Normally, when we look at the landscape around us (the natural one, that is), we see elements that were millions of years in forming. The Point Reyes peninsula in California slowly moving northward. The Grand Canyon being carved over eons. I could list more, but I’m running out of reasonable picture space in this post as it is…
Yellowstone is different. It is a place where geologic change is unpredictably predictable. We know it’s going to happen, we just don’t know specifically where or what the chafes will be. In fact, when the snow melts in Yellowstone, Park employees and others go around to find new features.
Some of that change is man made, usually when some “brilliant” soul throws something in a thermal feature. Don’t be one of those people. Usually, though, that change is cause by Yellowstone’s relatively unique position on top of a giant magma chamber. There are all kinds of books on the geology of this area (which I’m trying not to collect before I catch up on other reading).
Last week, I drove up into Yellowstone to visit the Mud Volcano area, which is much less visited than the geyser basins to the west, and which shows evidence of recent, dramatic change, even the peaceful-looking parts. Dragon’s Mouth Spring surges less now than it used to, and is not as hot. Even so, I could have stood there for hours listening to the roar of the steam and watching the surge of the little waves.
When Mud Volcano was first described, it was apparently a largish cone that shot mud onto the surrounding trees. At some point, it blew itself apart, and now it’s a blurping mud pot.
This hillside used to be covered in trees. In the late 70’s, many small earthquakes shook this area, and the soil heated to almost 200 degrees F. The poor trees were cooked and died.
Churning Cauldron used to be a cooler hot spring with pretty microorganisms on its surface. The earthquakes in the 70’s popped the temperature up and killed the critters. Interestingly, though, it didn’t start throwing water around until 1994.
The grayish water in the foreground is Black Dragon’s Cauldron. It has moved 200 feet uphill since it burst onto the scene in 1948. Sour Lake, in the background, has been much less active since then.
Across the street from the Mud Volcano area is Sulphur Cauldron, which is almost as acidic as battery acid. It’s in the foreground. See that peaceful hill towards the back right? That’s part of Sour Creek dome- a spot where the magma is pushing upward and making a hill.
Until we moved up to this area of the country, I had no idea that the area was this geologically active. I knew about Old Faithful and just assumed that all thermal features were that way, that it would take a major earthquake to change them. Now that I know how often features change there, I find myself fascinated. And trying not to stockpile geology books…