Chile’s National Geology and Mining Service has issued an orange alert for Nevados de Chillán, a complex of snow-capped stratovolcanoes located in the Ñuble region near the country’s border with Argentina.
The agency’s level-orange alert signifies a significant uptick in volcanic activity.
According to NASA’s Earth Observatory: “Like other historically active volcanoes in the central Andes, the Nevados de Chillán were created by upwelling magma generated by eastward subduction, as the dense oceanic crust of the Pacific basin dove beneath the less dense continental crust of South America. The rising magmas associated with this type of tectonic environment frequently erupt explosively, forming widespread ash and ignimbrite layers. They can also produce less explosive eruptions, with voluminous lava flows that layer together with explosively erupted deposits to build the classic cone-shaped edifice of a stratovolcano.”
According to Chile’s geology and mining agency: “The main volcanic hazards associated with the CVNCh correspond to lahars, debris flows and lava flows, channeled through the main valleys: Estero Renegado, Estero Shangri-La, Chillán River, Estero San José, Santa Gertrudis River, Gato River and Las Minas River . The generation of lahars configures the greatest potential danger for the population surrounding the volcano, given its proximity to the channels and the amount of snow and ice on the summits of the complex. Ash fall determined by the dominant wind direction.”
Read more on GlacierHub: