Roundup of Global Volcanic Activity – New Activity for the week of 5 December – 11 December 2018
Manam | Papua New Guinea : The Darwin VAAC reported that on 6 December ash plumes from Manam were identified in satellite images rising to an altitude of 5.2 km (17,000 ft) a.s.l. and drifting SE. RVO noted that at 1215 on 8 December seismicity increased and indicated an eruption had begun, according to a news article. The eruption was characterized by forceful ash emissions, explosions that ejected lava fragments above the crater, and rumbling and roaring noises. Around 1300, based on pilot observations, information from RVO, and satellite images, large ash plumes rose as high as 15.2 km (50,000 ft) a.s.l and drifted E. Island reports noted that ejections of material ceased around 1900; audible noises ended around 1930. Satellite data indicated that ash from the high-altitude plume had begun to dissipate by 2020, and that on-going ash emissions rose to 8.2 km (27,000 ft) a.s.l. Island residents described heavy ashfall and that the sun was blocked by airborne ash, based on second-hand social media posts. News reports indicated that residents in Bokure and Kolang (NE and ENE flanks, respectively) had evacuated. Seismicity had declined by the end of the day. Dark ash plumes continued to be visible the next day, rising as high as 7.6 km (25,000 ft) a.s.l. and drifting E, though were less frequent.
Mayon | Luzon (Philippines) : PHIVOLCS reported that during 5-11 December white steam plumes periodically emitted from Mayon drifted mainly WSW. Crater incandescence was sometimes visible at night. A four-minute long event recorded by the seismic network began at 1224 on 9 December, and produced a grayish-brown ash plume that drifted W. The Alert Level remained at 2 (on a 0-5 scale) and PHIVOLCS reminded residents to stay away from the 6-km-radius Permanent Danger Zone and the 7-km Extended Danger Zone on the SSW and ENE flanks.