Mauna Kea is a volcano found on the island of Hawaii. Standing 4,205 m (13,796 ft) above sea degree, its peak is the highest point within the state of Hawaii. Even so, much associated with the mountain typically is under water; whenever calculated from its oceanic base, Mauna Kea is over 10,200 m (33,500 ft) tall-significantly taller compared to Mount Everest is above sea degree. Mauna Kea is actually about a million many years old, and also has thus passed the actual most active protect stage of lifetime hundreds of thousands of many years ago. Within its active post-shield state, its lava is much more viscous, resulting in a steeper profile. Late volcanism has as well provided it a great deal rougher appearance compared to its neighboring volcanoes; contributing factors include the particular construction of cinder cones, the particular decentralization of its rift zones, the actual glaciation about its peak, plus the weathering effects of the prevailing trade winds. Mauna Kea endure erupted 4,000 to be able to 6,000 many years ago. Based on the USGS, because of January 2012, the Volcanic-Alert Level typically is “Normal”.
Inside Hawaiian mythology, the peaks of the island of Hawaii usually are sacred, not to mention Mauna Kea is actually the actual the majority of sacred of every. An historic law permitted just high-ranking tribal chiefs with check out its peak. Historic Hawaiians living found on the slopes of Mauna Kea relied on its extensive forests for food, plus quarried the dense volcano-glacial basalts about its flanks for tool creation. When 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 could be ecologically separated into three sections: a great alpine climate at its summit, a Sophora chrysophylla-Myoporum sandwicense (or simply mamane-naio) forest 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 found on the mountain.
Alongside its significant altitude, dry environment, plus stable airflow, Mauna Kea’s summit is actually one of the number one sites throughout the world for astronomical observation, and also the most controversial. Because the particular creation of a great access road within 1964, thirteen telescopes funded by eleven nations have been designed at the particular summit. The actual Mauna Kea Observatories are utilized for scientific research across the actual electromagnetic spectrum from visible light to be able to radio, and also include the largest such center within the world. Their construction on a “sacred landscape”, replete alongside endangered species as well as ongoing cultural practices, has been a topic of debate not to mention protest. Research are underway to determine their impact about the summit ecology.
Mauna Kea is regarded as five hotspot volcanoes that shape the actual island of Hawaii, the particular largest as well as youngest island associated with the Hawaiian-Emperor seamount chain. Of many of these five volcanoes, Mauna Kea is actually the actual fourth oldest and additionally fourth most 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 many 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 typically is over three,220 km3 (770 cu mi) throughout volume, so huge that it as well as its neighbor, Mauna Loa, depress the particular ocean crust underneath it by 6 km (4 mi). The particular volcano continues with slip not to mention flatten under its very own fat 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, simply just 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), greatly better than the elevation of Mount Everest above sea level, plus typically is the highest point within the state of Hawaii.
Such as every one of the Hawaiian volcanoes, Mauna Kea happens to be created by the Hawaiian hotspot, because the Pacific tectonic plate has moved over a hotspot in the Earth’s underlying mantle. The particular Hawaii island volcanoes happen to be simply the actual many recent evidence of the task that, over 70 million years, has built the actual 6,000 km (three,700 mi)-long Hawaiian Ridge – Emperor Seamount chain. The actual prevailing, though not completely settled, see is actually that the actual hotspot has become mostly stationary in the planet’s mantle for a great deal, in case not the Cenozoic Era. But bear in mind, while Hawaiian volcanism typically is well-understood not to mention extensively studied, there remains no definite explanation associated with the mechanism which causes the particular hotspot effect.
Lava flows from Mauna Kea overlapped inside complex layers alongside those of its neighbors in the course of its growth. Most prominently, Mauna Kea typically is built upon more aged flows from Kohala to be able to the particular northwest, and also intersects the actual base of Mauna Loa with the actual south. The authentic eruptive fissures (rift zones) throughout the flanks of Mauna Kea happened to be buried by its post-shield volcanism. Hilo Ridge, a prominent underwater rift zone structure east of Mauna Kea, was when believed with be a piece associated with the volcano; though, it happens to be at this point understood in order to be a rift zone of Kohala which has been affected by young Mauna Kea flows.
The shield-stage lavas that built the actual massive key mass associated with the mountain happen to be tholeiitic basalts, like those of Mauna Loa, created through the particular mixing of main magma and subducted oceanic crust. They usually are covered by the particular oldest exposed rock strata on Mauna Kea, the particular post-shield alkali basalts associated with the Hamakua Volcanics, that erupted between 250,000 and additionally 70-65,000 years ago. The particular most recent volcanic flows are really hawaiites and in addition mugearites: they are really the particular post-shield Laupahoehoe Volcanics, erupted between 65,000 and additionally four,000 years ago. Many of these changes inside lava composition accompanied the particular slow reduction of the provide of magma to the particular summit, which led to weaker eruptions that afterward gave means to isolated shows associated with volcanic dormancy. The Laupahoehoe lavas are really more viscous and in addition contain more volatiles compared to the earlier tholeiitic basalts; their thicker flows significantly steepened Mauna Kea’s flanks. Inside addition, explosive eruptions have built cinder cones near the summit. Many of these cones tend to be the particular the majority of recent eruptive centers of Mauna Kea. Its present summit is actually dominated by lava domes and in addition cinder cones about 1.5 km (0.9 mi) within diameter and in addition hundreds of meters tall.
Scoria and even cinder cones on Mauna Kea’s summit within wintertime
Glacial evidence on Mauna Kea, outlining terminal moraines (“m”) and in addition until (“w”)
Mauna Kea is actually truly the only Hawaiian volcano alongside distinct evidence of glaciation. Similar deposits possibly existed about Mauna Loa, nevertheless have been covered by later on lava flows. Despite Hawaii’s tropical place, during several previous ice ages a drop of just a degree within temperature granted snow to remain at the actual mountain’s summit through summertime, triggering the actual formation of a great ice cap. There are generally 3 episodes of glaciation that come with been recorded within the previous 180,000 years: the particular Pohakuloa (180-130 ka), Waihu (80-60 ka) and in addition Makanaka (40-13 ka) show. Many of these have extensively sculpted the summit, depositing moraines along with a circular ring of until and even gravel along the mountain’s upper flanks. Subglacial eruptions built cinder cones throughout the actual Makanaka glaciation, many of which happened to be heavily gouged by glacial action. The particular latest cones had been built between 9000 not to mention 4500 years ago, atop the actual glacial deposits, even though you study indicates that the endure eruption might have been around 3600 years ago.
At their maximum extent, the actual glaciers extended from the summit right down to between 3,220 plus three,800 m (10,500 and additionally 12,500 ft) of elevation.[23] A tiny human body of permafrost, lower than 25 m (80 ft) over, had been found at the actual summit of Mauna Kea before 1974, and additionally might possibly nevertheless be present. Tiny gullies etch the summit, formed by rain- and snow-fed streams that flow only in the course of wintertime melt as well as rain showers. Found on the windward side associated with the mountain, stream erosion driven by trade winds has fast erosion inside a manner similar to that on elder Kohala.
Mauna Kea is home to Lake Waiau, the actual highest lake with regard to the Pacific Basin. At a great altitude of 3,969 m (13,022 ft), it lies in the Pu?u Waiau cinder cone and even is the only alpine lake inside Hawaii. The actual lake is actually quite tiny and in addition shallow, alongside a surface community of 0.73 ha (1.80 acres) along with a depth of 3 m (10 ft). Radiocarbon dating of samples at the actual base of the lake indicates it had been well-defined of ice 12,600 many years ago. Hawaiian lavas are really usually permeable, preventing the actual formation of lakes due in order to infiltration. Here, either sulfur-bearing steam changed the volcanic ash in order to low-permeability clays, or simply explosive interactions between rising magma and additionally groundwater and / or surface water (phreatic eruptions) created extremely fine ash that as well might minimize the actual permeability associated with the lake bed.

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