Past activity of Mt. Asama Repeated eruption from the Meiji era to the 1950s August 7 22:22
Asama is an active volcano with an altitude of 2568 meters on the border between Gunma and Nagano.
Mt. Asama repeated eruptions every year from the Meiji era to the Showa 30s, and in the foot region, damage was caused by volcanic blocks and volcanic ash.
In recent years, an explosive eruption occurred in 2004, and cinders flew up to the mountainside. It was confirmed that a small cinder of up to 3 centimeters fell in a place about 6 km northeast.
After that, in February 2009, the volcanic plume rose to a height of 2000 meters from the crater, and a large volcanic block flew from the crater to about 1 km.
Volcanic ash was swept away by the wind, and ash fall was confirmed in Nagano and Gunma prefectures as well as Saitama and Tokyo, and Izu-Oshima.