Volcanos

Roundup of Global Volcanic Activity

Etna (Sicily, Italy): INGV Catania published the result of very high-resolution satellite-based measurements of ground deformation of Etna during the period between Feb 2015-Feb 2016. They show that Etna's dominant trend of deformation has changed from inflation (in blue) to deflation since the latest eruption in early December. Inflation of the entire volcanic edifice continued until November 2015, before the violent paroxysmal episodes occurred in December. During this event, the deflation that accompanied the eruptive activity has almost completely neutralized the preceding inflation, which likely means that most of the accumulated magma inside the volcano had been erupted during the recent activity.

Sakurajima (Kyushu, Japan): The activity at the volcano has decreased again over the past 2 weeks. The average size and frequency of explosions has dropped to one every few days (compared to several / day earlier in February). So far, March has only seen 3 explosions recorded by JMA. Something new, however, is that a number of the recent explosions came not from the Showa crater, but from the Minamidake summit crater, the older one of the two, located west above the former one. Minamidake had been Sakurajima's main active vent for decades since 1955, until a new crater on its eastern flank began to form and gradually "take over" in 2006 and became known as the Showa crater. In the past few years, only very few explosions were recorded from Minamidake,- nearly all activity had been at Showa crater, but this might have changed very recently.

Soputan (North Sulawesi, Indonesia): A small group of VolcanoDiscovery just returned from a visit to Soputan. While clouds prevented detailed observations most of the time, glow was visible from the summit at night and moderate steaming during the day. No other unusual events were observed (rockfalls, movements of the recent lava flows etc). This suggests that effusive activity if at all is very weak at the lava dome occupying the summit crater.

Momotombo (Nicaragua): Explosions seem to have ceased during the past week. Glow remains visible at the crater, suggesting that lava continues to be present there.

Nyiragongo (DRCongo): A cook who spent the night of 10 March on the rim of the crater reported that the volcano was unusually "noisy”. While we have no other specific information, it suggests that the very high level of activity, both from the main lava lake and at the new vent NE of it, first observed on 1 March, continues.