Yellowstone's Castle Geyser

Photographer: Stu Witmer
Summary Author: Stu Witmer

For about 2 million years, the Yellowstone Plateau Volcanic Field (YPVF) has been home to extensive volcanic activity. Yellowstone National Park sits on top of a supervolcano's gigantic pool of magma that last erupted about 640,000 years ago.

Castle Geyser (seen here) is part of one of the largest sinter formations in the world. The structure was built in four or five stages over about a thousand years. When the Washburn Expedition surveyed the area in 1870, members of the party thought that the tall geyserite cone resembled a castle turret and gave it the name it has today.

"Geyser" is an Icelandic word for a vent in the Earth’s surface that periodically ejects hot water and steam. A typical geyser eruption begins when surface water seeps down into the earth where it is heated by a magma chamber. When the water gets hot enough, it boils over and comes blasting out any available vent.

Castle Geyser has both major and minor eruptions. Major eruptions occur every 10-12 hours and can last for an hour generally starting with a splash rocketing skyward as high as 100 feet. After about 10-20 minutes, the eruption ends and a loud steam phase begin and may continue for hours. Minor eruptions, on the other hand, are just a few minutes of water without any steam. When these happen, the next major eruption cannot be predicted.

 

Castle Geyser, Yellowstone National Park Coordinates: 44.4637, -110.8366

Related Links:
Yellowstone National Park from Space
Iceland's Strokkur Geyser