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Socorro Island ((スペイン語:Isla Socorro)) is a small volcanic island in the Revillagigedo Islands, a Mexican possession lying some 600 kilometers off the country's western coast at 18°48'N, 110°59'W. The size is 16.5 by 11.5 km, with an area of 132 km2. It is the largest of the four islands of the Revillagigedo Archipelago. == Geology == The island rises abruptly from the sea to in elevation at its summit. Isla Socorro is a shield volcano. The island is part of the northern Mathematicians Ridge, a mid-ocean ridge that became largely inactive 3.5 million years ago when activity moved to the East Pacific Rise. All four islands along with the many seamounts on the ridge are post-abandonment alkaline volcanoes. Socorro Island is unusual in that it is the only dominantly silicic peralkaline volcanic island in the Pacific Ocean. It most recently erupted in late January-early February, 1993, which was a submarine flank eruption off the coast from Punta Tosca. An earlier eruption was on May 21, 1951; earlier eruptions probably occurred in 1905, 1896 and 1848. The initial volcanic event probably occurred in 3090 BC +/- 500 years.〔(Global Volcanism Program | Socorro | Eruptive History ). Volcano.si.edu. Retrieved on 2013-03-31.〕 Mount Evermann (Spanish: ''Cerro Evermann'') is the name given to the summit dome complex, in honor of ichthyologist Barton Warren Evermann. The island's surface is broken by furrows, small craters, and numerous ravines, and covered in lava domes, lava flows and cinder cones.〔 There is a naval station , established in 1957, with a population of 250 (staff and families), living in a village with a church, that stands on the western side of Bahia Vargas Lozano, a small cove with a rocky beach, about 800 meters east of Cabo Regla, the southernmost point of the island. The station is served by a dock, a local helipad and airport ''Isla Socorro'', located six kilometers to the north, at . There is a freshwater spring about 5 km northwest of Cabo Regla, at the shoreline of Ensenada Grayson (or Caleta Grayson), an inlet. This is brackish or even covered by the sea at high tide. Apart from some temporary pools and maybe one that is more permanent, a small freshwater seep exists most of the time some inland at Bahia Lucio Gallardo Pavon (Binner's Cove), 800 meters NW of the naval station.〔 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「Socorro Island」の詳細全文を読む スポンサード リンク
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