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Kīlauea Iki is a pit crater that is next to the main summit caldera of Kīlauea on the island of Hawaiʻi in the Hawaiian Islands. It is known for its eruption in 1959 that started on November 14 and ended on December 20, producing lava fountaining up to 1900 feet and a lava lake in the crater. Today, the surface of the lava lake has cooled and it is now a popular hiking destination to view the aftermath of an eruption.
Lava tubes associated with Kīlauea Iki are responsible for the vast ʻAilāʻau eruption, carbon 14 dated from c. 1445 and erupting continuously for approximately 50 years, which blanketed much of what is now Puna District with 5.2 ± 0.8 km3 of basalt lava. [1]
Kilauea Iki experienced a minor eruption in 1868, which covered the floor of the crater in a thin layer of basalt. [2] This eruption was preceded by the great Ka'ü earthquake of 1868, a magnitude 7.9 earthquake that caused extensive damage on the island and resulted in collapses of the wall in Kilauea's summit caldera, withdrawal of lava from the summit caldera, and the brief eruption in Kilauea Iki. [3]
At 8:08 pm on November 14, 1959, an eruption began at the summit of Kilauea in the Kilauea Iki crater after several months of increased seismicity and deformation. [4] Over the next month, the crater experienced 17 eruption episodes, each one (except for the last) beginning with lava fountaining and ending with lava drainback. [5] [6] After the first episode, which lasted 7 days, most of the remaining episodes were less than 24 hours, with the shortest (14th episode) lasting less than 2 hours. [4] [3] Volcanic ejecta from the main fissure on the western side of the crater formed the 70 meter high Pu'u Pua'i tephra cone (Hawaiian for 'gushing hill'). [5] [7] On December 11, 1959, at the end of the 8th episode, the lava lake formed in the crater reached its greatest volume (58 million cubic yards) and depth (414 feet). [4] The final volume and depth of the lava lake after the end of the eruption on December 20 was approximately 50 million cubic yards and 365 feet, respectively. [4] [3] In 1988, a drilling project of Kilauea Iki showed that the lava lake depth was deeper than expected by 50-90 feet. [2] This was likely due to the crater floor collapsing during the 1959 eruption. [2] [3]
Early warning signs of the impending eruption included outward tilting at the summit region and increased seismicity. [4] [3] [8] Tiltmeter measurements between November 1957 and February 1959 indicated that magma was migrating towards the summit, causing swelling of the ground surface. [4] Swelling ceased and deflation of the summit began after several earthquakes occurred on February 19, 1959. [4] Slow deflation continued until a swarm of earthquakes in mid-August 1959 led to resumption of rapid swelling that continued until the eruption in November. [4] [8] Most of these earthquake swarms were at a depth of 40-60 km and likely related to upward magma movement from the mantle. [3] By early November, more than 1,000 earthquakes were being recorded each day and tiltmeter measurements indicated swelling 3 times faster than previous rates. [4] [8]
Lava fountaining is characteristic of Hawaiian eruptions and the 1959 eruption of Kilauea Iki produced some of the highest lava fountains ever observed in Hawaii. [3] [9] At the beginning of the eruption, the fountain height was only 30 m, but this increased over the next several days to between 200 and 300 m. [5] On November 21, the fountain went from 210 meters tall to a few gas bubbles in less than 40 seconds. [5] Some of the fountains were extraordinarily high, with the 15th episode producing a fountain reaching nearly 580 m (1,900 ft), among the highest ever recorded. [5] [9] After the end of each eruption episode, lava drained back into the vent which may have acted as a coolant for the underlying material, resulting in the triggering of the next episode of lava fountaining. [10]
Lava drainback is common during eruptions at Kilauea and occurs when magma erupts at the surface, forming a lava lake and then draining back below ground. [11] [8] During the Kilauea Iki eruption, the level of the lava lake would rise until it reached the erupting vent partway up the crater wall, where lava drainback would begin. [6] [4] [11] The first episode had 31 million cubic meters of lava flow into Kīlauea Iki with 1 million cubic meters draining back. [8] During the following episodes, a total of 71 million cubic meters of lava was ejected during a month-long eruption that stopped on December 20, 1959. [8] Only 8 million cubic meters of lava remained, with 63 million cubic meters of lava draining back into the Kīlauea magma reservoir. [8] Often the lava drainback had a higher rate of flow than the eruptions. [8]
With every filling and draining of the lava lake, a 'black ledge' was formed along the rim of the crater which marked the level of the lava lake during each eruption episode. [6] [8] During lava drainbacks, a giant counter-clockwise whirlpool would form. [4]
Samples collected from the first episode of the eruption were composed of two different kinds of magma. [3] [12] The first variant was identical to previous magmas erupted in the 1954 Kilauea caldera eruption and the second variant had a composition different from anything seen at previous eruptions, with a high ratio of CaO to MgO. [3] Subsequent eruption episodes produced samples that were a mixture of the two variants plus some additional amount of olivine. [12] The reason for two different magma compositions may be two magma storage areas beneath Kilauea Iki that had higher olivine concentrations at the bottom. [12] At the beginning of the eruption, both magma sources provided material to the surface, while later eruption episodes at the single vent on the west side of the caldera contained a mixture of the two magmas. [12] [3] Additionally, the later eruption episodes were sourced from deeper sections of the magma chambers, resulting in higher concentrations of olivine. [12] [10]
Drivers may view Kīlauea Iki from either a lookout point or the trailhead parking lot. Guests can hike across Kīlauea Iki by descending from Byron Ledge, which overlooks the crater. The trail crosses the floor of the crater, which once was a lake of lava. Even after 50 years, the parts of the surface are still warm to the touch. Rainwater seeps into the cracks and makes contact with the extremely hot rock below and steam is emitted from various surface cracks. The steam and some rocks are hot enough to cause serious burns.
A caldera is a large cauldron-like hollow that forms shortly after the emptying of a magma chamber in a volcanic eruption. An eruption that ejects large volumes of magma over a short period of time can cause significant detriment to the structural integrity of such a chamber, greatly diminishing its capacity to support its own roof, and any substrate or rock resting above. The ground surface then collapses into the emptied or partially emptied magma chamber, leaving a large depression at the surface. Although sometimes described as a crater, the feature is actually a type of sinkhole, as it is formed through subsidence and collapse rather than an explosion or impact. Compared to the thousands of volcanic eruptions that occur over the course of a century, the formation of a caldera is a rare event, occurring only a few times within a given window of 100 years. Only eight caldera-forming collapses are known to have occurred between 1911 and 2018, with a caldera collapse at Kīlauea, Hawaii in 2018. Volcanoes that have formed a caldera are sometimes described as "caldera volcanoes".
A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface.
Mauna Loa is one of five volcanoes that form the Island of Hawaii in the U.S. state of Hawaii in the Pacific Ocean. Mauna Loa is Earth's largest active volcano by both mass and volume. It was historically considered to be the largest volcano on Earth until Tamu Massif was discovered to be larger. Mauna Loa is a shield volcano with relatively gentle slopes, and a volume estimated at 18,000 cubic miles (75,000 km3), although its peak is about 125 feet (38 m) lower than that of its neighbor, Mauna Kea. Lava eruptions from Mauna Loa are silica-poor and very fluid, and tend to be non-explosive.
A shield volcano is a type of volcano named for its low profile, resembling a shield lying on the ground. It is formed by the eruption of highly fluid lava, which travels farther and forms thinner flows than the more viscous lava erupted from a stratovolcano. Repeated eruptions result in the steady accumulation of broad sheets of lava, building up the shield volcano's distinctive form.
Kīlauea is an active shield volcano in the Hawaiian Islands. It is located along the southeastern shore of Hawaii Island. The volcano is between 210,000 and 280,000 years old and grew above sea level about 100,000 years ago. Since the islands were settled, it has been the most active of the five volcanoes that together form the island and among the most active volcanoes on Earth. The most recent eruption occurred on June 3, 2024, along fissures that opened on the volcano's southwest rift zone.
Mount Pinatubo is an active stratovolcano in the Zambales Mountains, located on the tripoint boundary of the Philippine provinces of Zambales, Tarlac and Pampanga, all in Central Luzon on the northern island of Luzon. Most people were unaware of its eruptive history before the pre-eruption volcanic activity in early 1991. Dense forests, which supported a population of several thousand indigenous Aetas, heavily eroded and obscured Pinatubo.
Puʻu ʻŌʻō is a volcanic cone on the eastern rift zone of Kīlauea volcano in the Hawaiian Islands. The eruption that created Puʻu ʻŌʻō began on January 3, 1983, and continued nearly continuously until April 30, 2018, making it the longest-lived rift-zone eruption of the last two centuries.
A Hawaiian eruption is a type of volcanic eruption where lava flows from the vent in a relatively gentle, low level eruption; it is so named because it is characteristic of Hawaiian volcanoes. Typically they are effusive eruptions, with basaltic magmas of low viscosity, low content of gases, and high temperature at the vent. Very small amounts of volcanic ash are produced. This type of eruption occurs most often at hotspot volcanoes such as Kīlauea on Hawaii's big island and in Iceland, though it can occur near subduction zones and rift zones. Hawaiian eruptions may occur along fissure vents, such as during the eruption of Mauna Loa in 1950, or at a central vent, such as during the 1959 eruption in Kīlauea Iki Crater, which created a lava fountain 580 meters (1,900 ft) high and formed a 38-meter cone named Puʻu Puaʻi. In fissure-type eruptions, lava spurts from a fissure on the volcano's rift zone and feeds lava streams that flow downslope. In central-vent eruptions, a fountain of lava can spurt to a height of 300 meters or more.
Lava lakes are large volumes of molten lava, usually basaltic, contained in a volcanic vent, crater, or broad depression. The term is used to describe both lava lakes that are wholly or partly molten and those that are solidified.
Cerro Galán is a caldera in the Catamarca Province of Argentina. It is one of the largest exposed calderas in the world and forms part of the Central Volcanic Zone of the Andes, one of the three volcanic belts found in South America. One of several major caldera systems in the Central Volcanic Zone, the mountain is grouped into the Altiplano–Puna volcanic complex.
Tolmachev Dol is a volcanic highland located in the southern part of Kamchatka Peninsula, Russia, northeast of Opala volcano. The cones and lava fields cover a broad area around Lake Tolmachev.
A rift zone is a feature of some volcanoes, especially shield volcanoes, in which a set of linear cracks develops in a volcanic edifice, typically forming into two or three well-defined regions along the flanks of the vent. Believed to be primarily caused by internal and gravitational stresses generated by magma emplacement within and across various regions of the volcano, rift zones allow the intrusion of magmatic dykes into the slopes of the volcano itself. The addition of these magmatic materials usually contributes to the further rifting of the slope, in addition to generating fissure eruptions from those dykes that reach the surface. It is the grouping of these fissures, and the dykes that feed them, that serves to delineate where and whether a rift zone is to be defined. The accumulated lava of repeated eruptions from rift zones along with the endogenous growth created by magma intrusions causes these volcanoes to have an elongated shape. Perhaps the best example of this is Mauna Loa, which in Hawaiian means "long mountain", and which features two very well defined rift zones extending tens of kilometers outward from the central vent.
Halemaʻumaʻu is a pit crater within the much larger Kīlauea Caldera at the summit of Kīlauea volcano on island of Hawaiʻi. 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. Following the collapses of 2018, the bottom of Halemaʻumaʻu was roughly 600 m (2,000 ft) below the caldera floor. Halemaʻumaʻu is home to Pele, goddess of fire and volcanoes, according to the traditions of Hawaiian religion. Halemaʻumaʻu means "house of the ʻāmaʻu fern".
Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet or a moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust, on land or underwater, usually at temperatures from 800 to 1,200 °C. The volcanic rock resulting from subsequent cooling is also often called lava.
Lake Pinatubo is the summit crater lake of Mount Pinatubo formed after its climactic eruption on June 15, 1991. The lake is located in Botolan, Zambales, near the boundaries of Pampanga and Tarlac provinces in the Philippines. It is about 90 km (56 mi) northwest of the capital city of Manila. While one paper by researchers from Japan suggested a depth of 600 m (2,000 ft), more detailed research suggests that 95–115 m (312–377 ft) is more accurate.
Hualca Hualca is an extinct volcano in Arequipa Region in the Andes of Peru. It has a height of 6,025 metres (19,767 ft). It is located at the Peruvian province of Caylloma.
Devastation Trail is a trail in Hawaiʻi Volcanoes National Park. The paved trail allows visitors to explore the site of 1959 eruption of Kīlauea Iki crater.
Tarso Yega is a stratovolcano in Tibesti, with a summit caldera that is 19 by 20 kilometres wide and 300 metres (980 ft) deep. The summit of the volcano reaches a height of 2,972 metres (9,751 ft), and its caldera is the largest caldera of the Tibesti. Neighbouring volcanoes include Doudriki east, Ehi Dosoatou south and Ehi Fodoboro southwest of the caldera. The Enneri Yega river drains the caldera westward and then south, before joining the Enneri Debarsar; in the past (Holocene) the rivers reached Lake Chad and lakes formed in Tarso Yega.
Ubinas is an active stratovolcano in the Moquegua Region of southern Peru, approximately 60 kilometres (37 mi) east of the city of Arequipa. Part of the Central Volcanic Zone of the Andes, it rises 5,672 metres (18,609 ft) above sea level. The volcano's summit is cut by a 1.4-kilometre-wide (0.87 mi) and 150-metre-deep (490 ft) caldera, which itself contains a smaller crater. Below the summit, Ubinas has the shape of an upwards-steepening cone with a prominent notch on the southern side. The gently sloping lower part of the volcano is also known as Ubinas I and the steeper upper part as Ubinas II; they represent different stages in the volcano's geological history.
The 1960 eruption of Kīlauea occurred from January 13 to February 19, 1960, on Kīlauea, the most active volcano in Hawaii, USA. It followed the eruption of late 1959 in Kīlauea Iki, near the volcano's summit. Fissure vents opened up on the eastern tip of the island of Hawaii, just outside the town of Kapoho. Fountains of lava erupt from these fissures, forming a flow that advances into the Pacific Ocean. As the lava threatened homes, several makeshift dykes were erected in quick succession, but they were soon overtopped and Kapoho was finally destroyed. At the summit of the volcano, earthquakes hit the caldera rim and three collapses affect the floor of the Halemaʻumaʻu crater, with lava appearing as a remnant of a previous eruption. After an eruption lasting just over a month, the third most powerful to hit Kīlauea in the 20th century, the lava covered more than 10 square kilometers of land, including 2 square kilometers of sea, and pushed Cape Kumukahi, the easternmost point of the island of Hawaii, a little further east.
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