Halemaʻumaʻu Crater (six syllables: HAH-lay-MAH-oo-MAH-oo) is a pit crater within the much larger summit caldera of Kīlauea in Hawaii Volcanoes National Park. The roughly circular crater was 770 meters (2,530 ft) x 900 m (2,950 ft) before collapses that roughly doubled the size of the crater after May 3, 2018. Halemaʻumaʻu is home to Pele, goddess of fire and volcanoes, according to the traditions of Hawaiian religion. Halemaʻumaʻu means "house of the ʻāmaʻu fern".
Halemaʻumaʻu contained an active lava lake for much of the time before 1924, and was the site of several eruptions during the 20th century. The crater again contained an active lava lake between 2008 and 2018, usually fluctuating between 20 to 150 meters below Halemaʻumaʻu's crater floor, though at times the lava lake rose high enough to spill onto crater floor.
As new volcanic vents opened in lower Puna in May 2018, the level of the lava lake began to drop in early May 2018, eventually to the point where the lava lake was no longer visible. The subsidence of the lava lake was accompanied by a period of explosions, earthquakes, large clouds of ash and toxic gas, and finally a gradual collapse of the summit caldera around Halemaʻumaʻu Crater, resulting in the closure of the Hawaii Volcanoes National Park from May 10 to September 22, 2018. The collapse events ceased abruptly on August 2, 2018.
In the summer of 2019, for the first time in recorded history, a water pond appeared in Halemaʻumaʻu. The greenish pond has deepened and enlarged since first being observed.
Astonishment and awe for some moments rendered us mute, and like statues, we stood fixed to the spot, with our eyes riveted on the abyss below. Immediately before us yawned an immense gulf, in the form of a crescent, about two miles (3 km) in length, from north-east to south-west, nearly a mile in width, and apparently 800 feet (240 m) deep. The bottom was covered with lava, and the south-west and northern parts of it were one vast flood of burning matter, in a state of terrific ebullition, rolling to and fro its "fiery surge" and flaming billows.
It was like gazing at the sun at noon-day, except that the glare was not quite so white. At unequal distances all around the shores of the lake were nearly white-hot chimneys or hollow drums of lava, four or five feet high, and up through them were bursting gorgeous sprays of lava-gouts and gem spangles, some white, some red and some golden--a ceaseless bombardment, and one that fascinated the eye with its unapproachable splendor. The more distant jets, sparkling up through an intervening gossamer veil of vapor, seemed miles away; and the further the curving ranks of fiery fountains receded, the more fairy-like and beautiful they appeared.
The level of the lava lake varied over the decades. 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 366 m (1,200 ft) 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.
Crater eruption - 2008 to 2018
Beginning of the eruption
Halemaʻumaʻu was quiet for 25 years after the 1982 eruption, with eruptive activity at Kīlauea being focused on the volcano's east rift zone beginning in 1983. However, Hawaiian Volcano Observatory scientists observed a gradual increase in activity beginning in late 2007, including an increase in sulfur dioxide emissions and an increase in seismic tremor. By March 2018, these parameters were several times higher than normal.
Crater activity began to increase when between March 10 and March 14, 2008 gas began to vent from the east wall fumarole directly below the Crater Overlook. At 02:58 am HST on March 19, 2008, HVO personnel recorded seismic events, and sunrise revealed a 20–30 meter (65–100 foot) diameter hole blown in the side where the vent once was; the explosion scattered debris and spatter across 0.30 square kilometers (74 acres) and damaged the Crater Overlook. Pieces as large as 20 millimeters (1 in) were found on Crater Rim Drive while 0.3 m (1 ft) blocks hit the crater overlook area. This was the first explosive eruption of Halemaʻumaʻu Crater since 1924, and the first lava eruption from the crater since 1982. The new crater formed in the explosion was informally named "Overlook Crater" by Hawaiian Volcano Observatory staff.
Sulfur dioxide gas emissions increased rapidly at the beginning of the episode. On March 13, HVO recorded a rate of 2,000 tons/day, the highest rate since measurements began in 1979. A concentration of over 40 ppm on Crater Rim Drive was measured, prompting alerts and other public safety measures. Halemaʻumaʻu crater continued to intermittently emit high levels of volcanic gases, ash, spatter, Pele's Tears, and Pele's Hair until the second episode.
Another explosive event occurred during the night of April 9, 2008, which widened the Overlook Crater by an additional 5–10 meters (15–30 feet), ejected debris over some 60 m (200 ft) and further damaged the overlook as well as scientific monitoring instruments.
In response to the second episode, scientists and local government officials on April 9, 2008 ordered hundreds of people to evacuate from the Park and nearby villages because the sulfur dioxide concentration levels had reached a critical level and a hazardous vog plume extended downwind from the crater. The evacuation lasted two days.
On April 16, 2008, a third significant explosive event occurred at Halemaʻumaʻu, spreading ash and debris throughout the area. Subsequently, a second evacuation of the park and surrounding areas was ordered on April 23, 2008.
Activity continued through the next few months, with Halemaʻumaʻu continuing to emit a plume of ash and gases. A fourth explosive event occurred on August 1, 2008, and a fifth on August 27, 2008.
September 2008: Lava lake becomes visible
A Hawaii Volcano Observatory news release and images dated September 5, 2008 confirmed the first recorded images of a lava lake 130 feet below the lip of the Overlook Crater. The HVO had alluded to the presence of lava within the vent, including the sporadic ejecting of lava materials from the vent due to explosive episodes, but this gave officials the first opportunity to visually confirm that active lava was present. The report also noted that the lava could not be seen from observation points around the crater.
September 2008 to April 2018: Sustained lava lake
The lava lake within Halemaʻumaʻu's Overlook Crater vent was visible nearly continuous from March 2008 until May 2018. During the period, the Overlook Crater slowly enlarged. The height of the lava lake fluctuated. In May 2015, the lake rose high enough to spill onto the Halemaʻumaʻu crater floor for the first time, adding a layer of lava approximately 30 feet (9 m) thick to the crater floor.
For three years from 2015 to 2018 the lava lake level remained close to the rim, with a further minor overflow event in October 2016 and a significant one in April 2018 that covered a majority of the crater floor in new lava.
In April 2018, a significant series of overflows had reportedly covered most of the Halema'uma'u Crater floor with new lava.
April to July 2018: Drainage of lava lake and the collapse of the summit
On April 30, the Pu'u O'o crater on Kīlauea's east rift zone collapsed. Several days later, lava began to emerge from fissures on the lower east rift zone in Leilani Estates. On May 1, concurrent with the shift of activity on Kīlauea's east rift zone, the summit lava lake within Halemaʻumaʻu's Overlook Crater began to drop; the US Geological Survey's status update on the evening of May 6 reported that Halemaʻumaʻu‘s Overlook Crater lava lake had dropped by 722 feet (220 m) since April 30. By May 10, the lava lake was no longer visible. Geologists believed that the draining of the lava lake was driven by a steady withdrawal of magma from Kīlauea's summit to feed the eruption on the volcano's lower east rift zone. Several small explosive events occurred between May 16 and May 26, ejecting ash and small blocks within a few hundred meters of the vent. An explosion on May 17 created an ash plume that reached 30,000 feet above sea level.
Beginning near the end of May, the floor of Kīlauea Caldera around Halemaʻumaʻu began to subside in a series of 62 separate collapse events. At each collapse event the floor of the caldera dropped several meters and there was a magnitude 5.2 to 5.4 earthquake. Between each collapse event, an escalating swarm of earthquakes would occur. Notably, more than 700 earthquakes of a magnitude 4.0 or higher occurred each day during the collapse period. The collapse events enlarged and deepened Halemaʻumaʻu. The crater's volume increased from about 54-60 million cubic meters to 885 million cubic meters, and the depth of the crater increased by more than 500 meters. During the collapse, the former Halemaʻumaʻu overlook and its parking lot were lost when segments of the crater rim slumped into the crater. The summit collapse events ceased abruptly on August 2, 2018, two days before the eruptive activity on Kīlauea's east rift zone decreased significantly.
2019 water pond
In late July 2019 a greenish surface was reported at the bottom of the much-deepened crater. On August 1, observations proved the existence of a small water pond in Halemaʻumaʻu. Further observation in August showed the pond was rising, with a water temperature of about 160 degrees.  The pond is the first time in recorded history that liquid water has appeared in the crater.
White-tailed tropicbird is flying directly over the Halemaʻumaʻu vent, 2008
Time lapse video of Halemaʻumaʻu Crater, 2014
Time lapse video of the lava lake in Halemaʻumaʻu Crater, 2016
Time lapse video of Halemaʻumaʻu Crater, 2017
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- "Introduction to Kilauea Volcano, Hawai'i". Hawaiian Volcano Observatory. 13 March 2007. Retrieved 2008-04-23.
- Knabel, Sarah (2005-11-23). "Field Stop 12: Halema'uma'u Crater". Geography Capstone October 23, 2005. Archived from the original on December 11, 2012. Retrieved 2009-07-09.
- William Ellis (1823). "A journal of a tour around Hawaii, the largest of the Sandwich Islands". Crocker and Brewster, New York, republished 2004, Mutual Publishing, Honolulu. ISBN 1-56647-605-4. Cite journal requires
- Mark Twain (1872). "LXXV". Roughing It. David Widger.
- Coan, Titus (1882). Life in Hawaii. New York: Anson Randolph & Company.
- "The 1924 explosions of Kilauea". Hawaiian Volcano Observatory. May 1924. Retrieved 2008-04-25.
- "Summary of Historical Eruptions, 1750 - Present". Hawaiian Volcano Observatory. 18 April 2005. Retrieved 2008-04-23.
- "Chronology of Kīlauea's summit eruption, 2008 - 2018". Hawaiian Volcano Observatory. US Geological Survey. Retrieved 14 August 2019.
- "New gas vent in Halemaʻumaʻu crater doubles sulfur dioxide emission rates". Hawaii Volcano Observatory (HVO). HVO, USGS. March 14, 2008.
- "Archived copy". Archived from the original on 2008-03-28. Retrieved 2008-04-23.CS1 maint: archived copy as title (link)
- "Explosive eruption in Halema`uma`u Crater, Kilauea Volcano, is first since 1924". Hawaii Volcano Observatory (HVO). HVO, USGS. March 19, 2008.
- Dondoneau, Dave (March 19, 2008). "1st explosive eruption since 1924 reported at Kilauea". The Honolulu Advertiser. Gannett Corporation. Retrieved 2008-04-18.
- Dayton, Kevin (April 9, 2008). "Volcano park evacuated; Blanket of toxic vog drifts over Big Isle but most residents stay put". The Honolulu Advertiser. Gannett Corporation. Retrieved 2008-04-18.
- "Halemaʻumaʻu gas plume becomes ash-laden". Hawaii Volcano Observatory (HVO), USGS. March 24, 2008. Retrieved 2008-04-22.
- "Halema'uma'u Vent Explodes a Second Time". Hawaii Volcano Observatory (HVO), USGS. April 10, 2008. Retrieved 2008-04-22.
- "KITV News, April 23, 2008". Kitv.com. 2008-04-23. Retrieved 2013-12-27.
- "Sloshing lava lake viewed within Halema'uma'u vent". Hawaii Volcano Observatory (HVO), USGS. September 5, 2008. Retrieved 2008-09-06.
- Nace, Trevor (19 September 2016). "Incredible Photos Of Hawaii's Overflowing Lava Lake". Forbes. Retrieved 2016-11-28.
- Hansel, Jeff (18 October 2016). "Lava lake overflows into Halema'uma'u Crater". Hawaii Tribune-Herald. Retrieved 2016-11-28.
- "Summit lava lake still overflowing into crater". Star Advertiser. April 26, 2018. Retrieved 27 April 2018.
- Changes in the Kīlauea caldera from May 14 to July 19, 2018 (Planet Labs Inc.)
- "Overview of Kīlauea Volcano's 2018 lower East Rift Zone eruption and summit collapse" (PDF). US Geological Survey. Retrieved 14 August 2019.
- Neal, C. A.; Brantley, S. R.; Antolik, L.; Babb, J.L; Burgess, M.; Calles, K.; Cappos, M.; Chang, J. C.; Conway, S.; Desmither, L.; Dotray, P.; Elias, T.; Fukunaga, P.; Fuke, S.; Johanson, I. A.; Kamibayashi, K.; Kauahikaua, J.; Lee, R. L.; Pekalib, S.; Miklius, A.; Million, W.; Moniz, C. J.; Nadeau, P. A.; Okubo, P.; Parcheta, C.; Patrick, M. R.; Shiro, B.; Swanson, D. A.; Tollett, W.; Trusdell, F.; Younger, E. F.; Zoeller, M. H.; Montgomery-Brown, E. K.; Anderson, K. R.; Poland, M. P.; Ball, J. L.; Bard, J.; Coombs, M.; Dietterich, H. R.; Kern, C.; Thelen, W. A.; Cervelli, P. F.; Orr, T.; Houghton, B. F.; Gansecki, C.; Hazlett, R.; Lundgren, P.; Diefenbach, A. K.; Lerner, A. H.; Waite, G.; Kelly, P.; Clor, L.; Werner, C.; Mulliken, K.; Fisher, G.; Damby, D. "The 2018 rift eruption and summit collapse of Kīlauea Volcano" (PDF). Science. Retrieved 14 August 2019.