While the story may not be true, the sentiment upon seeing the thermal features of Yellowstone country ring true for me. My first sighting of the Old Faithful geyser basin last year astounded me, making me wonder what the first explorers of this land must have thought. John Colter is widely thought to be the first white man to set eyes on Yellowstone, in 1808, but it wasn't until 1870 that "official" exploration parties, the most famous being the Washburn party, were deemed credible sources and hailed as the "discoverers" of Yellowstone. Previous explorers and mountain men were scoffed at, with no-one believing the thermal features we now have preserved in our beautiful National Park were real.
We had been waiting to head up to Yellowstone this spring for the bridge to open over Craig's Pass. The pass had been closed since last Labor Day to repair/rebuild the bridge. Without this route to Old Faithful Visitor's Center, it would be a much much longer drive for us coming up from the south, which is already an hour and a half drive. Once the pass opened June 11, we made plans with our friends Dan and Jonell to meet at Old Faithful and spend the day exploring the Upper Geyser Basin. They are working in West Yellowstone this summer, and it was pretty much a halfway meeting point.
We got an early start, and met at the Visitor's Center promptly at 9AM. It was already pretty busy there, which was going to be a recurring theme throughout the day. I have read in the local paper that visitors to Yellowstone National Park have increased over 26% through May 31 this year over last year. that's a huge increase! After finding Dan and Jonell, we noted the times for the "predictable" geysers to go off, and as we had about a half hour before Old Faithful was due to go off, we headed over to the Grizzly Grill to have a late breakfast. It wasn't very busy, and we all had our breakfast sandwiches in short order, while catching up with each other since we last met back at Disney in February. And then it was time to head over to our first viewing of Old Faithful, which turned out to be one of three times we saw it erupt this day.
Old Faithful's home is the Upper Geyser Basin, one of three large geyser basins along the Firehole River. This basin contains the majority of the world's active geysers, and we are fortunate enough to have it right here in the United States :-). There are only four other locations in the entire world that have large concentrations of hydrothermal features: Russia, Chile, New Zealand and Iceland. Our plan for the day was to thoroughly explore the Upper Geyser Basin, see as many of the "predicted" eruptions as possible, and then head up to Grand Prismatic Spring, another beautiful geologic feature of Yellowstone. And we were pretty successful at our task :-).
After our planning and strategizing session, we started out our adventure by climbing to the top of Observation Point for a birds-eye view of Old Faithful. this is a short but pretty steep climb to a rise of 160 feet with a grand view of both Old Faithful geyser and the historic Old Faithful Inn to the right. The inn was built in 1903-4 with local logs and stone, and is considered the largest log structure in the world.In 1987 it was designated as a National Historic Landmark.
We had a little while to go before the next "estimated" eruption time for Castle Geyser, so we hiked through the forest to Solitary Geyser. This pretty geyser sits off by itself and doesn't receive too many visitors, being off the beaten path. But we like it :-).
I like the close-up view of the ledges at the rim of the geyser pools. Solitary geyser has pretty high temperatures, preventing most bacterial growth and resulting in such exceptionally clear blue water. It's a small geyser that erupts around every seven minutes or so.
As we hiked out of the Observation Point loop trail to Castle Geyser, we saw many different types of hydrothermal features. This is a small un-named pool that is cooler, leader to a darker color and high bacterial growth.
We crossed over the Firehole River, after stopping to watch..
Spasmodic Geyser bubble away.
We arrived at Castle Geyser within it's "eruption window" time, and patiently waited.
Our patience was rewarded when it erupted.
There are three ingredients needed for these thermal features. Yellowstone, being a still active volcano, has had three major eruptions in the past 2.1 million years. The molten rock, or magma, may be as close as 3-8 miles underground, and provides the first ingredient, heat. Rain and snow provide the second ingredient, water, which seeps down several thousand feet below the surface where it is heated. Underground cracks form the third ingredient, a natural plumbing system. Hot water rises through the plumbing to produce hot springs and geysers.
We watched Castle Geyser for about 15 minutes, with the plumes of water shooting high in the sky and rivers running over the edge of the cone. This cone is thousands of years old and rests upon even older platforms of stone. Together they form one of the largest sinter formations in the world. Sinter is formed when the hot water that has erupted runs down the cone and cools, leaving behind a thin deposit called siliceous sinter, primarily composed of silicon dioxide (the same material found in glass).
We were still marveling at Castle Geyser, believing we had time to get to Grand Geyser before its predicted time window, when we heard shouting from that area. We turned and saw Grand Geyser spouting away! We quickly made our way across the bridge and boardwalks, along with plenty of other folks, and got our first look at the eruption of Grand Geyser.
Grand Geyser is a classic fountain geyser, which erupts in powerful bursts rather than a short steady column like Old Faithful. Grand Geyser is the world's tallest predictable geyser reaching heights of 180 feet or more, and the eruption can last from 9-12 minutes. Unlike Castle Geyser, which releases billows of steam for 30 minutes or more after an eruption, Grand Geyser stops abruptly with no steam. It can then take between 7 and 15 hours before erupting again.
A second, smaller geyser, Turban Geyser, started going off at the same time. Turban is the stream of water shooting off to the left of Grand Geyser.
So, what makes a geyser erupt??
Geysers are hot springs with constrictions in their plumbing, usually near the surface, that prevent water from circulating freely to the surface where heat would escape. The deepest circulating water can exceed the surface boiling point (199°F/93°C). Surrounding pressure also increases with depth, much as it does with depth in the ocean. Increased pressure exerted by the enormous weight of the overlying water prevents the water from boiling. As the water rises, steam forms. Bubbling upward, the steam expands as it nears the top of the water column. At a critical point, the confined bubbles actually lift the water above, causing the geyser to splash or overflow. This decreases pressure on the system, and violent boiling results. Tremendous amounts of steam force water out of the vent, and an eruption begins. Water is expelled faster than it can enter the geyser's plumbing system, and the heat and pressure gradually decrease. The eruption stops when the water reservoir is depleted or when the system cools. -National Park Service website
While Grand Geyser was erupting, off in the distance we could see Daisy Geyser erupting.
This picture is actually from last year, I wasn't close enough to get a good picture of Daisy. But so far we were doing pretty good...four out of the five predictable geysers erupted while we were there! We had a while before Riverside geyser was supposed to go off, so we headed down the trail to see more.
This interesting area is called the Grotto, and bubbles a lot and occasionally splashes up to 15 feet.
This is a pool in the Chain of Lakes area that shows some really cool bacterial mat color and stunted, dead trees along its edge.
We made it to the famous Morning Glory Pool, named for its remarkable likeness to the flower. This pool has long been a victim of vandalism, with tons of coins, rocks, trash and logs having been thrown into the pool. Much of this debris has become embedded into the sides and vent of the spring, reducing water circulation and the temperature of the water. The cooler temperatures allow the orange and yellow bacteria to thrive in this spring.
As we turned back to head towards the Firehole River and hopefully catch our last geyser eruption...yes, you guessed it!
Another premature eruption! We quickly made our way down to the river's edge.
Riverside Geyser will erupt for up to 20 minutes, with a graceful arch of water over the river up to 75 feet high. We did see this one last year, after waiting an hour and a half for a delayed eruption, and it finally went off as we started to leave the area because of an impending thunderstorm. This day was much better ;-).
We started our trek back to the Visitor's center. This is Heart Spring, with a beautiful clear blue water pool and icy white edges.
Dan and Jonell stopped for our third viewing of Old Faithful for the day.
Our last interesting geyser is called Anemone Geyser. It looked pretty empty and dry when we walked up to it...
But after waiting a few minutes, the pool area filled, overflowed and then started bubbling. Suddenly a 6 foot high stream of water bursts out of the center for about a minute.
The eruption stops abruptly, and the water drains down the center with gurgling sounds. It looks completely dry again. The cycle repeats every 7-10 minutes. It was really cool.
By now our step counter showed we had done over 28,000 steps, about 10 miles!! Oh my! Time for some early dinner. The cafeteria at the Lodge is pretty good, and we headed there for a bite to eat and rest our feet for a little while. Then it was back to the cars, and we headed for a last short walk to view Grand Prismatic Spring in Midway Geyser Basin.
The best way to get a picture of this 370 foot diameter spring is to climb the ridge behind it to get a birds-eye view. The park frowns upon this as there is no official trail up there, and the number of dead lodgepole pines are somewhat of a falling hazard. Be that as it may, many people still make the hike up there, but we were already pretty beat from the mileage we had already done, plus the steam coming off of the spring was quite intense with the wind blowing.
Prismatic means brilliantly colored, and we can see how the spring got its name. I have not enhanced the colors at all in these pictures. The intense blue in the center of the spring is due to sunlight being scattered by fine particles suspended in the water. The water in the center is superheated, reaching about 189 degrees Farenheit. This heat prevents much from living there, causing the clear water. As the water spreads and cools, it creates concentric circles of varying temperatures. Each ring creates a different environment, allowing different types of thermophiles ( heat loving microorganisms) to inhabit each ring. Different types of these microbes have different colors, and give the rainbow effect to this hot spring.
The spring was officially first described and named by the Hayden Expedition in 1871, the first federally funded exploration of the lands that would become Yellowstone. The expedition's leader, Ferdinand Hayden, wrote "Nothing ever conceived by human art could equal the peculiar vividness and delicacy of color of these remarkable prismatic springs. Life becomes a privilege and a blessing after one has seen and thoroughly felt these incomparable types of nature's cunning skill."
Midway Basin is also home to Excelsior Geyser Crater, once the largest geyser in the world. Its last known eruption were in 1985, and it is now a productive thermal spring, discharging 4050 gallons per minute.
Our day finally ended, with a little over 11 miles covered. Feet tired, but senses exhilarated by the beautiful and unique natural features we had seen. We said our fond farewells to Dan and Jonell as they headed west to West Yellowstone and we turned south back to the Tetons. I'm sure we will see them again soon, there is much more territory to explore. In the meantime, I hope you enjoyed this tour of the most famous geyser basin in the world, and stay tuned; coming up is more adventure for us, with white water rafting, lectures and a visit to a horse whisper on the agenda!