The sun’s out! What a change from the gray landscape and snowy conditions we’ve seen day after day in Yellowstone. Let’s head to the Upper Terrace at Mammoth Hot Springs for a winter hike around the loop called Upper Terrace Drive. During the summer season (April-early November), this road is cars only. When snow falls, it becomes the domain of folks on skis and snowshoes.
The Mammoth upper and lower terraces form a massive hill of travertine. Travertine is the result of thermal (HOT mineral-laden) water rising through limestone. The water carries large amounts of dissolved limestone (calcium carbonate) as it races to the surface. Upon reaching the surface, carbon dioxide is released depositing the calcium carbonate which forms travertine, the chalky white mineral that forms the rock of the travertine terraces. Travertine formations grow rapidly due to the “soft” nature of limestone. They also change quickly as we will see along the trail. One fascinating fact that continues to amaze me is that all the extremely hot water creating this entire travertine area comes through a fault line from Norris Geyser Basin about 20 miles south. That is some hot-water pipeline. So my friend, strap on those snowshoes and let’s go!
At the beginning of the loop we look north seeing the Absaroka Mountains which from here run north about 55 miles. The entire range is about 150 miles long running through Montana and Wyoming. Forming the eastern boundary of Yellowstone, this sub-range of the Rocky Mountains is 75 miles at its widest point. There are 46 peaks in the range over 12,000 feet with the highest peak being Francs Peak (Wyoming) standing at 13,153 feet. Absaroka is named after the Crow Indians, being the Indian name for Crow.
Let’s head out with my friend who is getting a head start. Looking northwest we see the Gallatin Range. From the north boundary of Yellowstone, the range continues south about 15 miles. The entire range is about 75 miles long and is the southeastern edge of my hometown of Bozeman, Montana. The range averages about 20 miles wide with the highest peak, Electric Peak (10,969 feet), found in northwestern Yellowstone near Gardiner, Montana.
To our left is Glen Spring. This active spring is one that has grown quickly. Remember though, we are talking rapid growth in geologic terms. Growing a foot or two in a few years or changing within two to five years is pretty rapid for rock.
In January of 2013 the cone at the top was much shorter and the massive run off, particularly to the right, was almost nonexistent.
Rocky Mountain juniper (Juniperus scopulorum) is the tree found among the thermal features here. The scientific name, scopulorum, means juniper of the rocks. Although sometimes called Rocky Mountain red cedar, junipers are a completely separate species, a member of the cypress family (Cupressaceae), where cedars are part of the pine family (Pinaceae). True cedars are only native to the western Himalayas and the Mediterranean region, making it obvious we are not looking at cedars. A very interesting fact is that junipers and redwoods are both in the cypress family. Redwoods include the tallest living trees on earth reaching 380 feet high and 30 feet in diameter where junipers don’t often reach 40 feet.
Junipers can be shrubs or trees reaching a maximum height of about 38 feet. The trunk can become twisted and gnarled with age, but no one seems to know why that happens. Could wind be a factor? It does get windy up here, so perhaps. The fruit are blue berry-like seeds and can cover some of the trees. A fascinating fact about these junipers is that many of the trees, particularly those taller with lots of new growth at their trunks, are known to be at least 1,000 years old! Somehow I just know I wouldn’t look this good at 1,000!
There’s the boardwalk that takes you to Canary Spring which flows over the front of the massive travertine hill we see from the lower road. As we discussed, thermal features tend to come and go at Mammoth, but Canary Spring has been active for quite a long time.
There’s the very top of Canary Spring with steam from the flowing water.
Let’s head uphill for a great view of the Mammoth Hot Springs community.
About 500 feet below we see the old Fort Yellowstone buildings with red roofs and the cream-colored buildings that include dining areas, employee facilities, and the Mammoth Hotel now in renovation mode until 2018 (black roof to left).
Look there, behind the trees on the right. That’s Narrow Gauge Terrace. Travertine terraces that are white are new or newer as well as active formations. As they age and over time become inactive, they turn darker gray. You can see these terraces are cracked and gray, but there’s a secret here and the hint is the steam between the two rock formations. We have a bit of a walk, but I’ll show you later.
On the rock faces that come down off Narrow Gauge we can see the formations that look like flowing rock. That’s exactly what they were when active with flowing thermal water evaporating leaving the travertine.
I always love the “rock pillows” formed by snow. Although Mammoth has one of the lowest elevations in Yellowstone, they had some impressive snow amounts this year by Mammoth standards. See the orange lichen on the center rock?
Oh my! As clouds begin to gather, the sun is creating a bow. I’ve seen sunbows a few times in Yellowstone, but this one is massive. A sunbow can actually be a circle around the sun or spread very far from side to side only. It is all about the sun shining through vapor or mist in the air. What a treat!
Peeking through the trees a bit further up the trail.
Well here we are. A short walk through the woods to the Howard Eaton Trail then north a bit for the surprise. This back side of Narrow Gauge Terrace is alive and well! Bright white travertine and the colors from the thermophilic algae (blue-greens also called cyanobacteria) and other thermophiles (heat-loving microorganisms) tell us this terrace is alive and well. The different colors represent different species of thermophiles that thrive in different water temperatures. We must come back after the snow melts so see the grand glory of this formation.
Back to our loop trail, we are heading up to an iconic feature loved by many. But wait . . .
. . . look up there. We are not the only ones walking the Howard Eaton Trail.
All along this part of the trail we parallel New Highland Terrace, formed in a forested area in the 1950’s and becoming inactive in the 1980’s. However, as with much of Mammoth, occasionally it comes to life within one area or another. See the teeth-like formation at the top of the terrace? We can see “teeth” forming below flowing hot springs in many places on Mammoth’s travertine terraces.
Here we are at the beloved formation. Orange Spring Mound at the sharp turn in the trail and the sight many come to see and photograph. The spring, at the front of the formation, is cooler and slower flowing resulting in more orange coloring, but seasonal changes in water flow rate and the amount of sunlight changes the colors that are prevalent. The colors are, of course, the types of thermophiles that live in the water. This is a slow-growing feature currently about 48 feet long and 20 feet wide.
Time to move on and up, but we have a sharp drop ahead as we’ll be starting our downhill walk to the car. The snow is deeper than it looks so thankfully we’re wearing our snowshoes. If we had simply worn our boots, we would be breaking through–called postholing–on a regular basis. Breaking through the snow straight down until enough snow packs to hold our weight. Depending on the density of the snow, that could be up to our waist or higher! Believe me, it is a tiring, struggling, miserable hike, sinking to your knees or higher with every step. Huff and puff! However, we’ll be fine on top of the snow with our snowshoes.
We are looking north again to the Absaroka Mountains (it is a loop after all). One thing I love about this area are the amazing dead trees that look like Halloween pictures. The trees died because of too much mineral-laden water as their water source and/or being surrounded by travertine cutting off the water supply all together. However, these trees can stand dead like this for hundreds of years. Pretty amazing.
As we start downhill, we see Aphrodite Terrace. When I first started visiting this area in 2013, this terrace was completely inactive. It is pretty incredible now and in warmer months the stark white terraces are filled with beautiful baby-blue water. We’ll come back to see that in June.
This is another feature that appears more inactive than not, White Elephant Back Terrace. Can you see why it is called white elephant back? The spine, the head and ears at the end of the feature. Well, it’s a reach, but maybe if you squint you’ll see it 😉
More and more clouds are coming in as we head down to the last feature. With no wind it has been a delightfully toasty hike. I think we got a little color in our cheeks from the sun too.
Another snow pillow with lots of similar “friends” in the area. This rock is covered with mostly green and black lichens.
Angel Terrace is the last feature on our loop. This feature became totally inactive within a few months about two years ago when Aphrodite Terrace became very active. Are these events related? You know, even the geologist experts have a hard time determining relationships. Apparently the underground piping is just too complex to always be able to figure out relationships. However, Angel Terrace is getting some color back which tells us what? Yup, becoming active. Well, OK, the steam is a bit of give away too.
This has been great fun. We finally had some sun not to mention the amazing, unique thermal formations. Glad you came along with us today!
Until next time, explore the wonders where you live . . .