Volcanos

Roundup of Global Volcanic Activity

Chirinkotan (Northern Kuriles): Ash emissions from small explosions at the volcano were detected on satellite imagery last Monday (20 July). The ash plumes rose to estimated 12,000 ft (4 km) altitude and drifted SE.

Sinabung (Sumatra, Indonesia): The volcano continues to slowly effuse viscous lava which feeds the lava dome on its summit. This activity results in numerous avalanches and pyroclastic flows. Several thousands of people continue to live in temporary shelters.

Nevado del Ruiz (Colombia): Intermittent ash emissions began to occur at the volcano again since 13 July. The volcano observatory of Manizales reports increased seismic activity, related to internal fluid movements and rock fracturing processes. Ash fall occurred on 13 July in nearby villages in up to 30 km distance to the southwest (in Chinchina). On 19 July, another series of explosions produced ash plumes that rose approx. 1 km above the crater and quickly dissipated.

Cotopaxi (Ecuador): Volcanic unrest continues. Yesterday, the Geophysical Institute registered 105 episodes of volcanic tremor and 3 volcano-tectonic earthquakes. SO2 emissions remain elevated, at nearly 3000 tons per day.

Sabancaya (Peru): Light ash emissions were reported this morning, rising to 20,000 ft (6 km) altitude. Seismic activity at the volcano remains low but above background. A slight increase in quakes related to internal fluid movements (gasses, water, magma) was noted during the past week. Staff from the INGEMMET volcano observatory visited the summit area on 9 and 10 July and sampled ash that had been erupted during the recent weeks. A significant fraction of the ash was confirmed to originate from fresh ("juvenile") magma (as opposed to older weathered rock fragments), which confirms that the volcano has entered a magmatic eruptive phase.