6:15 PM - 7:30 PM
[SVC45-P14] Volcanic activity of Nishinoshima volcano in 2013-2015
Nishinoshima volcano, which belongs to Ogasawara Islands (Bonin Islands), restarted its volcanic activity on November 20, 2013 and we already reported the status of its activity until April, 2014 at the meeting of the Japan Geoscience Union 2014. It has been active (as of January 21, 2015).
The Japan Coast Guard has been carrying out observation of Nishinoshima volcano in cooperation with the Tokyo Institute of Technology since the volcanic activity's restart was confirmed. We outline the observed development of volcanicity after the report at the previous meeting.
Lava was flowing out from several lava craters on the east side of the newly formed land and the lava enlarged the new land to the east direction from May to July 2014.
A lava mound was formed in the then largest crater on August 26, 2014.
A large quantity of lava was flowing out into the north direction of Nishinoshima on September 17, 2014. Then, the lava reclaimed the new land area from shallow waters on the north side of Nishinoshima and "Nishinoshima-Shinto" formed at the previous volcanic eruption of Nishinoshima from 1973 through 1974 was buried. The original island of Nishinoshima was almost buried by December 25, 2014 and a small-scale lava field has been formed.
On the other hand, a large pyroclastic cone has been being formed near the centre of the newly formed land. A few craters on the pyroclastic cone repeated Strombolian eruption from April to July 2014. Now, there is only one active crater after the lava mound formation in August 2014 and the pyroclastic cone has been growing stably and steadily.
The Japan Coast Guard has been carrying out observation of Nishinoshima volcano in cooperation with the Tokyo Institute of Technology since the volcanic activity's restart was confirmed. We outline the observed development of volcanicity after the report at the previous meeting.
Lava was flowing out from several lava craters on the east side of the newly formed land and the lava enlarged the new land to the east direction from May to July 2014.
A lava mound was formed in the then largest crater on August 26, 2014.
A large quantity of lava was flowing out into the north direction of Nishinoshima on September 17, 2014. Then, the lava reclaimed the new land area from shallow waters on the north side of Nishinoshima and "Nishinoshima-Shinto" formed at the previous volcanic eruption of Nishinoshima from 1973 through 1974 was buried. The original island of Nishinoshima was almost buried by December 25, 2014 and a small-scale lava field has been formed.
On the other hand, a large pyroclastic cone has been being formed near the centre of the newly formed land. A few craters on the pyroclastic cone repeated Strombolian eruption from April to July 2014. Now, there is only one active crater after the lava mound formation in August 2014 and the pyroclastic cone has been growing stably and steadily.