in ash. If it were to go off again is would be an extinction level event in the northern hemisphere. Fortunately we have at least another thousand years before it explodes.

All the features can be lumped into one of four basic categories, geysers, mud pots, hot springs and fumaroles. Some of the features change what kind they are depending on the time of year, while some stay the same. New ones are constantly popping up, sometimes in very inconvenient places. For example, there is a parking lot where they’ve had to fence part of it off because a fumarole popped up right in the middle of the parking lot!

Mr Bruce also told us about how to determine which type of feature you are looking at. Probably one of the most famous kind of feature, to qualify as a geyser a feature must have a source of water, and have a constriction in their plumbing that creates pressure to propel water into the air. The most famous geyser in North America is Old Faithful.

To count as a hot spring it must have a source of heat, a source of gas and a source of water sufficient to overflow the area where it originates. An example of a hot spring is the Grand Prismatic Spring.

A mud pot is essentially a hot spring, but it does not over flow. An example of this one is the Mud Volcano. This results in it being much more acidic.

Finally, a fumarole is different than all the other ones in that it can NOT have a source of water at all. The roaring mountain is one of these. They are also very smelly, though that is not a requirement.