An ash cloud forming at Pico do Fogo volcano on Cape Verde Islands in December 2014.Marc Szeglat/AP Updates on some eruptions across the globe this week: Cape Verde Islands: Earthquakes on Brava in the Cape Verde Islands noticed on August 1 have prompted a heightened alert and evacuations of over 300 people from the slopes of the volcano. Brava has no known eruptions in the past 10,000 years, although many of the cones and flows on the volcano look relatively young. Based on its location in an oceanic island chain (like Hawai'i), you might expect lava flows from Brava. However, some of what are thought to be the most recent eruptions are phonolite, which is a stickier lava with higher silica content that can produce explosive eruptions. Combine that with interaction with groundwater on Brava, and we could see an explosive eruption. Only two years ago, Fogo in the Cape Verde Islands had one of its most specular eruptions in decades, with lava flows that overran multiple villages. Indonesia:Rinjani on the Indonesian island of Lombok had an unexpected explosive eruption on August 1. The eruption came from the Barujari crater inside the Rinjani caldera, the source of most of the activity at the volcano over the last few hundred years. Interestingly,
BNPB spokesperson Sutopo suggested that a nearby M5.7 earthquake was the trigger of the eruption at Rinjani. The eruption itself produced a plume that may have reached as high as 10 kilometers (32,000 feet; see below).
