Part of Yellowstone National Park’s Norris Geyser Basin area, the Back Basin is a more heavily wooded section of land filled with geothermal features spread throughout. Here you'll see a land of extremes... the tallest, but infrequent geyser, geysers that erupt continuously, springs that have been damaged by man, new geysers, old geysers, deep ones, colorful ones, and geysers that have exploded.
Take a walk on the 1.5-mile boardwalk and dirt trail that surrounds this part of the basin to see extreme geysers packed into this small area of Yellowstone.
The Vixen Geyser is known for its temperamental, spit-fire disposition. In fact, that’s why Yellowstone National Park’s second superintendent P.W. Norris named this feature “vixen.” The geyser’s temperature rises to 195°F, yet it’s eruption schedule is erratic to say the least. Intervals can last from minutes to hours; its eruption duration can go for seconds to 50 minutes; and the height of its stream can soar anywhere between 5 and 30 feet. Researchers have noted two “typical” kinds of eruptions. One displays minor activity every few seconds with occasional splashing and spouting up to 15 feet high mixed in. Major eruptions are rare and unpredictable, but when they do occur they can last up to an hour with water shooting up to 30 feet. After either type of eruption, the crater drains, leaving a gurgling sound in its wake. Vixen erupts from a round, cylindrical vent stained a pinkish color by iron oxides deposited with silica.
The Porkchop Geyser is relatively new as far as geysers go. It was a rather quiet, erratic geyser until 1985 with occasional eruptions between 15 and 20 feet high. In 1985 though, it began to erupt continuously spouting 30 feet high from its 3-inch diameter vent. The burst was especially surprising because of its 100°F temperature, which is well below boiling. Also, the water was full of silica. The geyser’s spray built up into a large ice cone nearly 8 feet high. It was draped with translucent silica gel. Then, on September 5, 1989 in full view of visitors, Porkchop exploded. Rock and debris were launched up to 220 feet away. Now it’s only a bubbling, seething pool with temperatures reaching between 98 and 162°F and a depth of 2.5 feet. The geyser measures 13x18 feet and was named in 1961 by geologist Don White because of its porkchop-shaped crater.
Cistern Spring is an example of living color. It’s brown, orange and green hues come from collections of algae and bacteria. These hardy species require an environment with varying temperatures, but all are able to thrive, rather incredibly, at temperatures near, at or above boiling.
The Echinus Geyser is an especially acidic geyser surrounded by millions of spine-shaped deposits. In fact “echinus” refers to a genus of sea urchins, which are rather spiky creatures themselves. When the Echinus Geyser erupts, it sprays out a mixture of iron, arsenic, manganese and aluminum, which helps to build the rust-colored sinter spines. The geyser fluctuates between periods of activity and dormancy. Its last bout of frequent eruptions occurred in the 1990s.
With bluish-colored water, Crater Spring joins the host of geothermal features in the Back Basin. Look for its steaming, gurgling mouth just past Echinus Geyser.
Twenty-seven feet deep and lined all the way down with sulfur, Emerald Spring boasts a vibrant green coloring. That emerald color comes from a mixture of the yellow sulfur with the pool’s reflected blue.
Steamboat & Puff 'N Stuff Geysers
Steamboat Geyser (above) is the world’s tallest active geyser. Its major eruptions are unpredictable and infrequent, but when it blows its top, its jet shoots more than 300 feet in the air. More frequent minor eruptions rise 10-40 feet. The last major eruption occurred on July 31, 2013.
In contrast, the Puff ‘N Stuff Geyser (below) is a very small geothermal feature. It’s in constant eruption, but the spray goes only a few feet.
Minute Geyser - Damaged by Man
Minute Geyser stands as a lesson learned the hard way. Although it once erupted every 60 seconds 40-50 feet in the air, now its eruptions are irregular. What happened? Early visitors used to throw rocks into Minute Geyser’s larger west vent, clogging the spout nearly irreparably. If the rocks were to be removed, it would require heavy equipment that would lead to other damage.