20/08/2015. English. Copahue, Sakurajima, Nevado Del Ruiz.
Copahue, Chili :
This seismic swarm was located 11.9 km north-northeast (NNE) of the main crater with a depth of 4.41 km. No changes were recorded in the activity on the volcano area , which are attributable to the swarm. In addition, there were no reports of noticeable earthquakes around the volcano, said the agency.
Since then, the swarm has decreased and the number of events is returned to the level recorded before. The OVDAS maintains its level of technical level yellow alert and Onemi maintains the yellow alert for the municipality of Alto Bio Bio, as of June 3, 2013, when the level of red alert was taken away. It also remains a high risk area, the first 2.5 kilometers around the crater and it is recommended to limit the approach to this sector.
Sakurajima, Japon :
The volcano is still in level 4 and access to 3km from the top is firm. No restriction to access at the « volcano peninsula« , the authorities allowed the free movement but only short stops are tolerated on observation points and parking are closed!
Some Japanese TV crews are present too!
The planes that serve the Kagoshima airport continues to pass very close to the volcano and a very low altitude!
Yesterday, bubbles of volcanic gases, near the Sakurajima were observed in the sea, at Sakurajima Port–Futamata.
Nevado del Ruiz, Colombie :
Yellow activity level or (III): changes in the behavior of volcanic activity.
Regarding the monitoring of the activity of the Nevado del Ruiz volcano, the SERVICIO Geologico COLOMBIANO through the OBSERVATORIO VULCANOLÓGICO Y SISMOLÓGICO OF MANIZALES, reports that:
During the last week, the seismicity related to fluid dynamics process in the volcanic system remains predominant; which shows the instability of the volcano for some time, as evidenced by the different volcanic monitoring parameters. This activity is mainly located in the Arenas crater, east, south and southeast of it, and was characterized by the recording of multiple episodes of volcanic tremors, which are associated with the movement of fluids , gases and ash emissions into the atmosphere.
In addition, has continued the recording of seismic activity associated with the fracturing of the rock in the volcanic structure. Earthquakes are located mainly in the northwest of the volcano and, in lesser amounts, in the Northeast, Southwest; at depths between 2.2 and 6.7 kilometers. The maximum magnitude recorded during the week was 1.4 ML (local magnitude), corresponding to an earthquake located 1.7 km north-east of Arenas crater, which was held on August 15 at 4:06 p.m. (local time) at a depth of 3.77 km. Continuous volcanic deformation show some changes.
The volcano continues to emit into the atmosphere of significant amounts of water vapor and gases, including sulfur dioxide (SO2). The gas and steam column reached a height of 1,000 meters above the summit of the volcano, and is sometimes seen with gray tones due to the presence of volcanic ash. The direction of the dispersion of the column was in harmony with the wind regime, which remained mainly to the western sector of the volcanic structure.
Source : SGC ( http://www2.sgc.gov.co/ )