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Eruption History of Kilauea Volcano, Hawai’i
By USGS
When Kilauea began to form is not known, but various estimates are 300,000-600,000 years ago. The volcano has been active ever since, with no prolonged periods of quiescence known. Geologic studies of surface exposures, and examination of drillhole samples, show that Kilauea is made mostly of lava flows, locally interbedded with deposits of explosive eruptions. Probably what we have seen happen in the past 200 years is a good guide to what has happened ever since Kilauea emerged from the sea as an island perhaps 50,000-100,000 years ago.
Lava Erupts from Kilauea’s Summit and Rift Zones
Throughout its history Kilauea has erupted from three main areas, its summit and two rift zones. Geologists debate whether Kilauea has always had a caldera at the summit or whether it is a relatively recent feature of the past few thousand years. It seems most likely that the caldera has come and gone throughout the life of Kilauea.
The summit of the volcano is high because eruptions are more frequent there than at any other single location on the volcano. However, more eruptions actually occur on the long rift zones than in the summit area, but they are not localized, instead constructing ridges of lower elevation than the summit. Eruptions along the east and southwest rift zones have build ridges reaching outward from the summit some 125 km and 35 km, respectively.
Most eruptions are relatively gentle, sending lava flows downslope from fountains a few meters to a few hundred meters high. Over and over again these eruptions occur, gradually building up the volcano and giving it a gentle, shield-like form. Every few decades to centuries, however, powerful explosions spread ejecta across the landscape. Such explosions can be lethal, as the one in 1790 that killed scores of people in a war party near the summit of Kilauea. Such explosions can take place from either the summit or the upper rift zones.
Future of Kilauea
The foreseeable future of Kilauea looks much like the past.
Continued effusive eruptions will fill the caldera, heighten the summit, and build the rift zones—over and over and over again. Sporadic explosions will cause destruction but hopefully not loss of life. We cannot tell how much larger Kilauea will grow or when it will stop, but it will surely continue to erupt through the rest of human history.
Kilauea—Perhaps the World’s most active Volcano
Kilauea is the youngest and southeastern most volcano on the Big Island of Hawai‘i. Topographically Kilauea appears as only a bulge on the southeastern flank of Mauna Loa, and so for many years Kilauea was thought to be a mere satellite of its giant neighbor, not a separate volcano. However, research over the past few decades shows clearly that Kilauea has its own magma-plumbing system, extending to the surface from more than 60 km deep in the earth.
In fact, the summit of Kilauea lies on a curving line of volcanoes that includes Mauna Kea and Kohala and excludes Mauna Loa. In other words, Kilauea is to Mauna Kea as Lo‘ihi is to Mauna Loa. Hawaiians used the word Kilauea only for the summit caldera, but earth scientists and, over time, popular usage have extended the name to include the entire volcano.
15 May 2000The eruption of Kilauea Volcano that began in 1983 continues at the cinder-and-spatter cone of Pu‘u ‘O‘o (high point on skyline). Lava erupting from the cone flows through a tube system down Pulama pali about 11 km to the sea (lower left). Map of Kilauea, including location of Pu‘u ‘O‘o Sketch showing magma reservoir & active lava-tube system
Kilauea is the home of Pele, the Hawaiian volcano goddess. Hawaiian chants and oral traditions tell in veiled form of many eruptions fomented by an angry Pele before the first European, the missionary Rev. William Ellis, saw the summit in 1823. The caldera was the site of nearly continuous activity during the 19th century and the early part of this century. Since 1952 there have been 34 eruptions, and since January 1983 eruptive activity has been continuous along the east rift zone. All told, Kilauea ranks among the world’s most active volcanoes and may even top the list.
Eruption Update | Eruption Summary | Hazards | History |
Kilauea Facts
Map of the Island of Hawai‘i Location
19.425 N 155.292 W
Elev. Above Sea Level
1,277 m
4,190 ft
Area
1,430 km2
552 mi2
(13.7% of Hawai‘i)
Volume
25,000-35,000 km3
6,000-8,500 mi3
Hawaiian Meaning
The Hawaiian name “Kilauea” means “spewing” or “much spreading,”
apparently in reference to the lava flows that it erupts.
Most Recent Eruption
Continuous since January 3, 1983
Number of Historical Eruptions
61, not counting the continuous lava-lake activity in Halema‘uma‘u crater
Summit Caldera
The caldera itself has no Hawaiian name other than Kilauea but houses the
famous crater, Halema‘uma‘u; “hale” is a house, “ma‘uma‘u” a type of fern. Kamapua‘a, a jilted suitor of Pele, is said to have built a house of ferns over Halema‘uma‘u to keep Pele from escaping her home and causing eruptions. The ploy failed.
Dimension: 6 x 6 km (outermost faults), 3 x 5 km (main depression)
Depth: 165 m deep
Age: probably several incremental collapses 500-210 years ago
Oldest Dated Rocks
23,000 years old
Estimated Age of Earliest Subaerial Eruptions
50,000-100,000 years
Estimated Age of First Eruption of Kilauea
300,000-600,000 years before present
Hawaiian Volcano Stage
Shield-forming stage
Summary of Pu‘u‘O‘o - Kupaianaha Eruption, Kilauea Volcano, Hawai‘i
Summary of the Pu‘u ‘O‘o-Kupaianaha Eruption, 1983-present
Pu‘u‘O‘o cone
Kupaianaha shield
The Pu‘u ‘O‘o-Kupaianaha eruption of Kilauea, now in its eighteenth
year and 55th eruptive episode, ranks as the most voluminous outpouring of lava on the volcano’s east rift zone in the past five centuries. By January 2000, 1.9 km3 of lava had covered 102 km2 and added 205 hectares to Kilauea’s southern shore. In the process, lava flows destroyed 181 houses and resurfaced 13 km of highway with as much as 25 m of lava.
Beginning in 1983, a series of short-lived lava fountains built the massive cinder-and-spatter cone of Pu‘u‘ O‘o. In 1986, the eruption migrated 3 km down the east rift zone to build a broad shield, Kupaianaha, which fed lava to the coast for the next 5.5 years. When the eruption shifted back to Pu‘u ‘O‘o in 1992, a series of flank-vent eruptions formed a shield banked against the uprift side of the cone.
Continuous eruption from these vents undermine west and south flanks of the cone, resulting in large collapses.
Eruption summary
1983-1986, The rise of Pu‘u ‘O‘o
1986-1991, Eruption shifts to Kupaianaha
1992-1994, Eruption returns to Pu‘u ‘O‘o
1995-1998, The fall of Pu‘u ‘O‘o
1999-2000, Intrusion triggers pause in eruption
1983-1986, The rise of Pu‘u ‘O‘o: episodic lava fountains build massive cone.
The Pu‘u ‘O‘o-Kupaianaha eruption began on January 3, 1983. For the first six months, fissures erupted intermittently along the middle east rift zone from Napau Crater to Kalalua (eruptive episodes 1-3). 1983, the activity became localized at the Pu‘u ‘O‘o vent, which straddles the boundary of Hawai‘i Volcanoes National Park. For the next three years (episodes 4-47), Pu‘u ‘O‘o erupted approximately every three to four weeks, usually for less than 24 hours at a time. These eruptive episodes were characterized by spectacular lava fountains that catapulted lava as high as 470 m above the vent
The high fountains produced mainly ‘a‘a flows, the more viscous and crystalline of the two types of Hawaiian lava. ‘A‘a flows from Pu‘u ‘O‘o were typically 3-5 m thick and advanced at speeds of 50-500 m/hr, picking up speed and narrowing on steep slopes. Because of the short duration of each eruptive episode, none of these flows reached the ocean or the coastal highway. The flows posed an immediate threat, however, to the sparsely populated Royal Gardens subdivision, located on a steep slope 6 km southeast of the vent.
‘A‘a flows reached the subdivision in as little as 13 hrs during several eruptive episodes. They destroyed 16 houses in 1983 and 1984. Fallout from the towering lava fountains built a cinder-and-spatter cone 255 m high, over twice the height of any other cone on the east rift zone. The cone was strikingly asymmetric, because the prevailing trade winds caused most of the airborne fragments to pile up on the southwest side of the conduit.
1986-1991, Eruption shifts to Kupaianaha: continuous effusion sends lava to the sea. In July 1986, the vertical conduit of Pu‘u ‘O‘o ruptured and the eruption shifted to a new vent, Kupaianaha, 3 km northeast of Pu‘u ‘O‘o. This marked the end of episodic high fountaining and the beginning of five-and-a-half years of nearly continuous, quiet effusion (episode 48). A lava pond formed over the new vent, and its frequent overflows built a broad, low shield that reached its maximum height of 55 m in less than a year. After weeks of continuous eruption, the main channel exiting from the pond gradually developed a roof as crust at the sides of the channel extended across the lava stream, forming the beginning of a lava tube. Lava tubes insulate rivers of lava from heat loss, producing pahoehoe, a type of lava more fluid than ‘a‘a. The surface of a cooled pahoehoe flow can be flat and smooth, ropy, or undulating.
A broad field of tube-fed pahoehoe spread gradually toward the coast, 12 km to the southeast, taking three months to cover the same distance that ‘a‘a flows from Pu‘u ‘O‘o traveled in less than a day. By early November 1986, the flows were visible on the steep slope above the small community of Kapa‘ahu, and their leisurely pace was no longer reassuring.
Late in November 1986, flows from Kupaianaha reached the ocean, cutting a swath through Kapa‘ahu and closing the coastal highway. A few weeks later, the lava took a more easterly course and overran 14 homes on the northwest edge of Kalapana in a single day. Luckily for the rest of the village, this flow abruptly stagnated when the tube became blocked near the vent.
Over the next three years, lava destroyed homes on either side of the ever-widening flow field. Initially, the course of the pahoehoe flows was strongly influenced by pre-eruption topography, but eventually even the highest ground was inundated. This was not only because pahoehoe re-covered many areas repeatedly, but also because the tube-fed flows thickened from within, inflating as more lava was intruded under the already solid crust of the flow front. From mid-1987 through 1989, most of the lava erupted from Kupaianaha flowed directly to the sea. Steam explosions at the ocean entry fragmented the lava, creating black glassy sand that collected to form new beaches in protected bays down-current from the lava entry. New, albeit unstable, land was added as lava built a series of benches seaward over a steep submarine slope of fragmented lava (see hazards associated with collapsing and exploding lava benches). The long-lived tube system delivering lava to the ocean began to break down in the spring of 1989, and surface flows were a common sight, particularly on the steep slope (Pulama pali) above the coastal plain. Lava flows encroached on new territory, overrunning the Waha‘ula Visitor Center and adjoining residences in Hawai‘i Volcanoes National Park.
The eruption began to change in 1990, when a series of 12 pauses, lasting from 1-4 days, interrupted the steady effusion of lava. At the same time, the eruption entered its most destructive period. In March 1990, the flows turned toward Kalapana, an area cherished for its historic sites and black sand beaches. By the end of the summer, the entire community, including a church, store, and 100 homes, lay buried under 15-25 m of lava (see detailed summary). As the flows advanced eastward, they took to the sea, replacing the palm-lined Kaimu Bay with a plain of lava that extends 300 m beyond the original shoreline. In late 1990, a new lava tube finally diverted lava away from Kalapana and back into the national park, where flows once again entered the ocean.
During the five-and-a-half years that Kupaianaha reigned, repeated collapses of the Pu‘u ‘O‘o conduit gradually formed a crater approximately 300 m in diameter. A lava pond was present sporadically at the bottom of the crater starting in 1987; since 1990 it has been present much of the time.
The volume of lava erupted from Kupaianaha steadily declined through 1991. Concurrently the level and activity of the Pu‘u ‘O‘o lava pond rose. In November 1991, fissures opened between Pu‘u ‘O‘o and Kupaianaha and erupted lava for three weeks. Kupaianaha continued to erupt during this event (episode 49), but its output was waning. On February 7, 1992, the Kupaianaha vent was dead.
1992-1994, Eruption returns to Pu‘u ‘O‘o: flank vents build shield against uprift side of cone Ten days after Kupaianaha stopped erupting, activity returned to Pu‘u ‘O‘o. Lava erupted in low fountains along a fissure on the west flank of the steep-sided cone. This was the first in a series of flank vents that have been active for eight years (episodes 50-53 and episode 55). As at Kupaianaha, the style of the eruption was nearly continuous, quiet effusion.
Episodes 50-53 built a lava shield 45 m high and 1 km in diameter that banked against the western flank of Pu‘u ‘O‘o. In November 1992, lava crossed the Chain of Craters Road in Hawai‘i Volcanoes National Park and entered the ocean at Kamoamoa, 11 km from the vents. Over the next month, tube-fed pahoehoe flows buried the Kamoamoa archaeological site, the National Park’s campground and picnic area, and a black sand beach formed earlier in the eruption when flows from Kupaianaha entered the ocean. From the end of 1992 through January 1997, lava tubes fed lava to the ocean almost continuously, broadening the Kamoamoa flow field, which lies mostly within the National Park.
Beginning in 1993, collapse pits appeared on the west flank of Pu‘u ‘O‘o as lava flowing from the flank vents downcut through tephra beneath the cone. In the next few years, the largest of these, known as the “Great Pit”, would engulf most of the west flank.
1995-1998, The fall of Pu‘u ‘O‘o: collapse claims west flank of cone
On the night of January 30, 1997, Pu‘u ‘O‘o cone changed dramatically. Magma drained from the conduit of Pu‘u ‘O‘o, causing first the crater floor, and then the west wall of the cone, to collapse. Shortly thereafter, new fissures broke open and erupted briefly in and near Napau Crater. This event, designated episode 54, was over in 24 hours.
The collapse created a large gap in the west side of the cone, and the rubble-lined crater was now 210 m deep. For the next 23 days, no active lava was visible at the eruption site.
Episode 55 began on February 24, 1997, when a lava pond returned to the Pu‘u ‘O‘o crater. A month later, lava erupted outside the crater from new vents on the west and southwest flanks of the cone. In April 1997, the active lava pond in Pu‘u ‘O‘o crater was replaced by a single vent in the western part of the crater, known as the “crater vent.” Flows from the crater vent intermittently ponded in the eastern part of the crater. In mid-June 1997, the pond rose until it overtopped the gap in the west wall of Pu‘u ‘O‘o, and lava spilled from the crater for the first time in 11 years. Subsequent crater overflows sent lava over the east crater rim to form flows that spread as far as 1.5 km downrift. The spillovers were brief events, ending when the pond drained through conduits in the crater floor.
Tube-fed flows from the episode 55 flank vents added to the pre-existing Kamoamoa flow field, and lava reached the ocean in July 1997 near the eastern boundary of Hawai‘i Volcanoes National Park. Lava poured into the ocean at two adjacent sites, Waha‘ula and Kamokuna, through 1998.
The most spectacular event in 1998 was a surge in the supply of magma to Pu‘u ‘O‘o on January 14. Lava briefly overflowed the crater (the only time in 1998) and fountains and flows erupted from several collapse pits on the south flank of the cone. For the rest of the year, lava flowed from the south flank vents directly into the tube system.
Downcutting beneath the flank vents continued to remove support for the Pu‘u ‘O‘o cone. A new collapse pit, Puka Nui, began to form in December 1997 on the southwest flank of the cone. By the end of 1998, Puka Nui was more than 175 m in diameter.
1999-2000, Intrusion triggers pause in eruption: tube system blocked
On September 12, 1999, an earthquake swarm and deflation of the summit heralded an intrusion of magma in the upper east rift zone of Kilauea (see summary in eruption archive). The magma conduit supplying Pu‘u ‘O‘o was depressurized as magma was diverted into the upper east rift zone, and the normal supply of magma to the eruption was interrupted for 11 days. A sluggish lava pond appeared at the bottom of the Pu‘u ‘O‘o crater on September 14, but flows didn’t erupt from flank vents until September 23, marking the end of the pause.
Prior to the intrusion, the lava tubes had been holding a steady course for 12 months, feeding lava to the coast where it entered the ocean at the Kamokuna site inside Hawai‘i Volcanoes National Park. During the pause, however, the long-lived tube system became permanently blocked near the 2250 ft elevation, about 10 km from the coast. When the eruption resumed, surface flows broke out of the tube at this elevation. Over the next several weeks, hundreds of short surface flows built a series of shields that coalesced to form a prominent ridge along the axis of the tube. Eventually, longer flows moved down the pali on the west and east sides of the episode 55 flow field. New tubes developed within these flows. Lava finally reached the ocean in mid December at Highcastle and Lae‘apuki. The Highcastle entry was short lived, but the Lae‘apuki entry continued into the new year. In February 2000, the eastern branch of the flow reached the ocean near the site of Waha‘ula. By the end of March 2000, the Lae‘apuki entry had died, and lava was spilling into the sea at several locations in the Waha‘ula area.
Current eruption update References Heliker, C., Mangan, M.T., and Mattox, T.N., 1998, The character of long-term eruptions: inferences from episodes 50-53 of the Pu‘u ‘O‘o-Kupaianaha eruption of Kilauea Volcano: Bulletin of Volcanology, v. 59, p. 381-393.
Heliker, C., and Wright, T.L., 1991, Lava-flow hazards from Kilauea:
Geotimes, May 1991, p. 16-19.
Mattox, T.N., Heliker, C., Kauahikaua, J., and Hon, K., 1993, Development of the 1990 Kalapana flow field, Kilauea Volcano, Hawaii: Bulletin of Volcanology, v. 55, p. 407-413. Wolfe, E.W. (ed), 1988, The Pu‘u ‘O‘o eruption of Kilauea Volcano:
U.S. Geological Survey Professional Paper 1463, 251 p.
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