| A geyser is a spring that intermittently ejects hot water and steam. Geysers are normally located near active volcanic areas, but the hydrogeological conditions that result in geysers are rare on Earth. A geyser forms when surface water seeps through porous rocks, till it contacts rocks heated by magma. The water is then heated till it boils and the hot and pressurized water rises and is then ejected out of the geyser's surface vent, emptying a reservoir. Once a geyser has ejected, the reservoir needs to refill before it can erupt again, giving rise to the intermitted character of the hydrothermal explosions. |
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Geysir and Litli Geysir. Haukadalur, Iceland; 16 & 23 July 2014. |
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Eruption of Strokkur. Haukadalur, Iceland; 16 July 2014. |
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Yellowstone (Wyoming), USA; 16 August 2017. |
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Yellowstone (Wyoming), USA; 22 August 2017. Giant geyser (left) and Grotto geyser (right). |
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Yellowstone (Wyoming), USA; 22 August 2017. Great fountain geyser. |
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Yellowstone (Wyoming), USA; 22 August 2017. Artemisia geyser. |
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Yellowstone (Wyoming), USA; 18 August 2017. Lone star geyser. |
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Yellowstone (Wyoming), USA; 16 August 2017. Old faithful geyser. |
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Yellowstone (Wyoming), USA; 22 August 2017. White dome star geyser. |