By ExploreNow Editor, on May 13th, 2012%
Volcano Type: Volcanic field
Volcano Status: Radiocarbon
Last Known Eruption: 2980 BC ± 150 years
Summit Elevation: 2400 m 7,874 feet
Latitude: 48.17°N 48°10’0″N
Longitude: 99.70°E 99°42’0″E
The Taryatu-Chulutu volcanic field lies in north-central Mongolia about 250 km west of Ulaanbaatar. This area, also known as the Hangayn or Tariat volcanic field, is located in a broad region of Miocene-to-Holocene basaltic lavas in the Baikal Rift System SSW of Lake Baikal.
Lava flows of four Miocene-to-Holocene age groups form terraces along the Chulutu (Chuloot) River; Pleistocene basalts form the 40- to 60-m terrace of the Taryatu basin. Six Holocene cinder cones, including Khorog (Horog) and Dzan Tologai, are concentrated along the Sumein and Gichgeniyn river valleys at the western end of the volcanic field.
The 180-m-wide crater of Khorog is breached to the south, in the direction of an associated lava flow. The Holocene cones produced thin, freshly preserved lava flows remarkable for their large numbers of ultramafic xenoliths. The lava flow from Khorog was radiocarbon dated at about 4930 years ago and dammed the Chulutu River, forming Lake Terkhin-Tsagan-Nur.
Originally posted 2010-10-04 15:10:26.
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.
Click Here For The Rest Of Smith Rock, Izu Islands, Japan
Originally posted 2010-08-16 08:26:20.
|
|
|
