what is the tallest volcano in hawaiian islands
Mauna Kea Mauna Kea (/ˌmɔːnə ˈkeɪ.ə/ or /ˌmaʊnə ˈkeɪ.ə/, Hawaiian: [ˈmɐwnə ˈkɛjə]), is a dormant volcano on the island of Hawaii. Standing 4,207 m (13,802 ft) above sea level, its peak is the highest point in the state of Hawaii making the island of Hawaii the second highest island in the world. Most of the mountain is underwater; when measured from its oceanic base, Mauna Kea is over 10,000 m (33,000 ft) tall and is the tallest mountain on Earth.[5] Mauna Kea is about a million years old, and has 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; contributing factors include the construction of cinder cones, the decentralization of its rift zones, the glaciation on its peak, and the weathering effects of the prevailing trade winds. Mauna Kea last erupted 6,000 to 4,000 years ago and is now considered dormant.
Mount Vesuvius Vesuvius has erupted many times since and is the only volcano on the European mainland to have erupted within the last hundred years. Today, it is regarded as one of the most dangerous volcanoes in the world because of the population of 3,000,000 people living nearby, making it the most densely populated volcanic region in the world, as well as its tendency towards violent, explosive eruptions of the Plinian type.[5]
Mount Mazama Mazama was last active about 4,800 years ago, when an eruption took place near Wizard Island's eastern base.[96] This eruption took place underwater,[93] and it produced viscous lava that created a rhyodacite lava dome, about 2,400 years after the first period of postcaldera activity.[97] Given that Mazama has had periods of sporadic eruptions for 420,000 years, the United States Geological Survey thinks that it is "virtually certain" that Mazama will erupt again in the future.[6][98] Mazama is considered dormant, but it remains monitored by the United States Geological Survey Cascades Volcano Observatory.[21] Future eruptions would likely take place near the western side of the complex and within the caldera rim; they could occur underwater. The ejection of lava rich in gas from shallow water could produce huge ash columns, but submarine eruptions at deeper depths may decrease the explosiveness of the event. Nonetheless, the rapid mixing of water and lava could produce dangerous pyroclastic surges, which are more gaseous and less solid than pyroclastic flows.[6] Such flows could pass over topographic barriers, move rock fragments at rapid speeds of 800 feet per second (240 m/s), and travel several miles from their vent.[99] Mazama is unlikely to produce mudflows far from the caldera, though a nearby vent outside the caldera could erupt and mix with snow. Eruptions are unlikely to produce waves that extend beyond Crater Lake, but powerful explosions could produce tall waves in the caldera.[100] An eruption as explosive as the one 7,700 years ago is unlikely given that it would require larger volumes of magma than are known to be available within the Mazama vicinity.[39] Moreover, landslides could flood adjacent shoreline regions, but they are not likely to induce failure of the caldera's walls, as they rise more than 500 feet (150 m) above the lake's surface.[39] Earthquakes from the nearby West Klamath Lake fault zone could reach magnitudes up to 7.0 on the Richter scale, but these only occur every 3,000 to 10,000 years; they could generate tall waves by creating landslides.[39] Though local earthquakes from volcanic activity would create motion in the lake, they would likely only reach maximum magnitudes of 5.0 on the Richter scale. However, Crater Lake is poorly monitored, and not highly active seismically among the Cascade volcanoes.[101] The largest earthquake threat originates from the Cascadia subduction zone, which could produce earthquakes with a magnitude of 8 or 9 that could lead to huge waves in Crater Lake.[32]
Hawaii hotspot The Hawaii hotspot is a volcanic hotspot located near the namesake Hawaiian Islands, in the northern Pacific Ocean. One of the most well-known and heavily studied hotspots in the world,[1][2] the Hawaii plume is responsible for the creation of the Hawaiian – Emperor seamount chain, a chain of volcanoes over 5,800 kilometres (3,600 mi) long. Four of these volcanoes are active, two are dormant, and more than 123 are extinct, many having since been ground beneath the waves by erosion as seamounts and atolls. The chain extends from south of the island of Hawaiʻi to the edge of the Aleutian Trench, near the eastern edge of Russia. While most volcanoes are created by geological activity at tectonic plate boundaries, the Hawaii hotspot is located far from plate boundaries. The classic hotspot theory, first proposed in 1963 by John Tuzo Wilson, proposes that a single, fixed mantle plume builds volcanoes that then, cut off from their source by the movement of the Pacific Plate, become increasingly inactive and eventually erode below sea level over millions of years. According to this theory, the nearly 60° bend where the Emperor and Hawaiian segments of the chain meet was caused by a sudden shift in the movement of the Pacific Plate. In 2003, fresh investigations of this irregularity led to the proposal of a mobile hotspot theory, suggesting that hotspots are mobile, not fixed, and that the 47-million-year-old bend was caused by a shift in the hotspot's motion rather than the plate's.