Lava bench

A lava bench is a volcanic landform with a horizontal surface raised above the level of the surrounding area. They are created when molten lava travels away from a volcanic vent and expands an old shoreline.[1] This is the process that creates new land in the ocean that life can eventually grow on. The Hawaiian islands are an example of land that was formed this way, and the Big Island is currently still expanding due to lava benches.[2] The Kilauea Volcano releases lava that flows down the slope of the volcano and eventually encounters the ocean; this lava flow hardens when it comes into contact with the significantly cooler water of the ocean and forms an unstable lava bench. Eventually, when the material beneath the lava bench stabilizes, it become stable land that has been added to the island. If a newly formed lava bench rests on sediments, it may pose hazards due to its extremely unstable structure.[2] Oftentimes, these benches are so unstable that they collapse into the sea, exposing the water to the hot lava on the interior of the bench and releasing acres of land into the ocean.[2] When the hot lava hits the water, violent explosions of steam can shoot large rocks and molten lava up to 300 feet inland.[1] These collapses are extremely dangerous because they can happen without warning, and anyone or anything on the bench will be caught in the collapse. For safety, people are advised not to walk on lava benches because of their unstable nature, and they must maintain a safe distance from the lava bench.[3]

References

  1. 1 2 Observatory, HVO, Hawaiian Volcano. "Lava bench is no boardwalk". hvo.wr.usgs.gov. Retrieved 2016-10-26.
  2. 1 2 3 "Volcanology photoglossary: explanation of volcanologic terms". www.volcanodiscovery.com. Retrieved 2016-10-26.
  3. Advertiser, Final. "Big Island gets smaller as lava bench breaks off." Honolulu Advertiser, The (HI) 04 Aug. 2006: NewsBank. Web. 26 Oct. 2016.

External links


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