On 29 May the Fukushima Local Meteorological Observatory reported that seismic activity increased slightly beneath Azuma during May. The Coordinating Committee for the Prediction of Volcanic Eruptions' seismic network detected 51 small-magnitude volcanic earthquakes during 21 and 22 May and 39 on 21 May (the most recorded in one day since November 1998). During March four low-frequency tremor events were recorded, while 40 were detected in April.

30 May 2001            Back to Top

On 29 May the Fukushima Local Meteorological Observatory reported that seismic activity increased slightly beneath Azuma during May. The Coordinating Committee for the Prediction of Volcanic Eruptions' seismic network detected 51 small-magnitude volcanic earthquakes during 21 and 22 May and 39 on 21 May (the most recorded in one day since November 1998). During March four low-frequency tremor events were recorded, while 40 were detected in April.

Sources: The Japan Times

Below is a summary of eruption dates and Volcanic Explosivity Indices (VEI).

The following references are the sources used for data regarding this volcano. References are linked directly to our volcano data file. Discussion of another volcano or eruption (sometimes far from the one that is the subject of the manuscript) may produce a citation that is not at all apparent from the title. Additional discussion of data sources can be found under Volcano Data Criteria.

Hasenaka T, Ui T, Nakamura Y, Hayashi S, 1992. Traverse of Quaternary volcanoes in Japan. {29th Internatl Geol Cong, Kyoto, Field Trip A06}, 74 p

IAVCEI, 1973-80. Post-Miocene Volcanoes of the World. {IAVCEI Data Sheets, Rome: Internatl Assoc Volc Chemistry Earth's Interior}.

Japan Meteorological Agency, 1996. {National Catalogue of the Active Volcanoes in Japan (second edition)}. Tokyo: Japan Meteorological Agency, 502 p (in Japanese)

Kudo T, Hoshizumi H, 2006-. Catalog of eruptive events within the last 10,000 years in Japan, database of Japanese active volcanoes. Geol Surv Japan, AIST, http://riodb02.ibase.aist.go.jp/db099/eruption/index.html

Kuno H, 1962. Japan, Taiwan and Marianas. {Catalog of Active Volcanoes of the World and Solfatara Fields}, Rome: IAVCEI, 11: 1-332

Nakano S, Yamamoto T, Iwaya T, Itoh J, Takada A, 2001-. {Quaternary Volcanoes of Japan}. Geol Surv Japan, AIST, http://www.aist.go.jp/RIODB/strata/VOL_JP/

Sumi K, Takashima I, 1976. Absolute ages of the hydrothermal alteration halos and associated volcanic rocks in some Japanese geothermal fields. {In}: {Proc 2nd United Nations Symp Devel Use Geotherm Resour, San Francisco}, 1: 625-634

The Azuma volcanic group consists of a cluster of stratovolcanoes, shield volcanoes, lava domes, and pyroclastic cones. The andesitic and basaltic complex was constructed in two E-W rows above a relatively high basement of Tertiary sedimentary rocks and granodiorites west of Fukushima city. Volcanic activity has migrated to the east, with the Higashi-Azuma volcano group being the youngest. The symmetrical Azuma-Kofuji crater and a nearby fumarolic area on the flank of Issaikyo volcano are popular tourist destinations. The Azuma complex contains several crater lakes, including Goshiki-numa and Oke-numa. Historical eruptions, mostly small phreatic explosions, have been restricted to Issaikyo volcano at the northern end of the Higashi-yama group.