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Halemaumau Crater is a pit crater located within the much larger summit caldera of Kīlauea in Hawaii Volcanoes National Park. The roughly circular crater floor is x and is below the floor of Kīlauea caldera. Halemaumau is home to Pele, goddess of fire and volcanoes, according to the traditions of Hawaiian mythology. The crater is currently active, containing a lava lake. From 2008, when the current vent inside Halemaumau crater first erupted, to April 2015, lava was present inside the vent fluctuating from 20 to 150 meters below the crater floor. On April 24, 2015 molten lava in the vent, known as the Overlook Crater, became directly visible for the first time from the Jaggar Museum overlook at the Hawaiian Volcano Observatory when the lava rose to an all-time high level since the Overlook Crater first opened.〔http://hawaiitribune-herald.com/news/local-news/lava-lake-hits-new-high〕〔http://hawaiitribune-herald.com/topnews/kilauea-lava-lake-now-visible〕 A few days later, on April 29, the lava started spilling over the rim of the Overlook Crater and onto the floor of Halemaumau Crater.〔http://hawaiitribune-herald.com/news/local-news/lava-lake-spills-over-rim〕 The lava lake has since receded back out of view.〔 April 24th Update〕 ==Early history== Early eruptions were only recorded by oral history. One large one in 1790 killed several people, and left footprints in hardened ash of some ancient Hawaiians killed by pyroclastic flows. William Ellis, an English missionary and amateur ethnographer and geologist, published the first description of Halemaumau as it appeared in 1823. In 1866 Mark Twain, an American humorist, satirist, lecturer and writer hiked to the Caldera floor. He wrote the following account of the lake of molten lava which he found there: Another missionary, Titus Coan, observed and wrote about eruptions in the 19th century. Geologist Thomas Jaggar opened an observatory in 1912, and the area became Hawaii Volcanoes National Park in 1916. The level of the lava lake varied over the decades and at times was only below the crater rim. In 1924, unusual explosive eruptions sent dust high into the atmosphere and doubled the diameter of the crater. Fractures allowed the lava lake to drain to the east until its surface was below the caldera floor. Subsequent eruptions have mostly refilled the crater. Most of the current crater floor was formed in 1974.〔 A 1982 eruption covered a small portion of the northeastern crater floor. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Halemaumau Crater」の詳細全文を読む スポンサード リンク
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