mercredi, avril 03, 2013
An eruption from Ivan Grozny volcano was reported yesterday by the Voice of Russia (German edition). According to the short news article, nearby villages received ash fall, and 2 millimeters of ash fell in Kurilsk town. Clouds prevented direct observations, and there was no sulfur odor detected. ... [details]
samedi, mars 30, 2013
Tokyo VAAC reported a possible eruption occurred yesterday around 11:00 GMT. A volcanic ash plume was observed at 7,000 ft (2.1 km) altitude and drifting eastwards. [details]
Grozny volcanGrozny volcano (Etorofu Yake-yama in Japanese) in central Iturup Island, Kuriles is one of the most frequently active volcanoes of the volcanic island chain.
It is a complex of 2 volcanoes: Ivan Grozny volcano and Tebenkov (also known as Odamoi-san) volcano.
Ivan Grozny volcano has a 3-3.5 km diameter caldera open to the south and includes the andesitic Grozny lava dome, whose name is also used for the whole complex. All known historic eruptions took place from Ivan Grozny volcano.
Introduction:To the NE, there are several other lava domes which are less than 10,000 years old. Their formation modified the shore of a former lake at the northern side of the caldera to extremely sinuous shape.
The forested andesitic Tebenkov volcano is located immediately NE of the Grozny dome complex. Machekh is a crater immediately south of Tebenkov and has strong fumarolic activity.
Source: GVP Grozny volcano information
A magnitude 5.1 earthquake occurred 12 km SE of Grozny volcano on 26 July 2009.
Small phreatic eruptions occurred from the Grozny lava dome between 3 May and August 1989. New fumaroles, fissures and small explosion craters as well as lahars were formed in the eruption. ...plus
A single weak (phreatic) explosion happened at Grozny volcano in January 1973.
Baransky volcanBaransky volcano (Sashiusu-dake in Japanese) is a stratovolcano in the center of Iturup Island, southern Kuriles. Only one historical eruption occurred in 1951 and consisted of weak explosions in the summit crater.
Strong fumarolic activity is in the summit and several flank craters. A geothermal field is found on the SW flank and contains hot springs and geysers. During a geothermal exploration in 1992 in this field, a small hydrothermal explosion took place inside an exploratory well and the exploration was abandoned.
Introduction:The Baransky stratovolcano was built on top of an older eroded volcano. It has a young summit lava dome cut by a NW-trending chain of small explosion craters. A group of flank cones farther to the NW with a similar NW-SE orientation is partially surrounded by lava flows from the central crater of the andesitic-dacitic volcano. Lava flows from Baransky descended 4-5 km SE to reach the Pacific Ocean along a broad front.
Source: GVP / Smithsonian Baransky volcano information
1992 hydrothermal explosion near drill well
An exploration well into a zone of hot water 4.5 km SW of the summit of Baransky Volcano (in the Kipyaschaya River valley) was drilled in the summer of 1991. Drilling was temporarily halted at Baransky in early August, but no casing was installed. Two weeks later, a hydrothermal explosion occurred 50 m upslope, forming a crater >10 m in diameter.
A mixture of vapor, water, and a large quantity of rock fragments was erupted for several days, destroying vegetation within 50 m. The explosion was believed to have occurred when hot water moved up the borehole after drilling ceased, and escaped through its uncased walls into a permeable fissured zone near the surface.
Source: GVP / Smithsonian monthly reports
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