Authorities have raised the alert for a volcano in eastern Indonesia and told hundreds of residents to evacuate following increased activity.
Mount Egon in East Nusa Tenggara province had rumbled since Tuesday morning as its magma pressure increased, said Sutopo Nugroho, spokesman for the National Disaster Management Agency on Wednesday.
About 600 residents living in a village near the peak have been advised to evacuate, as the exclusion zone has been extended from 1.5 kilometres to 3 kilometres, he said.
The alert was raised to the second-highest level.
The 1703-metre volcano last erupted in 2008, forcing more than 10,000 people to flee.
Visually, no visible change in the color and height of the smoke emitted by the volcano Egon, not always seen because of the fog. However, a thin white smoke was still visible rising from 25 meters, generated by the energy under the mountains of Egon, which tends to fluctuate.
Seismicity is still dominated by volcanic earthquake (VA), harmonic tremors, and emission earthquakes. After a rise in the level of activity on December 15, 2015, the number of seismic events of Egon tended to decrease. But these days , it shows a considerable increase in RSAM activity after the earthquake felt at 9:36:08 p.m..
Generally, the type of eruption of Mount Egon is phreatic. This type of eruption may occur if the interaction between the magma comes into contact with water under the surface (hydrothermal) which leads to changes in the liquid phase from vapor, producing changes in volume (pressure), which can destabilize the cap of rocks near the surface of the crater. The symptoms currently observed are identical to the symptoms of increased seismic activity before the eruption of Mount Egon on April 15, 2008, which lasted a relatively short time. Although it can be established when the eruption of Mount Egon will occur, anticipatory efforts and disaster mitigation efforts need to be improved.
Based on the analysis of seismic observation data, the nature / type of eruption of Gunun Egon, and potential dangers , from January 13, 2016 at 18:00 The level of activity of Egon is raised from level II (Waspada) to level III (Siaga).
If there is a decrease / increase in volcanic activity of Egon significantly, the activity level can be lowered / raised in accordance with the level of threat.
January 13 , 2016 . Egon, Indonesie :
Source : Tempo. co , Vsi .
Photos : Projet Gaia , Didier Larive .