OVSICORI-UNA reported that activity at Turrialba remained low during 8-9 June, characterized by minor degassing, along with small, sporadic long-period and low-frequency earthquakes. On 10 June at 0830 an explosion generated an ash plume that rose 500 m above the crater. Ash emissions and a few explosions continued until the afternoon; tremor levels decreased at 1415 and ash emissions ceased at 1457. Ashfall and/or a sulfur odor was reported in multiple areas of Valle Central including San Luis, Santo Domingo, Moravia, San Francisco, and Coronado. Tremor remained low during 11-13 June, and gas emissions rose no higher than 500 m above the crater during 11-12 June (cloud cover prevented webcam views on 13 June).

Geological Summary. Turrialba, the easternmost of Costa Rica's Holocene volcanoes, is a large vegetated basaltic-to-dacitic stratovolcano located across a broad saddle NE of Irazú volcano overlooking the city of Cartago. The massive edifice covers an area of 500 km2. Three well-defined craters occur at the upper SW end of a broad 800 x 2200 m summit depression that is breached to the NE. Most activity originated from the summit vent complex, but two pyroclastic cones are located on the SW flank. Five major explosive eruptions have occurred during the past 3500 years. A series of explosive eruptions during the 19th century were sometimes accompanied by pyroclastic flows. Fumarolic activity continues at the central and SW summit craters.

Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA)