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Wolf Volcano is the highest peak in the Galapagos Islands and is situated on Isabela Island and reaches . It is a shield volcano with a characteristic upturned soup bowl shape. The volcano was named after Theodor Wolf, a German geologist who studied the Galapagos Islands in the 19th century. Wolf Island in the north of the Galapagos is also named after the geologist. Its height makes Wolf Volcano an "ultra prominent peak", which is a peak with a topographic prominence of over 1500m. == Geology == In a process similar to the formation of the Hawaiian islands, the Galapagos (along with associated hotspot) appear to be created from a mantle plume. This plume stays in place while the Nazca plate moves above it; the relative movement of this plate is 0.46 degrees per million years.〔 (deg/m.y. figure is on page 1110)〕 The volcano itself is estimated to be less than half a million years old; the oceanic plate beneath it is theorized to be around 10 million years old. Wolf is situated at the northern end of Isabela Island in the Galapagos, and sits on the Equator, one of six coalescing volcanoes that make up this island (the others being Ecuador, Darwin, Alcedo, Sierra Negra, and Cerro Azul). Along with the Fernandina Island volcano, the western Galapagos volcanoes have similar structures that differ from the volcanoes in the eastern part of the archipelago. The western volcanoes are higher and have larger calderas than those to the east, they are also shaped like an upturned soup bowl. Wolf reaches a height of over 1700 metres; the caldera is 6 by 7 km and has a depth of 700m. Only Cerro Azul has a caldera of similar depth in the Galapagos. Following the last eruption, there was collapse in the caldera, causing its stepped appearance. Wolf has very steep slopes reaching 35 degrees in places, making access difficult. The first historical eruption in the Galapagos was recorded for this volcano in 1797; a further ten eruptions have been recorded since then, the last being on May 25, 2015. Eruptions prior to 1797 have been dated from analysis of surface exposures. The newest lavas are on the eastern and southern sides as well as within the caldera. Lava flows from Wolf are unusual for a mid-ocean island and also differ from the two volcanoes next to it, Ecuador and Darwin and other volcanoes closer to the centre of the plume. The lavas from Wolf are similar to those erupted from the Galapagos Spreading Center, a mid-ocean ridge over 200 km away, which may be due to interaction between the plume, which is centred on Fernandina, and the upper mantle.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Volcán Wolf」の詳細全文を読む スポンサード リンク
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