when did ulawun last erupt

A police spokesman said ash was thought to be falling more than 30 km from the volcano. Seismic amplitudes were 30-40 times normal on 7 and 8 September, and the seismicity was characterized by irregular tremor produced by the frequent explosions. Amplitude measurements and RSAM monitoring were made difficult at the start of the month by storm-generated noise. Based on analyses of satellite imagery, the Darwin VAAC reported that during 14-15 February ash plumes from Ulawun drifted 45-95 km at altitudes of 2.4-3.7 km (8,000-12,000 ft) a.s.l. On 22 and 25 May, some plumes were partially gray. The decline in seismicity on 23 March was followed by almost 2 weeks of exceptionally low levels interrupted only by a brief increase, 30-31 March. Volcano seismicity remained at a low level with 10-30 small discrete B-type events/day.". An eruption occurred at Ulawun during 25-30 April 2001 (BGVN 26:06). No ash was reported after 21 December 2013. Sulfur-dioxide plumes drifted SE on 5 and 31 January. On 1 May, an ash plume rose to an altitude of 4 km and drifted W. [On 29 May 2007, RVO reported thick white vapor; there were no audible noises or night glow.] Both earthquakes occurred on the S side of West New Britain Province near Gasmata. A strong correlation between activity and preceding heavy rainfall (as observed in March) was not evident. The low-frequency earthquakes were slightly larger than the usual earthquakes recorded when Ulawun is quiet, but no particular pattern indicated that these earthquakes were forerunners to an eruption. On 22 June noises heard in villages to the NE accompanied some of the earthquakes. Volcano-tectonic earthquakes were recorded on 1, 3, 7, 8, 17, and 24 February, with daily totals ranging between 1 and 5. A Post Courier news article stated that the eruption began at 0230 on 29 September, but due to communication problems with the Rabaul Volcano Observatory's Mount Ulamona monitoring station they did not receive reports of the eruption until about 0800. By 30 September seismic activity was at moderate levels. On 1 October 2019 the seismicity increased, reaching RSAM values up to 10,000 units between 0130 and 0200, according to RVO. It is part of an island arc, a curved line of volcanoes that form above a subduction zone. Dike intrusions were also observed during the 1978 eruption at Ulawun, and resulted in surface fissure activity on the higher SE slopes and farther down on the E slope, which produced a lava flow. "After several weeks of intensified seismicity and occasional small phreatic explosions, a mild Strombolian eruption began on 4 September and ended on 11 September. MODVOLC Thermal Alerts, 2001-2002. RVO reported that increased seismic activity at Ulawun consisting of high-frequency volcano-tectonic (VT) earthquakes began on 7 June 2008. The seismograph, restored on 31 October 2003; showed seismicity was low throughout this period, with small low frequency volcanic earthquakes and some high frequency volcano-tectonic events. Records kept since Iceland was settled show that Eyjafjallajökull volcano erupted in 920, 1612 or 1613, and 1821–23. Visual observation reports during 1-21 December indicated that summit activity consisted of weak-to-moderate volumes of white vapor emissions. | May The RSAM values led to discussions with civil authorities and directions to local residents throughout the night at two-hour intervals. During the few hours before the start of the visible eruption on 7 May, patchy, weak tremor was recorded. Diffuse plume to altitude of 4.6 km drifted NW. Incandescence visible on the N flank was from either a lava flow or pyroclastic flow deposits. On 13 and 17 October small mudflows occurred, originating on the upper NW flanks and sweeping down a dry creek through Ubili village and then to the sea. Increasing seismicity then tephra ejection & lava flow. There was also a report of weak glow seen that night. Information Contacts: Rabaul Volcano Observatory (RVO), Geohazards Management Division, Department of Mineral Policy and Geohazards Management (DMPGM), PO Box 3386, Kokopo, East New Britain Province, Papua New Guinea; Darwin Volcanic Ash Advisory Centre (VAAC), Bureau of Meteorology, Northern Territory Regional Office, PO Box 40050, Casuarina, NT 0811, Australia (URL: http://www.bom.gov.au/info/vaac/); MIROVA (Middle InfraRed Observation of Volcanic Activity), a collaborative project between the Universities of Turin and Florence (Italy) supported by the Centre for Volcanic Risk of the Italian Civil Protection Department (URL: http://www.mirovaweb.it/); Global Sulfur Dioxide Monitoring Page, Atmospheric Chemistry and Dynamics Laboratory, NASA Goddard Space Flight Center (NASA/GSFC), 8800 Greenbelt Road, Goddard, Maryland, USA (URL: https://SO2.gsfc.nasa.gov/); Christopher Lagisa, West New Britain Province, Papua New Guinea (URL: https://www.facebook.com/christopher.lagisa, images posted at https://www.facebook.com/christopher.lagisa/posts/730662937360239 and https://www.facebook.com/christopher.lagisa/posts/730215604071639). 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