Mauna Kea typically is a volcano on the island of Hawaii. Standing four,205 m (13,796 ft) above sea level, its peak is the actual highest point within the state of Hawaii. Though, a great deal of the mountain is actually below water; whenever calculated from its oceanic base, Mauna Kea typically is over 10,200 m (33,500 ft) tall-significantly taller than Mount Everest typically is above sea level. Mauna Kea is regarding a million years of age, and even has thereby passed the most active protect stage of everyday living hundreds of thousands of years ago. With regard to its current post-shield state, its lava is a bit more viscous, causing a steeper profile. Late volcanism has also given it a much rougher appearance than its neighboring volcanoes; contributing aspects consist of the construction of cinder cones, the actual decentralization of its rift zones, the particular glaciation on its peak, plus the weathering effects associated with the prevailing trade winds. Mauna Kea previous erupted 4,000 to 6,000 years ago. According to the USGS, as of January 2012, the particular Volcanic-Alert Degree is actually “Normal”.
Throughout Hawaiian mythology, the particular peaks associated with the island of Hawaii are sacred, and also Mauna Kea is the many sacred of all the. A great ancient law allowed just high-ranking tribal chiefs to visit its peak. Ancient Hawaiians living on the slopes of Mauna Kea relied on its extensive forests for food, and additionally quarried the particular thick volcano-glacial basalts on its flanks for tool production. Whenever Europeans arrived within the late 18th century, settlers introduced cattle, sheep and game animals, several of which was feral and even began to be able to damage the actual mountain’s ecology. Mauna Kea is ecologically separated into 3 sections: a great alpine climate at its summit, a Sophora chrysophylla-Myoporum sandwicense (or simply mamane-naio) woodland about its flanks, and also a particular Acacia koa-Metrosideros polymorpha (and / or koa-?ohi?a) woodland, at this point mostly cleared by the actual former sugar industry, at its base. In recent many years, concern over the particular vulnerability of the native species has led to court situations which currently have forced the actual Hawaii Department of Land plus All-natural Resources to be able to eradicate just about all feral species about the mountain.
Alongside its significant altitude, dry environment, plus stable airflow, Mauna Kea’s summit is regarded as the actual best sites within the world for astronomical observation, and also one of several most controversial. Because the particular creation of a great access road throughout 1964, thirteen telescopes funded by eleven nations have been designed at the particular summit. The actual Mauna Kea Observatories are used for scientific analysis over the particular electromagnetic spectrum from visible light in order to radio, as well as include the biggest such facility in the globe. Their construction on a “sacred landscape”, replete alongside endangered varieties plus ongoing cultural practices, has been a topic of debate and in addition protest. Research are really underway with determine their impact found on the summit ecology.
Mauna Kea is actually one of five hotspot volcanoes that form the actual island of Hawaii, the particular biggest plus youngest island of the Hawaiian-Emperor seamount chain. Of these five volcanoes, Mauna Kea is actually the actual 4th oldest not to mention fourth many active. It began as a preshield volcano driven by the Hawaii hotspot about 1 million years ago, as well as was extremely active during the course of its protect stage up until 500,000 years ago. Mauna Kea joined its quieter post-shield stage 250,000 to be able to 200,000 many years ago, not to mention typically is currently dormant.
Mauna Kea is actually over three,220 km3 (770 cu mi) throughout volume, so huge it and additionally its neighbor, Mauna Loa, depress the actual ocean crust beneath it by 6 km (4 mi). The actual volcano continues to slip and additionally flatten underneath its very own body weight at a rate of lower than 0.2 mm (0.01 in) per year. A lot of its mass lies east of its present summit. Mauna Kea stands four,205 m (13,800 ft) above sea level, only 35 m (110 ft) higher than its neighbor Mauna Loa. Measured from its base found on the ocean floor, it rises over 10,000 m (33,000 ft), significantly better than the elevation of Mount Everest above sea level, as well as typically is the particular highest point with regard to the state of Hawaii.
Such as all the Hawaiian volcanoes, Mauna Kea happens to be produced by the Hawaiian hotspot, because the particular Pacific tectonic plate has relocated over a hotspot inside the Earth’s fundamental mantle. The actual Hawaii island volcanoes tend to be just the latest evidence of this task which, over 70 million many years, has built the 6,000 km (3,700 mi)-long Hawaiian Ridge – Emperor Seamount chain. The actual prevailing, though not completely settled, see is actually that the hotspot has been largely stationary in the planet’s mantle for a great deal, if not all of the Cenozoic Era. Nevertheless, while Hawaiian volcanism is actually well-understood plus extensively studied, there remains no definite explanation associated with the mechanism which causes the hotspot impact.
Lava flows from Mauna Kea overlapped in complex layers with those of its neighbors throughout its growth. Most prominently, Mauna Kea is actually built on elder flows from Kohala in order to the northwest, as well as intersects the particular base of Mauna Loa to be able to the particular south. The original eruptive fissures (rift zones) within the flanks of Mauna Kea had been buried by its post-shield volcanism. Hilo Ridge, a prominent underwater rift zone structure east of Mauna Kea, was as soon as believed in order to be a piece associated with the volcano; still, it really is presently understood with be a rift zone of Kohala which has been affected by young Mauna Kea flows.
The particular shield-stage lavas that built the enormous leading mass associated with the mountain are generally tholeiitic basalts, like all those of Mauna Loa, built via the particular mixing of main magma as well as subducted oceanic crust. They are generally covered by the oldest exposed rock strata on Mauna Kea, the post-shield alkali basalts associated with the Hamakua Volcanics, which erupted between 250,000 plus 70-65,000 many years ago. The latest volcanic flows usually are hawaiites and mugearites: they tend to be the post-shield Laupahoehoe Volcanics, erupted between 65,000 not to mention four,000 years ago. Many of these changes in lava composition accompanied the particular slow reduction of the supply of magma with the summit, which led with weaker eruptions that consequently gave option to isolated episodes associated with volcanic dormancy. The Laupahoehoe lavas are far more viscous and even contain more volatiles compared to the actual earlier tholeiitic basalts; their thicker flows significantly steepened Mauna Kea’s flanks. In addition, explosive eruptions have built cinder cones close to the summit. Many of these cones usually are the latest eruptive centers of Mauna Kea. Its present summit is dominated by lava domes and cinder cones up to 1.5 km (0.9 mi) inside diameter and even hundreds of meters tall.
Scoria and cinder cones on Mauna Kea’s summit inside wintertime
Glacial evidence on Mauna Kea, outlining terminal moraines (“m”) and till (“w”)
Mauna Kea is actually the actual only Hawaiian volcano alongside distinct evidence of glaciation. Synonymous deposits most likely existed on Mauna Loa, however, come with been covered by later lava flows. Despite Hawaii’s tropical place, during the course of many past ice ages a drop of only a degree inside temperature enabled snow with stay at the particular mountain’s summit via summertime, triggering the particular formation of an ice cap. There are three shows of glaciation that have been recorded within the previous 180,000 years: the actual Pohakuloa (180-130 ka), Waihu (80-60 ka) plus Makanaka (40-13 ka) show. Many of these have extensively sculpted the summit, depositing moraines along with a circular ring of till and additionally gravel over the mountain’s upper flanks. Subglacial eruptions built cinder cones for the duration of the particular Makanaka glaciation, almost all of that were heavily gouged by glacial action. The actual many recent cones happened to be built between 9000 and even 4500 many years ago, atop the particular glacial deposits, though specific research indicates which the particular last eruption can come with been about 3600 many years ago.
At their maximum extent, the particular glaciers extended within the summit down to between three,200 and 3,800 m (10,500 and in addition 12,500 ft) of elevation.[23] A small human body of permafrost, not as much as 25 m (80 ft) across, was found at the particular summit of Mauna Kea before to 1974, plus could very well nevertheless be present. Little gullies etch the actual summit, created by rain- not to mention snow-fed streams which stream just during wintertime melt and additionally rain showers. About the windward side associated with the mountain, flow erosion driven by trade winds has accelerated erosion inside a way synonymous to this on more aged Kohala.
Mauna Kea is actually dwelling to be able to Lake Waiau, the particular highest lake within the Pacific Basin. At an altitude of three,969 m (13,022 ft), it lies in the Pu?u Waiau cinder cone and additionally is actually truly the only alpine lake with regard to Hawaii. The particular lake is really small and also shallow, alongside a surface neighborhood of 0.73 ha (1.80 acres) and even a level of 3 m (10 ft). Radiocarbon dating of samples at the particular base associated with the lake indicates it was clear of ice 12,600 years ago. Hawaiian lavas usually are regularly permeable, preventing the actual formation of lakes due in order to infiltration. Here, either sulfur-bearing steam altered the actual volcanic ash in order to low-permeability clays, or explosive interactions between rising magma not to mention groundwater or simply surface water (phreatic eruptions) formed exceptionally fine ash which also would lower the permeability associated with the lake bed.

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