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308:(Mita, 1949). As a result of the survey, however, the authors found that both Myōjin-shō and the Bayonnaise Rocks are cones on the somma of a double volcano. The foot of this double volcano lies 1,400 to 1,500 meters in depth and the size is about 30 by 25 kilometers east-west, north-south. The somma is almost a circle in the diameter of 7 by 9 kilometers and the height is 1,000 – 1,400meters.
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Myōjin-shō is a post caldera cone formed in the northeastern part of the somma of the double volcano. It is a single conical cone and its height is 550 meters with the shallowest depth 50 meters. A record that suggests a gushing of bubbles near the summit was obtained and micro-earthquakes
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The volcanic eruption from 1952 to 1953 was one of its biggest eruptions on record, with the repetitious appearance and disappearance of an island, which at one point reached over ten metres above sea level, before sinking after a major volcanic eruption in
September 1953. On September 24, 1952, a
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Department of the
Maritime Safety Agency, was destroyed by the volcano, with the loss of its crew of 31 (including the nine scientists studying the eruption). Consequently, the Department developed
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conducted the survey of the sea area within a radius of about 10 nautical miles (about 18.5 kilometers) but farther than the area of the radius of 3 nautical miles (5.6 km).
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In 1998 and 1999, the
Hydrography Department conducted comprehensive sea bottom surveys around Myōjin-shō, using the state-of-the-art survey vessel
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The diameter of the caldera floor is 5.6 kilometers and about 1,100 meters in depth. The central cone is a high formerly known as
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Steam pours from the blocky summit of a lava dome formed at Myōjin-shō during a submarine eruption at the
Bayonnaise Rocks volcano in 1952.
231:(Sunfish), an unmanned radio operating survey boat, and has used it for the research of dangerous sea areas such as submarine volcanoes.
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conducted a comprehensive survey including the geological and geophysical surveys of sea bottom. Bathymetric survey of
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was carried out by using a "Seabeam 2112" echo sounder at intervals of 0.5 nautical miles (about 930 meters).
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works by the order of preprogrammed instructions and measures depth and water temperature. Bathymetric survey of
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was carried out by using the "PRD-601" echo sounder at intervals of 0.2 nautical miles (about 370 meters).
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A mysterious reef raised a volcanic plume and "Chihuri-class patrol vessel" sailors looked at it (1952)
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were observed near Myōjin-shō, showing that the volcano is still active, although at a low level
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Previously, Myōjin-shō was considered to be the central cone of a double volcano with the
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This was the first time that volcanic activity had been detected using the
451:"Transpacific detection of Myojin volcanic explosions by underwater sound"
404:"Transpacific Detection of Myojin Volcanic Explosions by Underwater Sound"
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Submarine volcano south of Tokyo on the Izu-Ogasawara Ridge
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conducted the survey of the sea area within a radius of 3
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10.1130/0016-7606(1954)65[941:TDOMVE]2.0.CO;2
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188:The name Myōjin-shō derives from a fishing boat,
262:around Myōjin-shō was made for the first time.
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510:Former islands from the last glacial maximum
272:(about 5.4 kilometers) of Myōjin-shō.
169:located about 450 kilometers south of
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408:Geological Society of America Bulletin
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402:Dietz, R. S.; Sheehy, M. J. (1954).
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173:on the Izu-Ogasawara Ridge in the
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485:Seamounts of the Pacific Ocean
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139:; 54 years ago
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495:Natural disasters in Japan
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378:Global Volcanism Program
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383:Smithsonian Institution
500:1952 natural disasters
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46:11 metres (36 ft)
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204:Eruption of 1952-1953
465:Survey of Myojin-sho
89:31.9183°N 140.0217°E
420:1954GSAB...65..941D
242:Survey of 1998-1999
198:Shizuoka Prefecture
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490:Ephemeral islands
260:seabed topography
190:No.11 Myōjin-Maru
167:submarine volcano
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94:31.9183; 140.0217
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302:Bayonnaise Rocks
220:Kaiyo Maru No. 5
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43:Summit depth
480:Izu Islands
414:(10): 941.
373:"Myojinsho"
175:Izu Islands
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67:Coordinates
60:Izu Islands
474:Categories
446:2009-06-30
388:2018-01-05
359:References
313:Takane-shō
194:Yaizu City
154:Myōjin-shō
22:Myōjin-shō
436:0016-7606
296:Structure
282:Manbou II
278:Manbou II
266:Manbou II
252:Manbou II
179:eruptions
126:lava dome
80:140°1.3′E
77:31°55.1′N
51:Location
416:Bibcode
323:Gallery
223:of the
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115:Geology
105:Country
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256:Manbou
229:Manbou
183:island
306:somma
290:Shoyo
286:Shoyo
274:Shoyo
248:Shoyo
171:Tokyo
165:is a
109:Japan
56:Group
432:ISSN
250:and
144:1970
137:1970
121:Type
424:doi
192:of
160:明神礁
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