Haukadalur Valley, known as the Land of Boiling Waters, is a very active geothermal area in the southwest of Iceland. The valley is home to a multitude of mud pools, fumaroles and algal deposits. Walking trails lead visitors through steaming vents turquoise pools and glistening, multicoloured mud formations.
The area is most famous for its geysers, in particular one named Strokkur (meaning the churn), which erupts every four to eight minutes and spurts boiling water over 20 metres (66 feet) into the air.
Geysers are found in geologically active areas, in particular those near active volcanoes, and are quite a rare phenomenon due to the precise conditions that are required for them to form. There are only around 1,000 active geysers in the world.
Each geyser requires a regular supply of water to refill its reservoir, access to magma a few miles below to provide the necessary heat and a specific geological construction in order to build up the pressure necessary for eruption. Underground, the cone-shaped structure maintains pressure as the water heats, increasing the temperature of the water to well above the boiling point and ensuring a massive explosion once the pressure is relieved. Without this pressure, a heated reservoir would become a hot spring. When the water works its way to the surface, it releases the pressure, causing a sudden and massive boil-over. This ejects all of the water in the reservoir to the surface in a boiling plume.
Within the valley the Great Geysir, which has given its name to all such water spouts around the world, is also found. The Great Geysir started erupting in 1294, when a powerful earthquake shook the lowlands of Iceland and changed the geothermal area of Haukadalur Valley, and used to reach heights of around 60 metres (200 feet). For decades Geysir has been near dormant and in the 20th century eager tourists tried to force an explosion by tipping gravel and rubbish into its mouth. In 2000 it sprung back to life and continued to spout water into the air periodically over several weeks, during a period when earthquakes had briefly changed the subterranean pressure. Today it remains in a slumberous state.
- Information provided by Cruise and Maritime Voyages
- Information provided by tour guide on Cruise and Maritime Voyages excursion
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