Kirishima (新燃岳 in Japanese), one of Japan's most active volcanoes. It is actually a group of 18 young, small stratovolcanoes north of Kagoshima Bay: Takachihonomine, Nakadake, Ohatayama, Karakunidake, Tairoike, Ohachi, and Shinmoedake are the principal vents.
Historic eruptions have been recorded since 742 and there are more than 60 recorded eruptions, mainly from Ohachi and Shinmoedake, with the exception of a small lava flow from Iwoyama in 1768. Relatively large eruptions occurred in 788, 1235, 1716-17 and 1768, and in 2011.
A violent eruption started at Kirishima on January 26, 2011, the largest one for more than 50 years.
No eruptions were observed at Shinmoedake since 7 September 2011 (last explosion on 1 March). Overall, the volcano's activity (seismicity, deformation, degassing) has been decreasing, JMA's November volcano activity summary reports: ...more
"Since September 2012, the volcanic seismicity has remained at slightly higher levels than that observed between June and August 2012, and a total of 40 earthquakes occurred in November. 4 hypocenters were determined to be located at the northeast of Shinmoedake, and most of other hypocenters were supposed to be just beneath the crater of Shinmoedake. No volcanic tremors were observed (as in October). According to regional deformation observations conducted by GSI, baseline extension caused by magma supply to a deeper chamber to the northwest of the crater gradually has slowed down to a static state since December 2011. [less]
As our colleague Marc Szlegat reported on Vulkane.Net, the alert level of the Japanese Kirishima volcano (Kirishimayama) was raised last month"orange". This is the third out of 4 warning levels and means that an eruption could occur any time. ...more
Last year in March, the Shinmoedake crater of the complex volcano Kirishima had a violent eruption that make the headlines. The volcano is located close to the other volcano currently on orange alert in Kyushu, Sakura-jima, which last week had a stronger explosion that caused ashfall in the nearby city of Kagoshima. [less]
Kirishima volcano near Kagoshima town on Kyushu Island exploded violently earlier today (13 March), sending an ash plume to 4 km elevation. This is the first significant activity since March 1. It can not be ruled out, but probably remains speculation that the violent 8.9 magnitude earthquake on 11 March played a role in the reawakening of Kirishima.
Over the past days, Kirishima's overall intensity of the eruption seems decreasing. Kirishima continues to grow its lava dome and produce small to moderate vulcanian-type explosions at rates of 5-10 per day. Strong pressure waves were accompanying the explosions and could be felt in Kirishima town. People are alerted not to approach the volcano in a radius of 4 km because of the risk of falling bombs. ...more
Ash from the various explosions (summarized in JMA's reports (Japanese Meteorological Agency, in Japanese) reaches 500-3000 m altitude and affects the SE of Kyushu island, where it causes much nuisance to life and infrastructure on ground as well disruption to air traffic. [less]
Another powerful vulcanian explosion from the new lava dome occured today at 15:54 pm. Ash reached an elevation of 15,000 ft (ca. 5 km) and an aviation warning was issued by VAAC Tokyo. ...more
Kirishima volcano had a strong explosion from the lava dome on 31 January. Windows were shattered by the pressure wave up to 8 km away, and bombs landed up to 2 km distance. Authorities have extended the exclusion zone to 4 km from the crater as new explosions can occur any time. ...more
According to the National Institute of Advanced Industrial Science and Technology this eruption of Kirishima is already 9 times larger than the 1959 eruption of the volcano, with over 70 million tonnes of ash and tephra erupted. [less]
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)
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. ...more
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. [less]
The new lava dome inside Kirishima's crater on 29 Jan (ANN news)
Webcam image on the evening of 30 Jan 2011 showing strong glow, possibly from a lava flow.
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.
Ash plume from Kirishima volcano drifting SE over Kyushu Island (26 Jan). Image credit: NASA Earth Observatory
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.
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
According to the Japanese Meteorological Agency monitoring the volcano, the eruption poses no thread to the population and a 2 km exclusion zone is established around the volcano. [less]
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
Some residents of Miyazaki city had been evacuated according to news, kindly forwarded by a reader of the excellent eruptions blog. A great time lapse video compiled from the webcam (http://www.seisvol.kishou.go.jp/vo/32.php, select ??? ????????= Kirishima volcano) was posted at: www.youtube.com/watch [less]
The eruption of Kirishima volcano (Photo: FNN news)
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
The ash plume is about 1.5 km high according to Japanese news, and the Tokyo VAAC issued an ash warning for Kirishima to elevations up to ~7.6 km / 25,000 feet. It appears the latest eruption comes from Shinmoe-dake vent of Kirishima volcano, whose last eruption started in 2008. [less]
