SERNAGEOMIN reported that on 5 November the S bank of the Chaitén River (locally known as the Blanco) had overflowed and flooded local houses due to intense rains a few days before.

Based on observations of satellite imagery and web camera views, the Buenos Aires VAAC reported that during 9-11 November ash plumes from Chaitén rose to altitudes 2.1-2.4 km (7,000-8,000 ft) a.s.l. and drifted ESE, E, and NE. A thermal anomaly was present on 10 November.

Geological Summary. Chaitén is a small caldera (~3 km in diameter) located 10 km NE of the town of Chaitén on the Gulf of Corcovado. Multiple explosive eruptions throughout the Holocene have been identified. A rhyolitic obsidian lava dome occupies much of the caldera floor. Obsidian cobbles from this dome found in the Blanco River are the source of artifacts from archaeological sites along the Pacific coast as far as 400 km from the volcano to the N and S. The caldera is breached on the SW side by a river that drains to the bay of Chaitén. The first recorded eruption, beginning in 2008, produced major rhyolitic explosive activity and building a new dome and tephra cone on the older rhyolite dome.

Sources: Servicio Nacional de Geología y Minería (SERNAGEOMIN), Buenos Aires Volcanic Ash Advisory Center (VAAC)