By ExploreNow Editor, on May 7th, 2012%
Volcano Type: Stratovolcano
Volcano Status: Historical
Last Known Eruption: 2002
Summit Elevation: 394 m 1,293 feet
Latitude: 30.480°N 30°28’48″N
Longitude: 140.306°E 140°18’22″E
The circular, 2.7-km-wide island of Tori-shima in the southern Izu Islands is capped by an unvegetated summit cone formed during an eruption in 1939. Fresh lava flows from this eruption form part of the northern coastline of the basaltic-to-dacitic edifice. The volcano is also referred to as Izu-Tori-shima to distinguish it from the several other Japanese island volcanoes called Tori-shima (“Bird Island”). The main cone is truncated by a 1.5-km-wide caldera that contains two central cones, of which 394-m-high Iwo-yama is the highest. Historical eruptions have also occurred from flank vents near the north coast and offshore submarine vents. A 6-8 km wide submarine caldera lies immediately to the north of Tori-shima.
Click Here For The Rest Of Tori-shima, Izu Islands, Japan
Originally posted 2010-08-19 04:17:43.
By ExploreNow Editor, on April 29th, 2012%
Volcano Type: Complex volcano
Volcano Status: Historical
Last Known Eruption: 1996
Summit Elevation: 1500 m 4,921 feet
Latitude: 32.757°N 32°45’24″N
Longitude: 130.294°E 130°17’40″E
The massive Unzen volcanic complex comprises much of the Shimabara Peninsula east of the city of Nagasaki. A 30-40-km-long, E-W-trending graben extends across the peninsula. Three large stratovolcanoes with complex structures, Kinugasa on the north, Fugen-dake at the east-center, and Kusenbu on the south, form topographic highs on the broad peninsula. Fugen-dake and Mayu-yama volcanoes in the east-central portion of the andesitic-to-dacitic Unzen volcanic complex have been active during the Holocene. The Mayu-yama lava dome complex, located along the eastern coast west of Shimabara City, formed about 4000 years ago and was the source of a devastating 1792 AD debris avalanche and tsunami. Historical eruptive activity has been restricted to the summit and flanks of Fugen-dake. The latest activity during 1990-95 formed a lava dome at the summit, accompanied by pyroclastic flows that caused fatalities and damaged populated areas near Shimabara City.
 Fugen Click Here For The Rest Of Unzen, Kyushu, Japan
Originally posted 2010-08-30 04:18:55.
By ExploreNow Editor, on April 25th, 2012%
Volcano Type: Submarine volcano
Volcano Status: Historical
Last Known Eruption: 1916
Summit Elevation: 136 m 446 feet
Latitude: 31.436°N 31°26’9″N
Longitude: 140.054°E 140°3’13″E
Smith Rock is a steep-sided basaltic pinnacle that forms part of the outer southern flank of a 8-9 km wide submarine caldera that truncates a 20-km-wide seamount. The caldera was formed between about 60,000 and 30,000 years ago. The Shirane dacitic central cone, 3 km wide and 800 m high, rises to within 8 m of the sea surface in the eastern side of the caldera, whose 600-700 m high walls and outer flanks expose basaltic, andesitic, and rhyolitic rocks. Two large submarine cones, Sumisu Knolls No. 1 and 2, lie west of the caldera. Submarine eruptions have been reported from a number of locations near 136-m-high Smith Rock (also known as Sumisu-jima, or Smith Island), the last of which occurred in 1916. Water discoloration has been frequently observed since the 1970s near Smith Rock. In October 1992, a 6-km-long zone of discolored water was seen extending from the shallow Shirane rock mass near the eastern rim of the caldera, which rises to within 7 m of the sea surface and is the youngest feature of the volcanic complex.
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Originally posted 2010-08-16 08:26:20.
By ExploreNow Editor, on April 11th, 2012%
Volcano Type: Caldera
Volcano Status: Historical
Last Known Eruption: 2008
Summit Elevation: 1499 m 4,918 feet
Latitude: 43.384°N 43°23’3″N
Longitude: 144.013°E 144°0’46″E
Akan is a 13 x 24 km caldera located immediately SW of Kutcharo caldera. The elongated, irregular outline of the Akan caldera rim reflects its incremental formation during major explosive eruptions from the early to mid-Pleistocene. Growth of four post-caldera stratovolcanoes, three at the SW end of the caldera and the other at the NE side, has restricted the size of the caldera lake. Conical O-Akan volcano was frequently active during the Holocene. The 1-km-wide Nakamachineshiri crater of Me-Akan volcano was formed during a major pumice-and-scoria eruption about 13,500 years ago. Of the Holocene volcanoes of the Akan volcanic complex, only the Me-Akan group, east of Lake Akan, has been historically active, producing mild phreatic eruptions since the beginning of the 19th century. Me-Akan is composed of 9 overlapping cones. The main cone of Me-Akan proper has a triple crater at its summit. Historical eruptions at Me-Akan have consisted of minor phreatic explosions, but four major magmatic eruptions including pyroclastic flows have occurred during the Holocene.
Click Here For The Rest Of Akan, Hokkaido, Japan
Originally posted 2010-08-25 03:50:56.
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