Erupting volcanoes - Nishinoshima, Villarica, Cascades Range

03/04/2015. - Nishinoshima, Japon : 

Nishinoshima Island volcano continues its activity, lava flows  increase its size with also volcanic ash emissions. A reconnaissance flight carried 25 March 2015 found that the eruptions are still common, between 5 and 6 per minute, while the activity is similar to that observed in the previous flight of February 23. However, since February 23, 2015, there has been little increase in the size of the island. This is because most of the flows have changed direction, and instead of going to the west, they now flow north on the oldest lava. They move slowly, perhaps because they slow down because of the topography. Moreover, contrary to February, the volume of volcanic ash emitted into the atmosphere has increased suggesting that the starting point of the eruptions is deeper.


  March 25, 2015. The "pen" gray rises to the south at about 1300 m. On the coast, the water is yellow and green colors. Nishinoshima, Japan. Japan Coast Guard. JCG

The professor
Nogami , of Tokyo Institute of Technology said that a more explosive eruption could occur.

size:
East-West: 2000 meters. (February 23: 1950 m) .Nord South: 1 800 meters, unchanged.  
The new area is 2.45 km2, an increase of 0.16 km2 since 25 December 2014. The total size of the island is 2.46 km2, including part of the land that is still not covered by the lava.
http://www1.kaiho.mlit.go.jp/GIJUTSUKOKUSAI/kaiikiDB/2013nishinoshima/photo150325/photo002_20150325_105859.jpg 
First approach to the island by boat from the start of the eruption:
A navy ship made an approach to the island for the first time since November 2013. The scientists, mainly from the Japan Agency for Marine Science and Technology, said they were watching small earthquakes and tsunamis associated with microseismic activity of the seabed and landslides from the volcanic soil near the island. They could be installed six measuring equipment on the seabed near the island to monitor earthquakes and tsunamis.

http://www1.kaiho.mlit.go.jp/GIJUTSUKOKUSAI/kaiikiDB/2013nishinoshima/photo150325/photo004_20150325_105911.jpg

The form of the shock wave was recorded from the data associated with a video made from the boats and a bathymetric survey was conducted at 6 km, not observing any activity or changes from 2008. The team also plans to establish a system to monitor conditions in real time on the island.

Source : AVCAN. Photos : Garde cote japonaise. 

Villarica, Chili :
The system shows volcanic activity similar to that reported in recent days, recording seismic signals continued, with a slight upward trend and temporal correspondence with acoustic signals associated with the appearance of small Strombolian explosions in the behavior of the crater.

Such behavior is part of the suggested alert type for the moment. The volcanic system is in a phase of increased volatility, which may progress rapidly to an eruptive pulse similar to that occurred on 3 March, with possibly of lava emission. The alert level remains at ORANGE, according to the protocol which means "probable eruption in the short term."
Source : Sernageomin . Photo : Puconia.cl.

Cascades Range Volcanoes, United States of America :

Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN

Activity Update: 
All volcanoes in the Cascade Range of Oregon and Washington are at normal background levels of seismicity. These include Mount Baker, Glacier Peak, Mount Rainier, Mount St. Helens, and Mount Adams in Washington State; and Mount Hood, Mount Jefferson, Three Sisters, Newberry, and Crater Lake in Oregon. Additionally, GPS data from most of the major volcanoes, and sparse real-time hydrologic and geochemical monitoring, show no anomalous activity.

 
Recent Observations:
Mount Rainier experienced a short-lived earthquake swarm March 23/24, with most events occurring during a ~30-minute burst on March 23. The Pacific Northwest Seismic Network located twenty of these events, centered mainly beneath the upper south flank at 2/3 km depth. Magnitude of the located events ranged from 1.6 down to negative 0.7. Such swarms occur sporadically at Mount Rainier, but this week  was the most substantial, by number of earthquakes, since a ~1000-event episode September 20/22, 2009. An analysis published in 2013 suggests that earthquakes of the 2009 swarm were initiated by hydrothermal fluid movement along cracks or small faults, as is likely the case for the March 23/24 swarm.


 Source : CVO.
 Photo : Walter Siegmund
 
http://volcansvanuatueruptionsgb.blogspot.fr/2015/04/03042015-nishinoshima-villarica-chaine.html

Comments