Kirishima volcano (Kyushu, Japan), activity update: growing lava dome, evacuation plans
Tuesday Feb 01, 2011 09:36 AM |
The lava dome inside Kirishima's crater is growing at a fast rate. Judging from areal photos, it now more than 500 m wide and well under way of soon over-spilling the Shinmoe-dake crater. If this happens, pyroclastic flows will likely be generated and could threaten nearby areas; although explosive activity has calmed down a lot, large explosions could occur any time. For this reason Japanese authorities have extended the exclusion zone from 2 to 3 km, and evacuated more than 600 residents of the town of Takaharu located on the eastern slope of Kirishima volcano.
The new lava dome inside Kirishima's Shinmoe-dake crater seen on 31 Jan 2011 and an infrared image showing the hot central part of the dome (Source:Japan Meteorological Agency - http://www.seisvol.kishou.go.jp/tokyo/volcano.html)
Scientists have observed ground deformation at Kirishima since Dec 2009. They estimate that ca 6 million m3 (0.006 km3) of magma have accumulated in a reservoir (magma chamber) at 6 km depth ca. 10 km WNW from Shinmoe-dake and 1 million m3 (0.001 km3) of magma at 3 km depth under the Shinmoe-dake cone itself.
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Sunday, Jan 30, 2011
The eruption at Kirishima seems to enter a more magmatic phase; while the ash plume further decreased and ash production declined, a new lava dome has appeared in the summit crater. Visible glow from the crater is now strong. [more]
Saturday, Jan 29, 2011
The eruption at Kirishima still goes on, but the plume height today is only half in height (reaching 3-4 km, according to VAAC Tokyo). Judging from photos of the webcamera and various reports, the intensity of the ash emission seems to have gone down compared to the past days. [more]
Friday, Jan 28, 2011
The eruption at Kirishima continues with strong ash emissions. Strong ash falls occurs in southern Kyushu. An ash plume from the eruption seems to reach 7.5 km (25,000 ft) elevation and is drifting southeast, causing (so far minor) disruptions to air traffic. ... [more]
Thursday, Jan 27, 2011
The explosive eruption of Kirishima goes on unabated. A dense column of ash is being emitted from the vent. Tokyo VAAC issued an ash cloud warning at flight level 210 - in other words, the eruption plume is estimated to have reached or could reach 21,000 ft (ca. 7 km.) ... [more]
A spectacular eruption started at Kirishima volcano on 26 January 2011. Violent explosions emit dense ash plumes and weak incandescent lava fountains. Small pyroclastic flows are devastating the lower slopes of the volcano, and many ballistic blocks impact in the vicinity of the crater. ... [more]