Monthly Archives: February 2009

Barren Island, Andaman Islands, India

Based on analysis of satellite imagery, the Darwin VAAC reported that during 20-21 February ash plumes from Barren Island rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted about 75-90 km WNW, NW, and N. Source: Darwin … Continue reading

Posted in Volcano Activity Reports | Tagged

Redoubt, Alaska, USA

AVO reported that during 18-24 February seismic activity at Redoubt was variable but remained elevated above background levels. Web camera views and satellite imagery showed no unusual activity; steam plumes within the summit crater were seen on the web camera … Continue reading

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Galeras, Colombia

INGEOMINAS reported an explosive eruption from Galeras that began at 0705 on 20 February; the Alert Level was raised from II (Orange; “probable eruption in term of days or weeks”) to I (Red; “imminent eruption or in progress”), on a … Continue reading

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Chaitén, Chile

SERNAGEOMIN reported that on 19 February a partial lava-dome collapse of the S flank of Chaitén’s Domo Nuevo 1 and Domo Nuevo 2 lava-dome complex generated lateral explosions, block-and-ash flows, and pyroclastic flows. A pyroclastic flow traveled S down the … Continue reading

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How far can lava flow?

 A lot depends on the viscosity of the lava, the terrain on which it is emplaced, and the rate at which it is being erupted to the surface. Channel feeding aa lava flow, 1984 eruption of Mauna Loa. Photograph courtesy of … Continue reading

Posted in FAQ

What are the different types of lava flows and how do they form?

There are three types of basalt lava flows: pillow, pahoehoe, and aa. Pillow Lava: Pillow lavas are volumetrically the most abundant type because they are erupted at mid-ocean ridges and because they make up the submarine portion of seamounts and large intraplate volcanoes, like the … Continue reading

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How long does it take lava to cool?

Lava cools very quickly at first and forms a thin crust that insulates the interior of the lava flow. As a result, basaltic lava flows can form crusts that are thick enough to walk on in 10-15 minutes but the … Continue reading

Posted in FAQ