Volcanos

Roundup of Global Volcanic Activity

Bulusan | Luzon (Philippines) | 12.77°N, 124.05°E | Elevation 1565

PHIVOLCS reported that, beginning at 1654 on 16 September, a four-minute-long phreatic explosion at Bulusan generated a dark gray ash plume that rose 1.5 km and drifted NE. Ashfall was reported in the municipalities of Casiguran, Gubat, and Barcelona. The Alert Level remained at 1, indicating abnormal conditions and a 4-km-radius Permanent Danger Zone (PDZ).

Klyuchevskoy | Central Kamchatka (Russia) | 56.056°N, 160.642°E | Elevation 4754 m

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 9-16 September. Volcanic bombs that were ejected above the summit crater and the cinder cone landed in the Apakhonchich drainage on the E flank. A lava flow traveled down the Apakhonchich drainage and also down the SW flank. Satellite images showed a large and bright daily thermal anomaly at the volcano. On 10, 13, and 15 September ash plumes rose as high as 7 km (23,000 ft) a.s.l. and drifted 50 km NE and SE. The Aviation Color Code remained at Orange.

Piton de la Fournaise | Reunion Island (France) | 21.244°S, 55.708°E | Elevation 2632 m

OVPF reported that volcanic tremor at Piton de la Fournaise stabilized during 14-17 September. Field observations on 15 September revealed that the two volcanic cones that had formed on the lower part of the fissures had begun to coalesce. Lava from the northernmost cone flowed N and NE, and by 0900, was active midway between Piton Partage and Nez Coupé de Sainte Rose. The height of the lava fountains grew in the afternoon, rising as high as 60 m, likely from activity ceasing at the southernmost cone and focusing at one main cone. On 16 September the main cone continued to build around a 50-m-high lava fountain; lava flows from this vent traveled NE. Tremor rose during the night on 17 September, and then fell sharply at 0418 on 18 September, indicating the end of surficial activity. During 11-18 September the erupted volume was an estimated 7 million m3.

Turrialba | Costa Rica | 10.025°N, 83.767°W | Elevation 3340 m

OVSICORI-UNA reported that starting at 0210 on 13 September ash emissions from Turrialba rose 300 m and drifted NNW. A small explosion was detected later that day at 1947. Small explosions were detected at 1804 and 2147 on 15 September. On 16 September small explosions were recorded at 0240, followed by three periods of passive ash emissions. An explosion at 1100 on 16 September generated an ash plume that rose 50 m above the crater and likely drifted S (inclement weather prevented visual observations). Ashfall was reported in the Parque Nacional Braulio Carrillo, and areas E of San José and Heredia including Ipís de Guadalupe.

A series of gas-and-ash emissions began at 0958 on 17 September with an ash plume that rose 400 m above the crater and drifted NW. Plumes the rest of the day did not exceed that height, though an explosion at 2148 generated a plume that rose 500 m. Ash-and-gas emissions were recorded on 18 September; some plumes were observed rising as high as 500 m, although inclement weather hindered most observations. Explosions during four energetic periods on 19 September generated ash plumes that rose as high as 4 km. A sulfur odor and ashfall was reported in many communities in the Valle Central including those in San José (35 km WSW), Heredia (38 km W), Alajuela, and Cartago (25 km SW). According to news articles, flights in and out of the Juan Santamaría International Airport were canceled; the airport remained closed at least through the morning of 20 September. The Pavas San José Tobías Bolaños Airport was also temporarily closed. At night during 19-20 September ash emissions rose as high as 500 m and drifted WNW. Ash plumes during the rest of 20 September rose as high as 700 m. Plumes drifted NW and NE.

White Island | North Island (New Zealand) | 37.52°S, 177.18°E | Elevation 321 m

Based on field observations of White Island on 14 September, GeoNet reported that the eruption which had occurred the day before had ceased. An analysis of collected ash deposits revealed no juvenile components. Seismic and acoustic activity remained low, and gas flux had not changed since before the eruption. On 15 September the Volcanic Alert Level was lowered to 2 and the Aviation Colour Code was lowered to Yellow. Observations during 17-18 September suggested no new sustained ash emissions (web camera images indicated that very minor amounts of ash may have been present in the steam plumes); the Volcanic Alert Level was lowered to 1.