Volcanos

Roundup of Global Volcanic Activity - New Activity for the week of 15 February-21 February 2017

Barren Island | Andaman Islands (India) : The National Institute of Oceanography (NIO), part of the Council of Scientific and Industrial Research (CSIR), reported that a new eruption at Barren Island began on 23 January. Scientists aboard a research vessel were collecting sea floor samples when they observed a sudden ash emission. The team moved closer, about 1.6 km from the volcano, and noted small eruptive episodes lasting 5-10 minutes. Ash emissions were visible in the daytime, and lava fountains feeding lava flows on the flanks were visible at night. The team revisited the volcano on 26 January and observed similar activity during the four hours they stayed. They sampled sediments and water in the vicinity of the eruption and recovered volcanic ejecta.

Krakatau | Indonesia : PVMBG reported that seismicity at Anak Krakatau increased on 17 February, with earthquakes indicating emissions slowing transforming into continuous tremor. Harmonic tremor began to be recorded at 1810 on 19 February. Almost an hour later, at 1904, Strombolian explosions ejected incandescent material 200 m high.

Lanin | Central Chile-Argentina border : Servicio Nacional de Geología and Minería (SERNAGEOMIN) Observatorio Volcanológico de Los Andes del Sur (OVDAS) reported that beginning at 1524 on 15 February a seismic swarm at Lanin, consisting of 59 volcanic-tectonic, long-period, and spasmodic tremor events, lasted for 45 minutes. The largest volcano-tectonic event was a M 1.8. The Alert Level was raised to Yellow (second highest level on a four-colour scale); ONEMI declared an Alert Level Yellow (the middle level on a three-colour scale) for the community of Curarrehue (32 km N).

Pacaya | Guatemala : INSIVUMEH reported that during 14-21 February small Strombolian explosions at Pacaya’s Mackenney cone periodically generated small lava flows (200 m long on 21 February) that were active for hours at a time. CONRED noted that at night on 15 February residents in Los Positos in Villa Canales (13 km NE), and in Mesillas Altas and Bajas in Amatitlán (12 km N) reported vibrations and rumbling.

Piton de la Fournaise | Reunion Island (France) : OVPF reported that volcanic tremor at Piton de la Fournaise fluctuated during 14-21 February. Lava was mainly transported through a lava tube, and a few branches at end of tube were active.