Geysers/hot springs, Yellowstone National Park
These two geothermal activities are interconnected. Cistern Spring is a gorgeous blue overflowing pool that deposit as much as a half inch of sinter – opaline silica – Old Faithful deposits that much in a century. The neighboring lodgepole pines show the problem of growing next to hot springs and geysers. Steamboat Geyser is the World’s tallest geyser shooting to more than 300 feet. The major eruptions are not very common and unpredictable. More common are minor eruptions boosting water to ten to forty feet in the air. Following a major eruption, the waters of the Cistern Spring drain.
You can return to the parking lot or extend your visit here in Norris to wander over to the Back Basin where more geothermal features await. Minute Geyser is here. It was named for its near constant eruptions. They are not so frequent now because trash people threw in has now clogged one of the main vents. Further on is the large crater of the Monarch Geyser on one side and the little Palpitator Spring on the other. You come to an intersection at Vixen Geyser from where you can venture farther into the Back Basin or cut the visit short turning towards the Veteran Geyser. Vixen has minor and major eruptions and the pink color around the cone is due to iron oxides. Veteran can be an active geyser, multi-vented, it can shoot water out at an angle up to 40 feet, but the geyser then will take a while off to regain its powers.
The main boardwalk path takes one through the middle of Porcelain Basin where you can get up close to the geothermal features – the bright colors are secondary to lime-green algae that love the hot acidic water. Orange cynobacteria add to the color giving a rusty look. Pinwheel Geyser dances a short ways from the walk. Further on the west edge of the loop you come across Crackling Lake, so called for the nearby little hot springs on the southern side of a small lake. Returning to where you started out from, steam roars from the Dark Cavern Geyser – the less frequent but even larger Ledge Geyser is off on its east side.
Norris is the hottest and most active of Yellowstone’s geothermal areas. There are two loop trails that take off from near the large parking lot. The one going to the north takes you through Porcelain Basin. It is well worth taking a side trail to the eastern edge past Congress Pool, first, and then you come out a wonderful overlook out over the multicolored basin. Steam vents hiss. Geysers gurgle. The smell of sulfur is in the air. Some of the geothermal features are here today and gone the next.
On the west side of the drive are boardwalks that take you out onto the east edge of Hot Lake. On the way there are more geysers -Steady Geyser – the largest constantly erupting geyser in the World with a height of two to fifteen emanating from one of two vents. The heated water – augmented by more geyser waters – steams in the cool mountain air. Breezes flit the steams off the cold surface of the nearby lake completing a surreal picture.
Driving further on, you pass Firehole Lake to a parking lot on its west side – on the other side of the road is the much larger Hot Lake. A couple of geysers can be found along a boardwalk going off to the east. You walk past Young Hopeful Geyser a constant erupter – a collection of several vents blowing water up to six feet though two feet is more the norm. Artesia Geyser is at the end of the boardwalk on the east side of the parking lot for Firehole Lake. Artesia is another perpetual geyser erupting out of two cones up to five feet in height.
Firehole Lake Road is a one-way road that takes off from the highway linking Old Faithful with Madison about midway along. It is just past the stop for the Midway Geyser Basin moving downriver from Old Faithful. The geothermal features along this road belong to the Lower Geyser Basin of which the most famous is probably the Fountain Paint Pots which are found along the main highway where this side road rejoins.
There are two particularly large geysers found along the way – Great Fountain Geyser and White Dome Geyser. Great Fountain shoots a couple times a day for about an hour reaching heights up to 100 to 200 feet. The geyser pool fills about an hour before an eruption begins. The White Dome Geyser erupts much more often but with less stature – the open orifice is only some 4 inches across as years of mineral laden spray has built up an impressive 20 foot high cone.
Algae are responsible for much of the magnificent colors seen in the hot pools. Blue-green algae can live in water up to 167 degrees F. As the water cools, the color changes to brown-orange. Algae tend to be winter-loving or summer-loving, as well, with the latter better able to cope with UV rays. The algae thrive in very acidic water – pH 0 to 3.5 – and can detoxify arsenic.
Hot springs are geysers without constrictions, while geysers are hot springs with constrictions. Earthquakes can certainly change things. Several features have gone from geysers to springs and back again. Avoca Springs used to be just a hot pool but the 1959 earthquake turned it ‘on’. Now, it is frequently spouting and churning in its puffy manner. Another such is Mustard Spring – there are two springs but only East Mustard active of the two since a 1983 trembler.
The geysers here in the Biscuit are small in stature, but they are fairly active. Jewell Geyser goes off every five to ten minutes, blowing up to ten feet in the air. It is thought to have an underground connection perhaps with the Sapphire Pool. Shell Geyser seems to be constantly on the boil though its eruptions are noted to be an hour or more in between. If you note the water level in a geyser filling and churning, you might hang out for the potential blast to come.
Biscuit Basin lies further down the Firehole River just before the Midway Geyser Basin. A short quarter mile trail crosses the river and loops around geysers, hot springs and pools. Trails continue on to Mystic Falls and even further, you can connect up to Fairy Falls and Midway Basin. Biscuit Basin is a very active geothermal area – it is actually still part of the Upper Geyser Basin - that could hotter after the 1959 earthquake. The basin is named for rock features on the Sapphire Pool which resembled biscuits. A few days after the earthquake, the pool waters erupted and many of the biscuits were blown off. The former geyser qualities ended many years ago though the water still churns at 200 degrees F. While longer does the pool erupt, it has regained its beautiful crystal blue colors.
Castle Geyser is the largest cone-type geyser in Yellowstone. Eruptions occur once a day or so but are unpredictable. Splashing waters can mean a major eruption is about to happen or only a minor affair. Major eruptions – which also tend to be loud - consist on average of a 20 minute water burst followed by 40 more minutes of steam. Water is shot upwards of 60-90 feet into the air. The geyser is very old. The twelve foot high cone has taken from 5000 to 15,000 years to build up and Castle’s cone sits atop an even larger formation from an earlier spring.
You cross the Firehole River just downstream from the Riverside Geyser – just past Grotto. A couple of small geysers bluster along the river bank – Mortar, Fan and Spiteful – as you pass. Another 50 yards takes you Morning Glory Pool. The colors are still glorious but nowhere near as in the past when deep blue reigned in the center. It is thought that the hot spring has changed due to an inordinate amount of trash that has been thrown by people into the pool over the years. But geothermal activity changes with time – helped no doubt by the trash – and colors, heat they change. Mammoth Hot Springs is an even better example of that.
This is one of the largest geysers in the World. Eruptions blast up to 300 feet high though normally 200 feet is what is normally experienced nowadays. The geyser’s base demonstrates the age of the geyser. Minerals build up an inch or so for each 100 years, thus Giant is thousands of years old. The geyser is closely grouped with several others – Bijou and Mastiff - along the Firehole River including the nearby Grotto Geyser which undermines the frequency with which Giant erupts.
Grotto gets its shape from coming up amongst a group of trees in which only the stumps were left as the minerals slowly caked over them. Eruptions get up to 40 feet and last anywhere from 20 minutes to almost an hour or much longer. The Park geyserologists did not have a prediction board out in front of this one, so we were pleasantly surprised to see it going off on our return walk to Morning Glory Pool further downstream. Next, to the Grotto on the west side is the medium sized Rocket Geyser which shoots up with vigor simultaneously – the two geysers are linked underground.