Actualité volcanique, Articles de fond sur étude de volcan, tectonique, récits et photos de voyage
Par Bernard Duyck
The island of Nishino -shima , located in Izu- Bonin- Marianas arc continues to evolve since the eruption of 1973-1974 , during which it has grown .
It is the top of a large submarine volcano ; the south, west and northeast flanks are covered with prominent peaks satellites .
1973-74 eruptions have emerge and reach new lands.
Bathymetry of the submarine volcano and emergent Nishino -shima land - doc . http://www1.kaiho.mlit.go.jp
In November 2013 , after the appearance of a discolored water area, a surtseyan eruption occurs southeast of Nishino -shima . The new island has grown since , and effected a junction with the former , exceeding this in size .
Nishino -shima - the "old" island and the emerging new volcano 11/21/2013 - photo Japan Coast Guard .
Nishino -shima on 02/16/2014 - junction took place - course of the lava flows in every direction, and position three vents ( red) - doc.aist
An aerial inspection by the Geological Survey of Japan, on 28 February 2014, shows emissions of ash and steam at the two cones of the last eruption ( see video). Castings in all directions reach the sea to the east, south-southeast and west-northwest . Closure by coalescence of the lava flows left a small lake, with a temporary existence , which eventually disappear through evaporation.
Nishino -shima 02/28/2014 - two cones are smoking / Degasing - Track the entry of lava flows into the ocean are visible on both sides - photo Japan Coast Guards
Nishino -shima 02/28/2014 - Closure by coalescence castings left a small lake, temporary existence , which eventually disappear through evaporation. - photo Japan Coast Guards .
Vidéo AIST 02.03.2014
Sources:
- Japan Coast Guards - link
- Geological Survey of Japan - link
- Global Volcanism Program - Nishinoshima
Thème Magazine - Hébergé par Overblog