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120-514: Mauna Kea ( / ˌ m ɔː n ə ˈ k eɪ ə , ˌ m aʊ n ə -/ , Hawaiian: [ˈmɐwnə ˈkɛjə] ; abbreviation for Mauna a Wākea ) is a dormant shield volcano on the island of Hawaiʻi . Its peak is 4,207.3 m (13,803 ft) above sea level, making it the highest point in Hawaii and the island with the second highest high point , behind New Guinea, the world's largest tropical island with multiple peaks that are higher. The peak

240-460: A circular ring of till and gravel along the volcano's upper flanks. Subglacial eruptions built cinder cones during the Mākanaka glaciation, most of which were heavily gouged by glacial action. The most recent cones were built between 9,000 and 4,500 years ago, atop the glacial deposits, although one study indicates that the last eruption may have been around 3,600 years ago. At their maximum extent,

360-487: A depth of 3 m (10 ft) when fullest. Radiocarbon dating of samples at the base of the lake indicates that it was clear of ice 12,600 years ago. Hawaiian lava types are typically permeable , preventing lake formation due to infiltration . Either sulfur-bearing steam altered the volcanic ash to low-permeability clays, or explosive interactions between rising magma and groundwater or surface water during phreatic eruptions formed exceptionally fine ash that reduced

480-451: A drop of a degree in temperature allowed snow to remain at the volcano's summit through summer, triggering the formation of an ice cap . There are three episodes of glaciation that have been recorded from the last 180,000 years: the Pōhakuloa (180–130  ka ), Wāihu (80–60 ka) and Mākanaka (40–13 ka) series. These have extensively sculpted the summit, depositing moraines and

600-545: A far greater distance than those of other eruptive types before solidifying, forming extremely wide but relatively thin magmatic sheets often less than 1 m (3 ft) thick. Low volumes of such lavas layered over long periods of time are what slowly constructs the characteristically low, broad profile of a mature shield volcano. Also unlike other eruptive types, Hawaiian eruptions often occur at decentralized fissure vents , beginning with large "curtains of fire" that quickly die down and concentrate at specific locations on

720-457: A further 13 km (8 mi) below the waterline and into the crust, approximately 80,000 km (19,000 cu mi) of rock. Kīlauea , another Hawaiian shield volcano, is one of the most active volcanoes on Earth, with its most recent eruption occurring in 2021. The Galápagos Islands are an isolated set of volcanoes, consisting of shield volcanoes and lava plateaus, about 1,100 km (680 mi) west of Ecuador. They are driven by

840-466: A highly endangered endemic plant species that thrives in Mauna Kea's high elevation cinder deserts. At one stage reduced to a population of just 50 plants, Mauna Kea silversword was thought to be restricted to the alpine zone, but in fact has been driven there by pressure from livestock, and can grow at lower elevations as well. The Mauna Kea Ice Age Reserve on the southern summit flank of Mauna Kea

960-569: A plan to support the continued development of scientific facilities at the site. In 1998, 2,033 acres (823 ha) were transferred from the observatory lease to supplement the Mauna Kea Ice Age Reserve. The 1982 plan was replaced in 2000 by an extension designed to serve until 2020: it instituted an Office of Mauna Kea Management, designated 525 acres (212 ha) for astronomy, and shifted the remaining 10,763 acres (4,356 ha) to "natural and cultural preservation". This plan

1080-583: A prominent feature on these volcanoes and account for their seemingly random volcanic structure. They are fueled by the movement of the Pacific Plate over the Hawaii hotspot and form a long chain of volcanoes, atolls , and seamounts 2,600 km (1,616 mi) long with a total volume of over 750,000 km (179,935 cu mi). The chain includes Mauna Loa, a shield volcano which stands 4,170 m (13,680 ft) above sea level and reaches

1200-440: A single point. The main shield then forms, burying the smaller ones formed by the early eruptions with its lava. Icelandic shields are mostly small (~15 km (4 cu mi)), symmetrical (although this can be affected by surface topography), and characterized by eruptions from summit calderas. They are composed of either tholeiitic olivine or picritic basalt . The tholeiitic shields tend to be wider and shallower than

1320-475: A staple food source. Early settlement of the Hawaiian islands led to major changes to local ecosystems and many extinctions, particularly amongst bird species. Ancient Hawaiians brought foreign plants and animals, and their arrival was associated with increased rates of erosion. The prevailing lowland forest ecosystem was transformed from forest to grassland; some of this change was caused by the use of fire, but

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1440-461: Is Nyamuragira . Eruptions at the shield volcano are generally centered within the large summit caldera or on the numerous fissures and cinder cones on the volcano's flanks. Lava flows from the most recent century extend down the flanks more than 30 km (19 mi) from the summit, reaching as far as Lake Kivu . Erta Ale in Ethiopia is another active shield volcano and one of the few places in

1560-504: Is a highly unusual food source for a species in the genus Nysius , which consists of predominantly seed-eating insects. They can survive at extreme elevations of up to 4,200 m (13,780 ft) because of natural antifreeze in their blood. They also stay under heated surfaces most of the time. Their conservation status is unclear, but the species is no longer a candidate for the Endangered Species List ; studies on

1680-407: Is a list of mountain peaks ordered by their topographic prominence . The prominence of a peak is the minimum height of climb to the summit on any route from a higher peak, or from sea level if there is no higher peak. The lowest point on that route is the col . For full definitions and explanations of topographic prominence , key col , and parent , see topographic prominence . In particular,

1800-667: Is a shield volcano on the southwestern part of Isabela Island and is one of the most active in the Galapagos, with the last eruption between May and June 2008. The Geophysics Institute at the National Polytechnic School in Quito houses an international team of seismologists and volcanologists whose responsibility is to monitor Ecuador's numerous active volcanoes in the Andean Volcanic Belt and

1920-517: Is about 38 m (125 ft) higher than Mauna Loa , its more massive neighbor. Mauna Kea is unusually topographically prominent for its height: its prominence from sea level is fifteenth in the world among mountains, at 4,207.3 m (13,803 ft); its prominence from under the ocean is 9,330 m (30,610 ft), rivaled only by Mount Everest . This dry prominence is greater than Everest's height above sea level of 8,848.86 m (29,032 ft), and some authorities have labeled Mauna Kea

2040-415: Is above the inversion layer , keeping most cloud cover below the summit and ensuring the air on the summit is dry, and free of atmospheric pollution . The summit atmosphere is exceptionally stable, lacking turbulence for some of the world's best astronomical seeing . The very dark skies resulting from Mauna Kea's distance from city lights are preserved by legislation that minimizes light pollution from

2160-531: Is common in Hawaiʻi; most Hawaiian eruptions begin with a so-called "wall of fire" along a major fissure line before centralizing to a small number of points. This accounts for their asymmetrical shape, whereas Icelandic volcanoes follow a pattern of central eruptions dominated by summit calderas , causing the lava to be more evenly distributed or symmetrical. Most of what is currently known about shield volcanic eruptive character has been gleaned from studies done on

2280-422: Is currently active, having last erupted between 4,500 and 6,000 years ago. Mauna Kea does not have a visible summit caldera , but contains a number of small cinder and pumice cones near its summit. A former summit caldera may have been filled and buried by later summit eruption deposits. Mauna Kea is over 32,000 km (7,680 cu mi) in volume, so massive that it and its neighbor, Mauna Loa , depress

2400-528: Is encompassed by the Mauna Kea State Recreation Area . A band of ranch land on Mauna Kea's lower slopes was formerly Acacia koa – Metrosideros polymorpha (koa-ʻōhiʻa) forest. Its destruction was driven by an influx of European and American settlers in the early 19th century, as extensive logging during the 1830s provided lumber for new homes. Vast swathes of the forest were burned and cleared for sugarcane plantations. Most of

2520-504: Is expected to erupt again. Based on earlier eruptions, such an event could occur anywhere on the volcano's upper flanks and would likely produce long lava flows, mostly of ʻaʻā , 15–25 km (9–16 mi) long. Long periods of activity could build a cinder cone at the source. Although not likely in the next few centuries, such an eruption would probably result in little loss of life but significant damage to infrastructure. The first Ancient Hawaiians to arrive on Hawaiʻi island lived along

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2640-491: Is loosely defined, which has resulted in numbers ranging from 9,966 m (32,696 ft) (roughly to the deepest point in the Hawaiian Trough) to 17,205 m (56,447 ft) (to the root of the mountain deep underground). Those calculations have produced rivaling claims for other mountains, such as higher climb from base for Mount Lamlam (11,528 m (37,820 ft), starting from nearby Challenger Deep ), and

2760-493: Is not a shield volcano. Shield volcanoes feature a gentle (usually 2° to 3°) slope that gradually steepens with elevation (reaching approximately 10°) before flattening near the summit, forming an overall upwardly convex shape. These slope characteristics have a correlation with age of the forming lava, with in the case of the Hawaiian chain, steepness increasing with age, as later lavas tend to be more alkali so are more viscous, with thicker flows, that travel less distance from

2880-414: Is now confined to the slopes of Mauna Kea—only 10% of its former range—and has been declared critically endangered . The largest threat to the ecosystem is grazing by feral sheep, cattle ( Bos primigenius ), and goats ( Capra hircus ) introduced to the island in the late 18th century. Feral animal competition with commercial grazing was severe enough that a program to eradicate them existed as far back as

3000-600: Is one of five volcanoes that form the island of Hawaiʻi , the largest and youngest island of the Hawaiian–Emperor seamount chain . Of these five hotspot volcanoes , Mauna Kea is the fourth oldest and fourth most active. It began as a preshield volcano driven by the Hawaiʻi hotspot around one million years ago, and became exceptionally active during its shield stage until 500,000 years ago. Mauna Kea entered its quieter post-shield stage 250,000 to 200,000 years ago, and

3120-399: Is relatively smooth and flows with a ropey texture, and ʻaʻā flows which are denser, more viscous (and thus slower moving) and blockier. These lava flows can be anywhere between 2 and 20 m (10 and 70 ft) thick. ʻAʻā lava flows move through pressure— the partially solidified front of the flow steepens because of the mass of flowing lava behind it until it breaks off, after which

3240-472: Is taller than Mount Everest's height above sea level of 8,848.86 m (29,032 ft), so Everest would have to include whole continents in its foothills to exceed Mauna Kea's dry prominence. Given how much Mauna Kea protrudes from the Hawaiian Trough , some authorities have called it the tallest (as opposed to highest ) mountain in the world, as measured from base to peak. Unlike prominence, base

3360-461: Is the peak whose territory peak A resides in. The encirclement parent is found by tracing the contour below peak A's key col and picking the highest mountain in that region. This is easier to determine than the prominence parent; however, it tends to give non-intuitive results for peaks with very low cols such as Jabal Shams which is #110 in the list. Either sort of parent of a typical very high-prominence peak such as Denali will lie far away from

3480-533: Is unusually topographically prominent for its height, with a wet prominence fifteenth in the world among mountains, and a dry prominence second in the world , after only Mount Everest . It is the highest peak on its island, so its wet prominence matches its height above sea level, at 4,207.3 m (13,803 ft). Because the Hawaiian Islands slope deep into the ocean, Mauna Kea has a dry prominence of 9,330 m (30,610 ft). This dry prominence

3600-479: The Galápagos hotspot , and are between approximately 4.2 million and 700,000 years of age. The largest island, Isabela , consists of six coalesced shield volcanoes, each delineated by a large summit caldera. Española , the oldest island, and Fernandina , the youngest, are also shield volcanoes, as are most of the other islands in the chain. The Galápagos Islands are perched on a large lava plateau known as

3720-685: The Mid-Atlantic Ridge , a divergent tectonic plate boundary in the middle of the Atlantic Ocean, Iceland is the site of about 130 volcanoes of various types. Icelandic shield volcanoes are generally of Holocene age, between 5,000 and 10,000 years old. The volcanoes are also very narrow in distribution, occurring in two bands in the West and North Volcanic Zones. Like Hawaiian volcanoes, their formation initially begins with several eruptive centers before centralizing and concentrating at

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3840-564: The Pacific tectonic plate has moved over the Hawaiian hotspot in the Earth's underlying mantle . The Hawaii island volcanoes are the most recent evidence of this process that, over 70 million years, has created the 6,000 km (3,700 mi)-long Hawaiian Ridge–Emperor seamount chain. The prevailing, though not completely settled, view is that the hotspot has been largely stationary within

3960-767: The Purico complex in Chile ; an example of a felsic shield is the Ilgachuz Range in British Columbia , Canada. Shield volcanoes are similar in origin to vast lava plateaus and flood basalts present in various parts of the world. These are eruptive features which occur along linear fissure vents and are distinguished from shield volcanoes by the lack of an identifiable primary eruptive center. Active shield volcanoes experience near-continuous eruptive activity over extremely long periods of time, resulting in

4080-591: The US Air Force and Lowell Observatory . In 1973, Canada and France agreed to build the 3.6 m CFHT on Mauna Kea. However, local organisations started to raise concerns about the environmental impact of the observatory. This led the Department of Land and Natural Resources to prepare an initial management plan, drafted in 1977 and supplemented in 1980. In January 1982, the UH Board of Regents approved

4200-497: The University of Houston 's William Sager announced the discovery of Tamu Massif , an enormous extinct submarine volcano, approximately 450 by 650 km (280 by 400 mi) in area, which dwarfs all previously known volcanoes on Earth. However, the extents of the volcano have not been confirmed. Although Tamu Massif was initially believed to be a shield volcano, Sanger and his colleagues acknowledged in 2019 that Tamu Massif

4320-468: The ocean crust beneath it by 6 km (4 mi). The volcano continues to slip and flatten under its own weight at a rate of less than 0.2 mm (0.01 in) per year. Much of its mass lies east of its present summit. It stands 4,207.3 m (13,803 ft) above sea level, about 38 m (125 ft) higher than its neighbor Mauna Loa, and is the highest point in the state of Hawaii . Like all Hawaiian volcanoes, Mauna Kea has been created as

4440-421: The 1976–1979 Viking mission . The principal difference between the volcanoes of Mars and those on Earth is in terms of size; Martian volcanoes range in size up to 14 mi (23 km) high and 370 mi (595 km) in diameter, far larger than the 6 mi (10 km) high, 74 mi (119 km) wide Hawaiian shields. The highest of these, Olympus Mons , is the tallest known mountain on any planet in

4560-568: The Galapagos Islands. La Cumbre is an active shield volcano on Fernandina Island that has been erupting since April 11, 2009. The Galápagos islands are geologically young for such a big chain, and the pattern of their rift zones follows one of two trends, one north-northwest, and one east–west. The composition of the lavas of the Galápagos shields are strikingly similar to those of the Hawaiian volcanoes. Curiously, they do not form

4680-535: The Galápagos Platform. This platform creates a shallow water depth of 360 to 900 m (1,181 to 2,953 ft) at the base of the islands, which stretch over a 174 mi (280 km) diameter. Since Charles Darwin 's visit to the islands in 1835 during the second voyage of HMS Beagle , there have been over 60 recorded eruptions in the islands, from six different shield volcanoes. Of the 21 emergent volcanoes, 13 are considered active. Cerro Azul

4800-455: The Hawaiian crow in particular is extinct in the wild , but there are plans to reintroduce the species into the Hakalau reserve. Mauna Kea's summit is one of the best sites in the world for astronomical observation due to favorable observing conditions. The arid conditions are important for submillimeter and infrared astronomy for this region of the electromagnetic spectrum . The summit

4920-508: The Hawaiʻi Department of Land and Natural Resources gave it a 65-year lease for all land within a 4 km (2.5 mi) radius of its telescope, essentially that above 11,500 ft (3,505 m). On its completion in 1970, the UH 88 in (2.2 m) was the seventh largest optical/infrared telescope in the world. By 1970, two 24 in (0.6 m) telescopes had been constructed by

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5040-639: The University of Hawaiʻi's Center for the Study of Active Volcanoes believes one reason to continue study of the aquifers is due to use and occupancy of the higher elevation areas, stating: "Nearly all of these activities depend on the availability of potable water that, in most cases, must be trucked to the Saddle from Waimea or Hilo — an inefficient and expensive process that consumes a substantial quantity of our scarce liquid fuels." The last eruption of Mauna Kea

5160-454: The ahupuaʻa of Kaʻohe, with part of its eastern slope reaching into the nearby Humuʻula. Principal sources of nutrition for Hawaiians living on the slopes of the volcano came from the māmane– naio forest of its upper slopes, which provided them with vegetation and bird life. Bird species hunted included the ʻuaʻu ( Pterodroma sandwichensis ), nēnē ( Branta sandvicensis ), and palila ( Loxioides bailleui ). The lower koa – ʻōhiʻa forest gave

5280-497: The area. Mauna Kea has been the site of extensive archaeological research since the 1980s. Approximately 27 percent of the Science Reserve had been surveyed by 2000, identifying 76 shrines, 4 adze manufacturing workshops, 3 other markers, 1 positively identified burial site, and 4 possible burial sites. By 2009, the total number of identified sites had risen to 223, and archaeological research on

5400-402: The back-and-forth between the ranchers and hunters eventually gave way to a rise in public environmental concern. With the development of astronomical facilities on Mauna Kea commencing, conservationists demanded protection of Mauna Kea's ecosystem. A plan was proposed to fence 25% of the forests for protection, and manage the remaining 75% for game hunting. Despite opposition from conservationists

5520-508: The central Mexican Michoacán–Guanajuato volcanic field average 340 m (1,100 ft) in height and 4,100 m (13,500 ft) in width, with an average slope angle of 9.4° and an average volume of 1.7 km (0.4 cu mi). Rift zones are a prevalent feature on shield volcanoes that is rare on other volcanic types. The large, decentralized shape of Hawaiian volcanoes as compared to their smaller, symmetrical Icelandic cousins can be attributed to rift eruptions. Fissure venting

5640-410: The creation of an access road in 1964, thirteen telescopes funded by eleven countries have been constructed at the summit. The Mauna Kea Observatories are used for scientific research across the electromagnetic spectrum and comprise the largest such facility in the world. Their construction on a landscape considered sacred by Native Hawaiians continues to be a topic of debate to this day . Mauna Kea

5760-464: The cultivation of eucalyptus for wood pulp . The Hakalau Forest National Wildlife Refuge is a major koa forest reserve on Mauna Kea's windward slope. It was established in 1985, covering 32,733 acres (13,247 ha) of ecosystem remnant. Eight endangered bird species, twelve endangered plants, and the endangered Hawaiian hoary bat ( Lasiurus cinereus semotus ) have been observed in the area, in addition to many other rare biota. The reserve has been

5880-420: The different definitions of the parent of a peak are addressed at length in that article. Height on the other hand simply means elevation of the summit above sea level. Regarding parents, the prominence parent of peak A can be found by dividing the island or region in question into territories, by tracing the runoff from the key col ( mountain pass ) of every peak that is more prominent than peak A. The parent

6000-408: The early 19th century brought more settlers to the island, and had a lasting negative ecological effect. On lower slopes, vast tracts of koa–ʻōhiʻa forest were converted to farmland. Higher up, feral animals that escaped from ranches found refuge in, and damaged extensively, Mauna Kea's native māmane–naio forest. Non-native plants are the other serious threat; there are over 4,600 introduced species on

6120-661: The effects of invasive species . In addition the ecosystems of Hawaiʻi are under threat from human development including the clearing of land for agriculture; an estimated third of the island's endemic species have already been wiped out. Because of its elevation, Mauna Kea has the greatest diversity of biotic ecosystems anywhere in the Hawaiian archipelago. Ecosystems on the mountain form concentric rings along its slopes due to changes in temperature and precipitation with elevation. These ecosystems can be roughly divided into three sections by elevation: alpine – subalpine , montane , and basal forest . Contact with Americans and Europeans in

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6240-481: The enormous main mass of the volcano are tholeiitic basalts , like those of Mauna Loa, created through the mixing of primary magma and subducted oceanic crust. They are covered by the oldest exposed rock strata on Mauna Kea, the post-shield alkali basalts of the Hāmākua Volcanics , which erupted between 250,000 and 70–65,000 years ago. The most recent volcanic flows are hawaiites and mugearites : they are

6360-441: The establishment of trade; and the adze quarries on Mauna Kea were abandoned after the introduction of metal tools. In 1793, cattle were brought by George Vancouver as a tribute to King Kamehameha I . By the early 19th century, they had escaped confinement and roamed the island freely, greatly damaging its ecosystem. In 1809 John Palmer Parker arrived and befriended Kamehameha I, who put him in charge of cattle management on

6480-609: The exposed Mauna Kea surface and had subsequently been subsided below sea level. Isotopic composition shows the water present to have been derived from rain coming off Mauna Kea at higher than 2,000 m (6,600 ft) above mean sea level. The aquifer's presence is attributed to a freshwater head within Mauna Kea's basal lens. Scientists believe there may be more water in Mauna Kea's freshwater lens than current models may indicate. Two more boreholes were drilled on Mauna Kea in 2012, with water being found at much higher elevations and shallower depths than expected. Donald Thomas, director of

6600-423: The finished product. Lake Waiau provided drinking water for the workers. Native chiefs would also dip the umbilical cords of newborn babies in its water, to give them the strength of the mountain. Use of the quarry declined between this period and contact with Americans and Europeans. As part of the ritual associated with quarrying, the workers erected shrines to their gods; these and other quarry artifacts remain at

6720-484: The former sugar industry , at its base. In recent years, concern over the vulnerability of the native species has led to court cases that have forced the Hawaiʻi Department of Land and Natural Resources to work towards eradicating all feral species on the volcano. With its high elevation, dry environment, and stable airflow, Mauna Kea's summit is one of the best sites in the world for astronomical observation. Since

6840-410: The general mass behind it moves forward. Though the top of the flow quickly cools down, the molten underbelly of the flow is buffered by the solidifying rock above it, and by this mechanism, ʻaʻā flows can sustain movement for long periods of time. Pāhoehoe flows, in contrast, move in more conventional sheets, or by the advancement of lava "toes" in snaking lava columns. Increasing viscosity on the part of

6960-409: The glaciers extended from the summit down to between 3,200 and 3,800 m (10,500 and 12,500 ft) of elevation. A small body of permafrost , less than 25 m (80 ft) across, was found at the summit of Mauna Kea before 1974, and may still be present. Small gullies etch the summit, formed by rain- and snow-fed streams that flow only during winter melt and rain showers. On the windward side of

7080-436: The governing body in charge of conservation and land use management, changed its policy to a sustained-control program designed to facilitate the sport. Mouflon ( Ovis aries orientalis ) was introduced from 1962 to 1964, and a plan to release axis deer ( Axis axis ) in 1964 was prevented only by protests from the ranching industry, who said that they would damage crops and spread disease. The hunting industry fought back, and

7200-461: The gradual build-up of edifices that can reach extremely large dimensions. With the exclusion of flood basalts, mature shields are the largest volcanic features on Earth. The summit of the largest subaerial volcano in the world, Mauna Loa , lies 4,169 m (13,678 ft) above sea level , and the volcano, over 60 mi (100 km) wide at its base, is estimated to contain about 80,000 km (19,000 cu mi) of basalt. The mass of

7320-439: The ground, and gives the area a very low water retention capacity . Plant species found at this elevation include Styphelia tameiameiae , Taraxacum officinale , Tetramolopium humile , Agrostis sandwicensis , Anthoxanthum odoratum , Trisetum glomeratum , Poa annua , Sonchus oleraceus , and Coprosma ernodiodes . One notable species is Mauna Kea silversword ( Argyroxiphium sandwicense var. sandwicense ),

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7440-465: The houses on the island were built of koa, and those parts of the forest that survived became a source for firewood to power boilers on the sugarcane plantations and to heat homes. The once vast forest had almost disappeared by 1880, and by 1900, logging interests had shifted to Kona and the island of Maui . With the collapse of the sugar industry in the 1990s, much of this land lies fallow but portions are used for cattle grazing, small-scale farming and

7560-514: The island, whereas the number of native species is estimated at just 1,000. The summit of Mauna Kea lies above the tree line , and consists of mostly lava rock and alpine tundra . An area of heavy snowfall, it is inhospitable to vegetation, and is known as the Hawaiian tropical high shrublands . Growth is restricted here by extremely cold temperatures, a short growing season, low rainfall, and snow during winter months. A lack of soil also retards root growth, makes it difficult to absorb nutrients from

7680-400: The island. With an additional land grant in 1845, Parker established Parker Ranch on the northern slope of Mauna Kea, a large cattle ranch that is still in operation today. Settlers to the island burned and cut down much of the lower native forest for sugarcane plantations and houses. The Saddle Road , named for its crossing of the saddle-shaped plateau between Mauna Kea and Mauna Loa,

7800-592: The largest active volcanoes on Earth, such as Mauna Loa . Giant shield volcanoes are found on other planets of the Solar System , including Olympus Mons on Mars and Sapas Mons on Venus . The term 'shield volcano' is taken from the German term Schildvulkan , coined by the Austrian geologist Eduard Suess in 1888 and which had been calqued into English by 1910. Shield volcanoes are distinguished from

7920-439: The late 18th century, settlers introduced cattle, sheep, and game animals, many of which became feral and began to damage the volcano's ecological balance. Mauna Kea can be ecologically divided into three sections: an alpine climate at its summit, a Sophora chrysophylla – Myoporum sandwicense (or māmane–naio) forest on its flanks, and an Acacia koa – Metrosideros polymorpha (or koa–ʻōhiʻa) forest, now mostly cleared by

8040-452: The late 1920s, and continued through to 1949. One of the results of this grazing was the increased prevalence of herbaceous and woody plants, both endemic and introduced, that were resistant to browsing. The feral animals were almost eradicated, and numbered a few hundred in the 1950s. However, an influx of local hunters led to the feral species being valued as game animals , and in 1959 the Hawaiʻi Department of Land and Natural Resources ,

8160-641: The lava or shear stress on the part of local topography can morph a pāhoehoe flow into an ʻaʻā one, but the reverse never occurs. Although most shield volcanoes are by volume almost entirely Hawaiian and basaltic in origin, they are rarely exclusively so. Some volcanoes, such as Mount Wrangell in Alaska and Cofre de Perote in Mexico, exhibit large enough swings in their historical magmatic eruptive characteristics to cast strict categorical assignment in doubt; one geological study of de Perote went so far as to suggest

8280-778: The most prominent ones are situated along the Snake River in Idaho and the Columbia River in Washington and Oregon, where they have been measured to be over 1 mi (2 km) in thickness. Calderas are a common feature on shield volcanoes. They are formed and reformed over the volcano's lifespan. Long eruptive periods form cinder cones, which then collapse over time to form calderas. The calderas are often filled up by progressive eruptions, or formed elsewhere, and this cycle of collapse and regeneration takes place throughout

8400-406: The mountain exist to this day. However, very few natives reached the summit, because of the strict kapu placed on it. In the early 19th century, the earliest notable recorded ascents of Mauna Kea included the following: In the late 19th and early 20th centuries trails were formed, often by the movement of game herds, that could be traveled on horseback. However, vehicular access to the summit

8520-486: The māmane-naio ecosystem. There are many other species and ecosystems on the island, and on Mauna Kea, that remain threatened by human development and invasive species. The Mauna Kea Forest Reserve protects 52,500 acres (212 km) of māmane-naio forest under the jurisdiction of the Hawaii Department of Land and Natural Resources. Ungulate hunting is allowed year-round. A small part of the māmane–naio forest

8640-516: The natives wood for canoes and ornate bird feathers for decoration. There are three accounts of foreigners visiting Hawaiʻi before the arrival of James Cook , in 1778. However, the earliest Western depictions of the isle, including Mauna Kea, were created by explorers in the late 18th and early 19th centuries. Contact with Europe and America had major consequences for island residents. Native Hawaiians were devastated by introduced diseases; port cities including Hilo , Kealakekua , and Kailua grew with

8760-446: The northwest, and intersects the base of Mauna Loa to the south. The original eruptive fissures ( rift zones ) in the flanks of Mauna Kea were buried by its post-shield volcanism. Hilo Ridge, a prominent underwater rift zone structure east of Mauna Kea, was once believed to be a part of the volcano; however, it is now understood to be a rift zone of Kohala that has been affected by younger Mauna Kea flows. The shield-stage lavas that built

8880-441: The peak itself, reflecting the independence of the peak. Most sources (and the table below) define no parent for island and landmass highpoints; others treat Mount Everest as the parent of every such peak with the world ocean as the "key col". Download coordinates as: The following table lists the Earth's 125 most topographically prominent summits. Of these, Indonesia has the most, with 13. Close behind it are China and

9000-424: The permeability of the lake bed. No artesian water was known on the island of Hawaiʻi until 1993 when drilling by the University of Hawaiʻi tapped an artesian aquifer more than 300 m (980 ft) below sea level, that extended more than 100 m (330 ft) of the borehole 's total depth. The borehole had drilled through a compacted layer of soil and lava where the flows of Mauna Loa had encroached upon

9120-549: The picritic shields. They do not follow the pattern of caldera growth and destruction that other shield volcanoes do; caldera may form, but they generally do not disappear. Bingöl Mountains are one of the shield volcanoes in Turkey . In East Africa, volcanic activity is generated by the development of the East African Rift and from nearby hotspots. Some volcanoes interact with both. Shield volcanoes are found near

9240-680: The plan was put into action. While the land was partitioned no money was allocated for the building of the fence. In the midst of this wrangling the Endangered Species Act was passed; the National Audubon Society and Sierra Club Legal Defense Fund filed a lawsuit against the Hawaiʻi Department of Land and Natural Resources , claiming that they were violating federal law, in the landmark case Palila v. Hawaii Department of Land and Natural Resources (1978). The court ruled in favor of conservationists and upheld

9360-463: The planet's mantle for much, if not all of the Cenozoic Era. However, while Hawaiian volcanism is well understood and extensively studied, there remains no definite explanation of the mechanism that causes the hotspot effect. Lava flows from Mauna Kea overlapped in complex layers with those of its neighbors during its growth. Most prominently, Mauna Kea is built upon older flows from Kohala to

9480-527: The post-shield Laupāhoehoe Volcanics , erupted between 65,000 and 4,000 years ago. These changes in lava composition accompanied the slow reduction of the supply of magma to the summit, which led to weaker eruptions that then gave way to isolated episodes associated with volcanic dormancy. The Laupāhoehoe lavas are more viscous and contain more volatiles than the earlier tholeiitic basalts; their thicker flows significantly steepened Mauna Kea's flanks. In addition, explosive eruptions have built cinder cones near

9600-524: The precedence of federal laws before state control of wildlife. Having violated the Endangered Species Act, Hawaiʻi state was required to remove all feral animals from the mountainside. This decision was followed by a second court order in 1981. A public hunting program removed many of the feral animals, at least temporarily. An active control program is in place, though it is not conducted with sufficient rigor to allow significant recovery of

9720-462: The prevailing trade winds . Mauna Kea last erupted 6,000 to 4,000 years ago and is now thought to be dormant . In Hawaiian religion , the peaks of the island of Hawaiʻi are sacred. An ancient law allowed only high-ranking aliʻi to visit its peak. Ancient Hawaiians living on the slopes of Mauna Kea relied on its extensive forests for food, and quarried the dense volcano-glacial basalts on its flanks for tool production . When Europeans arrived in

9840-550: The prevailing cause of forest ecosystem collapse and avian extinction on Hawaiʻi appears to have been the introduction of the Polynesian (or Pacific) rat . The five volcanoes of Hawaiʻi are revered as sacred mountains ; and Mauna Kea's summit, the highest, is the most sacred. For this reason, a kapu (ancient Hawaiian law) restricted visitor rights to high-ranking aliʻi. Hawaiians associated elements of their natural environment with particular deities. In Hawaiian mythology ,

9960-665: The product of gentle effusive eruptions of highly fluid lavas that produce, over time, a broad, gently sloped eponymous "shield". Although the term is generally applied to basaltic shields, it has also at times been applied to rarer scutiform volcanoes of differing magmatic composition—principally pyroclastic shields , formed by the accumulation of fragmentary material from particularly powerful explosive eruptions, and rarer felsic lava shields formed by unusually fluid felsic magmas. Examples of pyroclastic shields include Billy Mitchell volcano in Papua New Guinea and

10080-406: The quick cooling of lava flows meeting glacial ice during subglacial eruptions ) to make tools. Volcanic glass and gabbro were collected for blades and fishing gear, and māmane wood was preferred for the handles. At peak quarry activity after AD 1400, there were separate facilities for rough and fine cutting; shelters with food, water, and wood to sustain the workers; and workshops creating

10200-506: The rift and off the coast of Africa, although stratovolcanoes are more common. Although sparsely studied, the fact that all of its volcanoes are of Holocene age reflects how young the volcanic center is. One interesting characteristic of East African volcanism is a penchant for the formation of lava lakes ; these semi-permanent lava bodies, extremely rare elsewhere, form in about 9% of African eruptions. The most active shield volcano in Africa

10320-570: The same volcanic "line" associated with most hotspots. They are not alone in this regard; the Cobb–Eickelberg Seamount chain in the North Pacific is another example of such a delineated chain. In addition, there is no clear pattern of age between the volcanoes, suggesting a complicated, irregular pattern of creation. How the islands were formed remains a geological mystery, although several theories have been proposed. Located over

10440-424: The seafloor. The Hawaiian and Galápagos shields, and other hotspot shields like them, are constructed of oceanic island basalt. Their lavas are characterized by high levels of sodium , potassium , and aluminium . Features common in shield volcanism include lava tubes . Lava tubes are cave-like volcanic straights formed by the hardening of overlaying lava. These structures help further the propagation of lava, as

10560-556: The shores, where food and water were plentiful. Settlement expanded inland to the Mauna Loa – Mauna Kea region in the 12th and early 13th centuries. Archaeological evidence suggests that these regions were used for hunting, collecting stone material, and possibly for spiritual reasons or for astronomical or navigational observations. The mountain's plentiful forest provided plants and animals for food and raw materials for shelter. Flightless birds that had previously known no predators became

10680-530: The site of an extensive replanting campaign since 1989. Parts of the reserve show the effect of agriculture on the native ecosystem, as much of the land in the upper part of the reserve is abandoned farmland. Bird species native to the acacia koa–ʻōhiʻa forest include the Hawaiian crow ( Corvus hawaiiensis ), the ʻakepa ( Loxops coccineus ), Hawaii creeper ( Oreomystis mana ), ʻakiapōlāʻau ( Hemignathus munroi ), and Hawaiian hawk ( Buteo solitarius ), all of which are endangered, threatened, or near threatened;

10800-402: The site of one of the longest-lasting rift eruptions in known history. The Hawaiian shield volcanoes are not located near any plate boundaries ; the volcanic activity of this island chain is distributed by the movement of the oceanic plate over an upwelling of magma known as a hotspot . Over millions of years, the tectonic movement that moves continents also creates long volcanic trails across

10920-483: The sites, most of which lie within what is now the Mauna Kea Ice Age Reserve . This early era was followed by cultural expansion between the 12th and late 18th century. Land was divided into regions designed for the immediate needs of the populace. These ahupuaʻa generally took the form of long strips of land oriented from the mountain summits to the coast. Mauna Kea's summit was encompassed in

11040-473: The solar system. Venus has over 150 shield volcanoes which are much flatter, with a larger surface area than those found on Earth, some having a diameter of more than 700 km (430 mi). Although the majority of these are long extinct it has been suggested, from observations by the Venus Express spacecraft , that many may still be active. List of mountain peaks by prominence This

11160-414: The summit of Mauna Kea was seen as the "region of the gods", a place where benevolent spirits reside. Poliʻahu , deity of snow, also resides there. "Mauna Kea" is an abbreviation for Mauna a Wākea and means "white mountain," in reference to its seasonally snow-capped summit. Around AD 1100, natives established adze quarries high up on Mauna Kea to extract the uniquely dense basalt (generated by

11280-495: The summit vents. In height they are typically about one twentieth their width. Although the general form of a "typical" shield volcano varies little worldwide, there are regional differences in their size and morphological characteristics. Typical shield volcanoes found in California and Oregon measure 3 to 4 mi (5 to 6 km) in diameter and 1,500 to 2,000 ft (500 to 600 m) in height, while shield volcanoes in

11400-407: The summit's outstanding suitability. An intense three-way competition for NASA funds to construct a large telescope began between Kuiper, Harvard University , and the University of Hawaiʻi (UH), which only had experience in solar astronomy. This culminated in funds being awarded to the "upstart" UH proposal. UH rebuilt its small astronomy department into a new Institute for Astronomy , and in 1968

11520-450: The summit. These cones are the most recent eruptive centers of Mauna Kea. Its present summit is dominated by lava domes and cinder cones up to 1.5 km (0.9 mi) in diameter and hundreds of meters tall. Mauna Kea is the only Hawaiian volcano with distinct evidence of glaciation . Similar deposits probably existed on Mauna Loa, but have been covered by later lava flows. Despite Hawaii's tropical location, during several past ice ages

11640-971: The surface wells up), such as the Hawaiian–Emperor seamount chain and the Galápagos Islands , or over more conventional rift zones, such as the Icelandic shields and the shield volcanoes of East Africa. Although shield volcanoes are not usually associated with subduction , they can occur over subduction zones. Many examples are found in California and Oregon, including Prospect Peak in Lassen Volcanic National Park , as well as Pelican Butte and Belknap Crater in Oregon. Many shield volcanoes are found in ocean basins , such as Kīlauea in Hawaii, although they can be found inland as well—East Africa being one example of this. The largest and most prominent shield volcano chain in

11760-582: The surrounding area; the darkness level allows the observation of faint astronomical objects . These factors historically made Mauna Kea an excellent spot for stargazing. In the early 1960s, the Hawaiʻi Island Chamber of Commerce encouraged astronomical development of Mauna Kea, as economic stimulus; this coincided with University of Arizona astronomer Gerard Kuiper 's search for sites to use newly improved detectors of infrared light . Site testing by Kuiper's assistant Alika Herring in 1964 confirmed

11880-440: The surrounding heat, and hit the ground still hot, accumulating into spatter cones . If eruptive rates are high enough, they may even form splatter-fed lava flows. Hawaiian eruptions are often extremely long-lived; Puʻu ʻŌʻō , a cinder cone of Kīlauea , erupted continuously from January 3, 1983, until April 2018. Flows from Hawaiian eruptions can be divided into two types by their structural characteristics: pāhoehoe lava which

12000-548: The tallest mountain in the world, from its underwater base. Mauna Kea is ranked 8th by topographic isolation . It is about one million years old and thus passed the most active shield stage of life hundreds of thousands of years ago. In its current post-shield state, its lava is more viscous , resulting in a steeper profile. Late volcanism has also given it a much rougher appearance than its neighboring volcanoes due to construction of cinder cones , decentralization of its rift zones , glaciation on its peak, and weathering by

12120-420: The term "compound shield-like volcano" instead. Most mature shield volcanoes have multiple cinder cones on their flanks, the results of tephra ejections common during incessant activity and markers of currently and formerly active sites on the volcano. An example of these parasitic cones is at Puʻu ʻŌʻō on Kīlauea —continuous activity ongoing since 1983 has built up a 2,290 ft (698 m) tall cone at

12240-425: The three other major volcanic types— stratovolcanoes , lava domes , and cinder cones —by their structural form, a consequence of their particular magmatic composition. Of these four forms, shield volcanoes erupt the least viscous lavas. Whereas stratovolcanoes and lava domes are the product of highly viscous flows, and cinder cones are constructed of explosively eruptive tephra , shield volcanoes are

12360-679: The tremendously deep roots of the Himalayan Mountains . Greater rises could be measured from the Atacama Trench to the Andes Mountains , for example, the bottom of Richard's Deep (8,065 m (26,460 ft) deep) to the peak of the nearby Llullaillaco (6,739 m (22,110 ft) high) is 14,804 m (48,570 ft). Neither Mount Lamlam nor Llullaillaco have the dry prominence of Mauna Kea, because they do not extend into trenches in every direction. Mauna Kea

12480-400: The volcano is so great that it has slumped the crust beneath it a further 8 km (5 mi). Accounting for this subsidence and for the height of the volcano above the sea floor , the "true" height of Mauna Loa from the start of its eruptive history is about 17,170 m (56,000 ft). Mount Everest , by comparison, is 8,848 m (29,029 ft) in height. In 2013, a team led by

12600-433: The volcano may be because they were reserved for burial. In pre-contact times, natives traveling up Mauna Kea were probably guided more by landscape than by existing trails, as no evidence of trails has been found. It is possible that natural ridges and water sources were followed instead. Individuals likely took trips up Mauna Kea's slopes to visit family-maintained shrines near its summit, and traditions related to ascending

12720-472: The volcano's lifespan. Interactions between water and lava at shield volcanoes can cause some eruptions to become hydrovolcanic . These explosive eruptions are drastically different from the usual shield volcanic activity and are especially prevalent at the waterbound volcanoes of the Hawaiian Isles . Shield volcanoes are found worldwide. They can form over hotspots (points where magma from below

12840-442: The volcano's rift zones. Central-vent eruptions, meanwhile, often take the form of large lava fountains (both continuous and sporadic), which can reach heights of hundreds of meters or more. The particles from lava fountains usually cool in the air before hitting the ground, resulting in the accumulation of cindery scoria fragments; however, when the air is especially thick with pyroclasts , they cannot cool off fast enough because of

12960-411: The volcano's upper flanks is ongoing. It has been suggested that the shrines, which are arranged around the volcano's summit along what may be an ancient snow line , are markers for the transition to the sacred part of Mauna Kea. Despite many references to burial around Mauna Kea in Hawaiian oral history, few sites have been confirmed. The lack of shrines or other artifacts on the many cinder cones dotting

13080-536: The volcano, stream erosion driven by trade winds has accelerated erosion in a manner similar to that on older Kohala. Mauna Kea is home to Lake Waiau , the highest lake in the Pacific Basin . At an altitude of 3,969 m (13,022 ft), it lies within the Puʻu Waiau cinder cone and is the only alpine lake in Hawaii. The lake is very small and shallow, with a surface area of 0.73 ha (1.80 acres) and

13200-440: The volcano, at an elevation of 2,000–3,000 m (6,600–9,800 ft), is dominated by māmane ( Sophora chrysophylla ) and naio ( Myoporum sandwicense ), both endemic tree species, and is thus known as māmane–naio forest. Māmane seeds and naio fruit are the chief foods of the birds in this zone, especially the palila ( Loxioides bailleui ). The palila was formerly found on the slopes of Mauna Kea, Mauna Loa, and Hualālai , but

13320-433: The volcanoes of Hawaiʻi Island , by far the most intensively studied of all shields because of their scientific accessibility; the island lends its name to the slow-moving, effusive eruptions typical of shield volcanism, known as Hawaiian eruptions . These eruptions, the least explosive of volcanic events, are characterized by the effusive emission of highly fluid basaltic lavas with low gaseous content . These lavas travel

13440-534: The walls of the tube insulate the lava within. Lava tubes can account for a large portion of shield volcano activity; for example, an estimated 58% of the lava forming Kīlauea comes from lava tubes. In some shield volcano eruptions, basaltic lava pours out of a long fissure instead of a central vent, and shrouds the countryside with a long band of volcanic material in the form of a broad plateau . Plateaus of this type exist in Iceland, Washington, Oregon, and Idaho;

13560-472: The welfare of the species began in 1980. The closely related Nysius aa lives on Mauna Loa. Wolf spiders (Lycosidae) and forest tent caterpillar moths have also been observed in the same Mauna Kea ecosystem; the former survive by hiding under heat-absorbing rocks, and the latter through cold-resistant chemicals in their bodies. Several native moths are also present near the summit including Agrotis helela and Agrotis kuamauna . The forested zone on

13680-724: The world is the Hawaiian–Emperor seamount chain, a chain of hotspot volcanoes in the Pacific Ocean. The volcanoes follow a distinct evolutionary pattern of growth and death. The chain contains at least 43 major volcanoes, and Meiji Seamount at its terminus near the Kuril–Kamchatka Trench is 85 million years old. The youngest part of the chain is Hawaii, where the volcanoes are characterized by frequent rift eruptions, their large size (thousands of km in volume), and their rough, decentralized shape. Rift zones are

13800-686: The world with a permanent lava lake, which has been active since at least 1967, and possibly since 1906. Other volcanic centers include Menengai , a massive shield caldera, and Mount Marsabit in Kenya. Shield volcanoes are not limited to Earth; they have been found on Mars , Venus , and Jupiter's moon, Io . The shield volcanoes of Mars are very similar to the shield volcanoes on Earth. On both planets, they have gently sloping flanks, collapse craters along their central structure, and are built of highly fluid lavas. Volcanic features on Mars were observed long before they were first studied in detail during

13920-428: Was about 4,600 years ago (about 2600 BC); because of this inactivity, Mauna Kea is assigned a United States Geological Survey hazard listing of 7 for its summit and 8 for its lower flanks, out of the lowest possible hazard rating of 9 (which is given to the extinct volcano Kohala ). Since 8000 BC lava flows have covered 20% of the volcano's summit and virtually none of its flanks. Despite its dormancy, Mauna Kea

14040-500: Was completed in 1943, and eased travel to Mauna Kea considerably. The Pohakuloa Training Area on the plateau is the largest military training ground in Hawaiʻi. The 108,863-acre (44,055 ha) base extends from the volcano's lower flanks to 2,070 m (6,790 ft) elevation, on state land leased to the US Army since 1956. There are 15 threatened and endangered plants, three endangered birds, and one endangered bat species in

14160-424: Was established in 1981. The reserve is a region of sparsely vegetated cinder deposits and lava rock, including areas of aeolian desert and Lake Waiau. This ecosystem is a likely haven for the threatened ʻuaʻu ( Pterodroma sandwichensis ) and also the center of a study on wēkiu bugs ( Nysius wekiuicola ). Wēkiu bugs feed on dead insect carcasses that drift up Mauna Kea on the wind and settle on snow banks. This

14280-430: Was further revised to address concern expressed in the Hawaiian community that a lack of respect was being shown toward the cultural values of the mountain. Shield volcano Shield volcanoes are found wherever fluid, low- silica lava reaches the surface of a rocky planet. However, they are most characteristic of ocean island volcanism associated with hot spots or with continental rift volcanism. They include

14400-646: Was practically impossible until the construction of a road in 1964, and it continues to be restricted. Today, multiple trails to the summit exist, in various states of use. Hawaiʻi's geographical isolation strongly influences its ecology. Remote islands like Hawaiʻi have a large number of species that are found nowhere else (see Endemism in the Hawaiian Islands ). The remoteness resulted in evolutionary lines distinct from those elsewhere and isolated these endemic species from external biotic influence, and also makes them especially vulnerable to extinction and

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