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What is a geyser? -

A geyser is a vent in the Earth's surface that periodically ejects a column of hot water and steam.

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How does a geyser work? -

Geysers result from the heating of groundwater by shallow bodies of molten rock called magma.

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Natural plumbing system -

For a geyser to work there must be heat, water, and a "plumbing system," i.e. a tube-like hole in the Earth's surface that runs deep into the crust.

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Reaching boiling point -

The magma heats the water in the tube. Over time, this water gets super hot and gradually begins to boil.

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Formation of steam or gas -

The boiling water begins to steam, or turns to gas. As steam or gas bubbles begin to form in the tube, hot water spills from the vent of the geyser, and the pressure is lowered on the water column below.

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Onwards and upwards -

Water at depth then exceeds its boiling point (212°F, or 100°C) and can reach a scalding 285°F, or 140°C, before it flashes into steam. The steam begins to jet to the surface.

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Breaking the surface -

This forces more water from the tube and lowers the pressure further. The water breaks the surface.

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The eruption -

Eventually the powerful jet of steam ejects the column of water above it. The water rushes through the tube and is propelled into the air.

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Chain reaction -

This chain reaction continues until the geyser exhausts its supply of boiling water, or until the temperature inside the geyser drops below boiling.

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Refueling process -

After the eruption, water slowly seeps back into the tube, effectively 'refueling' the vent. The process then starts all over again.

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Etymology -

The term geyser in English dates back to the late 18th century and is derived from Geysir, which is a well-known geyser in Iceland. Its name means "gusher," or "one who gushes."

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Geysir, Iceland -

Geysir, also known as "The Great Geysir," is located in Iceland's Haukadalur Valley on the slopes of Laugarfjall lava dome. It was the first geyser described in a printed source and the first known to modern Europeans.

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Iceland's geysers -

Amateur British scientist John Thomas Stanley made a celebrated voyage to the Faroe Islands and Iceland in 1789. His accounts of the hot springs and geysers at Haukadalur were published in 1791.

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First general reference -

The first general reference to these geothermal wonders, however, was made by the 12th-century Danish historian and author Saxo Grammaticus in Gesta Danorum.

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Largest geyser locale -

Geysers are rare natural wonders. The combination of water, heat, and fortuitous plumbing required to create them exists in few places on Earth. The largest geyser locale on the planet is Yellowstone National Park in the United States, home to 500 active geysers and arguably the most famous: Old Faithful.

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Old Faithful -

Old Faithful was named in 1870 for its highly predictable nature. It erupts about every 90 minutes, with more than one million eruptions having so far been recorded.

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Steamboat Geyser -

Old Faithful is not the tallest or largest in the park. That distinction belongs to Steamboat Geyser, in fact the tallest geyser in the world, capable of venting eruptions up to 400 feet (122 m) in height. It's so named because of its similarity to the jets of steamboats.

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Castle Geyser -

Other popular geysers in Yellowstone include Castle Geyser, one of the oldest in the park. Castle Geyser is estimated to be around 15,000 years old. Geophysicists know this because of the size of the cone. It takes thousands of years for such a large conical shape to form.

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Great Fountain Geyser -

Yellowstone's Great Fountain Geyser is another crowd-pleaser. It erupts every nine to 15 hours, with eruptions sometimes reaching over 220 feet (67 m).

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Riverside Geyser -

Riverside Geyser has one of the most picturesque settings of any geyser in Yellowstone.  As is Old Faithful, Riverside is one of the most predictable geysers in the park, its interval anywhere between five to seven hours.

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Grand Prismatic Spring -

Yellowstone's most spectacular hot spring is the Grand Prismatic Spring. It's also the park's largest. Hot springs are the most common hydrothermal features in Yellowstone. Restrictions in their plumbing prevents water from reaching the temperature needed to set off an eruption.

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Morning Glory Pool -

An anomaly is the Morning Glory Pool. On rare occasions, this hot spring has erupted, usually following an earthquake or other nearby seismic activity.

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Valley of Geysers, Russia -

The aptly named Valley of Geysers is located on the Kamchatka Peninsula, in Russia's far east. It is part of the Kronotsky Nature Reserve, a UNESCO World Heritage Site. In 2007, a massive mudflow inundated two thirds of the valley, severely damaging the environment and burying many of the geysers. UNESCO is still monitoring the area for any signs of renewed geothermal activity. Despite the catastrophe, the valley remains the second-largest geyser locale on Earth after Yellowstone.

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El Tatio, Chile -

The El Tatio geothermal field is the third-largest of its kind in the world, and the largest in the Southern Hemisphere. Located in the Andes Mountains of northern Chile, El Tatio contains more than 80 active geysers.

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Pohutu Geyser, New Zealand -

The spectacular geothermal area of Rotorua in New Zealand's North Island is celebrated for its bubbling mineral springs, burping mud pools, and the spectacular Whakarewarewa volcanic valley. The star attraction here is Pohutu Geyser.

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Lady Knox Geyser, New Zealand -

Lying north of Rotorua is the Waiotapu area of the Taupo Volcanic Zone. Stealing the show is the wonderfully named Lady Knox Geyser, named after Lady Constance Knox, the second daughter of Uchter Knox, 15th governor of New Zealand from 1897 to 1904. Eruptions produce a jet of water reaching up to 65 feet (20 m), and can last for over an hour.

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Andernach Geyser, Germany -

Geysers aren't always the product of geothermal activity. Cold-water geysers are those whose water spurts are propelled by CO₂ bubbles, instead of hot steam. The most famous example is Andernach Geyser in Germany. In November 2008, it was officially recorded by Guinness World Records as the highest cold-water geyser in the world, achieving 197 feet (60 m).

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Crystal Geyser, USA -

The United States has its own cold-water wonder, Crystal Geyser in Utah. Located approximately nine miles (14 km) downstream from the city of Green River, the geyser was created by an exploration well drilled in 1935 in attempt to locate oil.

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Enceladus -

While geysers rank as some of the most exciting geothermal phenomena on Earth, what about those beyond our planet? In 2023, NASA's James Webb Space Telescope captured Saturn's moon Enceladus blasting a plume of water 6,000 miles (9,656 km) high. The images led scientists to speculate whether life is lurking under the moon's icy shell.

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Triton -

Back in 1989, the Voyager 2 spacecraft photographed Triton's south polar terrain and recorded about 50 dark plumes on its surface, marking what may be ice volcanoes. Triton is the only moon of Neptune.

Sources: (National Park Service) (Water Shapes) (National Oceanic and Atmospheric Administration) (NASA Science) (Etymonline) 

See also: Mysterious moons of our solar system 

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