There are so many of these thermal features that, in the five days we have been here, we have seen perhaps half of them, maybe less. This gives us another reason to come back some day.
On the first day, we saw, of course, Old Faithful. In fact, we saw it three times! It went off when we first arrived; then we had lunch and it spewed again; then we took a tour of the Yellowstone Lodge, and off it went again! I feel lucky.
I first saw Old Faithful 35 years ago. At that time, it would erupt regularly, once each hour, to the extent that a ranger told us he could set his watch by it. 35 years later, it erupts approximately once every 93 minutes, give or take 10 minutes. In other words, it is slowing down and is not quite as regular. Here is the obligatory photograph of Old Faithful, something you have all seen before, I am sure. It's eruptions shoot water into the air 130 to 180 feet high.
If I have learned anything about Yellowstone, it is that it is constantly changing. Geysers and hot springs come and go, or shift, or become quieter or louder. Did you know that, next to California, Yellowstone has more earthquakes than any other place in the U.S.? It averages 3,000 a year, although most are not felt because they are small. These earthquakes affect thermal activity - they change the earth beneath, causing water passages to shift, become blocked, or lead to new locations. The earth beneath one's feet, especially in Yellowstone, is quite literally dynamic and constantly changing. When a sign says "unstable earth", believe it!
Old Faithful isn't the only geyser in the park, of course, nor is it the largest. But it is the most predictable, which makes it, perhaps, the most satisfying for visitors. I found a few others that I really enjoyed. My favorite is one called Steamboat Geyser, which is perhaps the most unpredictable in the park. When I heard it was unpredictable, I assumed it erupted perhaps once or twice a week, but never on a schedule. Imagine my surprise when we arrived to view it, and found a sign that says it could erupt in 4 days or in 50 years! It's last major eruption was in May of 2005. It seems to me to be a playful geyser. While we were there it had several small eruptions, nothing major, and with no discernable pattern. (Lee's photos, the two below)
Now here is the other clincher - this geyser is the highest when it finally decides to go full force, forcing water up to 300 feet high, twice as high as Old Faithful. I would like to see it someday, but I don't want to be too close when it happens. Rangers know when it is getting ready to explode, because the hot spring a couple of hundred yards below it, normally active, starts to drain until empty. I imagine the rangers clear the area when this happens.
What I personally love most about the park are the colors. Because of the thermal and volcanic activity, rock and soil come in a variety of colors, ranging from red and pink to yellow, orange, and black. Even road cuts are splendidly colored! The larger hot springs have stunning turqoise centers, which really set off the warmer colors around them. In the photographs below, you will find many closeups of all of those exquisite colors, because I enjoy them so much I cannot stop myself from taking more photos. I am a slave to their beauty! :)These first photos are of the area surrounding the playful geyser above, Steamboat.
Some of the color comes from "bacteria mats", which are usually orange, yellow, or brown in color. These mats are made up of bacteria that thrive in hot water, some of the very few organisms that do:
When you add a turquoise hot spring to the mix, the results are stunning:
