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Alamagan is an island in the Northern Mariana Islands in the Pacific Ocean. The island is currently uninhabited. Alamagan is located north from Guguan and north from Saipan, and is south from Pagan. ==Geography== Alamagan is roughly elliptical in shape, with a length of and a width of and an area of .〔Brainard, ''(Coral reef ecosystem monitoring report )'', S. 1〕 The entire island is the summit of stratovolcano which rises over from the ocean floor, to an altitude of above sea level at its highest peak, Bandeera Peak, at the northwestern edge. The volcano is topped by a caldera, 700–900 meters in diameter with a depth of about deep. There are three smaller cones at the north, northwest and south of the main crater. The volcano has not erupted in historical times, but by radiocarbon dating, eruptions occurred in 540 AD and 870 AD, with a potential error in dating of around 100 years. These eruptions involved pyroclastic flows, and had a VEI of 4. Any claims of historical eruptions are inaccurate, though uncertain eruptions have occurred as late as 1887.〔http://www.volcano.si.edu/world/volcano.cfm?vnum=0804-18=&volpage=erupt〕 Within the main crater and on the western slopes are a number of active fumaroles. The island has extremely steep slopes on its eastern side which are prone to landslides. The western slope has deep canyons as the result of erosion. The shoreline is dominated by steep cliffs of up to in height on the eastern shore. Vegetation on the west side of the island includes Swordgrass ''(Miscanthus floridulus)'', whereas the southeast side is a steep slope of bare lava. There are deep valleys with caves. Coconut Palms ''(Cocos nucifera),'' grow on the gradual slopes. Warm fresh water springs are located on the northern part of the west coast. Alamagan is the home of the endangered Nightingale Reed Warbler, ''Acrocephalus luscinia'' which presently can be found only here, Saipan and possibly Aguijan. 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「Alamagan」の詳細全文を読む スポンサード リンク
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