The March 16 volcanic-ash eruptions were accompanied by long-duration surface earthquakes and avalanches. Ash clouds stretched for 75 km east of the volcano.
Seismic stations continue to register sporadic volcanic tremors in the active-dome area.
The Shiveluch volcano, which towers 3,283 meters above sea level, remained dormant for quite a while, roaring back to life January 11, 2004.
The volcano doesn't threaten nearby populated localities so far; however, its activity can cause mud flows. Such mud flows have repeatedly eroded a local road in the past.
Ash clouds and emissions threaten aircraft because volcanic-ash particles can damage aircraft engines; moreover, unexpected eruptions make navigation more difficult.
The largest and most disastrous Shiveluch eruptions take place every 100-300 years. The most recent eruptions were registered in 1854 and 1964, respectively. Meanwhile weak and medium-force eruptions happen much more often.