Puyehue-Cordón Caulle volcano (Central Chile and Argentina): alert status raised to Yellow

The Argentine Mining Geological Service (SEGEMAR) reported that the alert status for the volcanic complex has been elevated to YELLOW on 26 April due to an increased ground deformation.
Based on data collected from GNSS stations near the volcanic complex and analysis of RADAR satellite images using InSAR technology, an active inflation zone has been identified since 2012. Its maximum deformation is approximately 6 km west-northeast of the emission center linked to the 2011 eruption. Vertical rise rates have increased during the initial months of this year, peaking at an average of 2.4 cm per month, the highest rates recorded since monitoring began. The accumulated vertical displacement at the GNSS station located 3 km from the maximum inflation zone now stands at 42 cm.
Moreover, since mid-2020, there has been a rise in high-magnitude volcano-tectonic (VT) and hybrid (HB) seismic activity (M≥3.0), primarily linked to a surface source near the 2011 eruption center. However, the seismic activity related to internal fluid movement within the volcano remains low.
Simultaneously, gas emissions and surface areas registering temperatures close to 90°C have been observed in the vicinity of the emission point of the 2011 eruption. These phenomena are likely associated with the presence of a shallow magmatic body left over from the previous eruption.
Source: Argentine Mining Geological Service volcano activity update 29 April 2024