This was characterized by glowing lava fragments ejected by frequent explosions followed by small pyroclastic flows. There is no Deformation History data available for Ulawun. During mid-March 2002 through at least early February 2003, activity from the main crater and the N valley vents of Ulawun were unchanged and generally remained low. There were less forceful emissions of blue vapour, and no increase in the level of tremor associated with the increase in visual activity.
Pilot report noted an ash plume to an altitude of 2.4 km drifting SW. High-frequency volcano-tectonic earthquake, Felt by island residents with Modified Mercalli (MM) intensity up to IV, In central New Britain centered~30-40 km SSE of Bialla town (70-80 km). Volcano-tectonic earthquakes were recorded on 1, 3, 7, 8, 17, and 24 February, with daily totals ranging between 1 and 5. No change was noted in the summit crater emissions. Police were considering the evacuation of Ulamona Catholic mission, the settlement closest to the volcano. On 17 May, emissions became briefly forceful and booming noises were reported. Seismicity was at background levels. Continuous night glow and sub-continuous deep roaring sounds were reported from Nuau village and Ulamona Mission, both ~12 km from the summit, on the night of the 19th. Information Contacts: Ima Itikarai, Kila Mulina, and Steve Saunders, RVO. According to the Darwin VAAC, an ash-and-steam plume from Ulawun that was reported on 15 August by the US Air Force Weather Agency rose to an altitude of ~3.7 km (~12,000 ft.) a.s.l. A thin steam-and-ash plume reached an altitude of below 3 km. Seismicity continued at moderate level dominated by low frequency volcanic earthquakes. The main crater produced weak-to-moderate volumes of white and white-gray vapor. and drifted 65 km WSW and W. RVO reported that activity at Ulawun was low during 16-31 December; diffuse ash plumes rose from the crater during 51-21 December, and white vapor emissions were visible during 22-31 December. 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. "After several weeks of intensified seismicity and occasional small phreatic explosions, a mild Strombolian eruption began on 4 September and ended on 11 September. Very light ashfall was reported from Sule and Nuau. Incandescent nose of lava flow now lowdown in area devastated by nuee in northwest valley. During 5-8 July RVO noted a slight increase in seismicity (above moderate levels), which included tremor. Most ejecta were contained by the crater walls, but occasional larger explosions showered the upper flanks of the volcano with incandescent tephra. During late May through late June, RVO reported that white to gray plumes rose up to 1 km high and at times ashfall occurred. Seismicity remained generally low with ~20 small B-type events recorded daily. People on the S and SE sides of the island heard "low jetting" noises during 24-25 May 2010. Lahars were detected mid-month. RVO stated that RSAM values peaked at about 2,500 units during 1330-1600, and then dropped to 1,600 units as the eruption subsided. By 1100 silent ash clouds were seen forcefully rising ~200 m above the summit. Activity in November was relatively low, with only a variable amount of white gas-and-steam emissions visible and low (less than 200 RSAM units) seismicity with sporadic volcanic earthquakes. A slight increase in seismicity occurred in December after waning temporarily at the beginning of October (BGVN 16:10). Behavior in the days prior to the 25 April eruption. On 24 April at 1400 the tremors increased again, making it hard to detect patterns in the analog records. Information Contacts: Ima Itikarai, Rabaul Volcano Observatory (RVO), P.O. The average flux was 120 t/d, an increase from 1983 values (97, 70, 49, 66 t/d) that yielded an average of 70 t/d. 1973. and drifted over 30 km SE, SW, and W. RVO reported that during 16-31 October activity at Ulawun was at low levels. Information Contacts: H. Patia, P. de Saint-Ours, and B. Talai, RVO. Sabretoothed69, 2010 (uploaded on 7 November 2010), YouTube (URL: http://www.youtube.com/watch?v=UnCSeky3Mes, uploaded by sabretoothed69). The eruption plume was about 10 km long and trended approximately S. During the day the rate of ash production increased, resulting in a dense pall of ash on the E side of the volcano. ", Large gas plume and numerous weak earthquakes. Catalog number links will open a window with more information. Ulawun Location:on the island of New Britain, Papua New Guinea Elevation: 2,334 m Type of volcano: stratovolcano Activity: one of the most active volcanoes in Papua New Guinea. "Z," spoken as Zulu, is shorthand for Coordinated Universal Time (UTC). Table 5. On 30 April around noon, a few hours after reports of an eruption at Ulawun, the Earth Probe TOMS detected a SO2 cloud over SW New Britain,. At certain places the flows spread laterally. RVO reported that during 1-6 and 10-26 May white plumes rose above Ulawun's summit crater, and during 7-9 and 27-31 May gray-brown ash plumes rose from the crater. Card 0856 (27 January 1970)A. Renwick, Geological and Volcanological Branch, Administration of Papua and New Guinea, Port Moresby, Territory of Papua/New Guinea. | November
Audible explosions at intervals and slight increase in amplitude of continuance tremor.". On 14 May, an ash plume from Ulawun of unknown height was visible on satellite imagery. On 14 June the Rabaul Volcanological Observatory (RVO) recommended that the Alert Level be reduced from 2 to 1. Mount Ulawun volcano erupts with hot ash and lava sent flying into the sky; ... 62, looks the same as she did 30 years ago when she was in Last Of The Mohicans as … Unfortunately, no base line measurements are available to check whether deformation had occurred prior to the eruption.". The Darwin VAAC reported that on 28 August at 0732 a low-level ash cloud from an eruption at Ulawun was visible on satellite imagery. Limited evacuations occurred on 3 May due to the occurrence of relatively high seismic activity and the possibility of further volcanic activity. Earlier, occasional forceful emissions of weak to moderate gray ash clouds had begun at about 0600 on the 25th, and occasional low rumbling noises began at about 1600. At 0400 on the 7th the lava ejections were more frequent, occurring at intervals of 1 minute or less. All of the events in this period were of very small magnitude. It is possible that the earthquake opened microfissures in the volcanic edifice allowing ground water to penetrate and interact phreatically with shallow magma. Assistance was later provided by the West New Britain Provincial Government. RVO reported that during 13-14 and 17 May gray-to-brown ash plumes rose above Ulawun. The last major eruption was in 1992. Ongoing sporadic tremors followed the 28 September 2000 eruption for most of October-January. The Darwin VAAC reported that a possible low-level ash plume was visible on satellite imagery on 14 April. By 4 August RSAM values reached 600, attributed to an increase in volcanic tremor. Preliminary information was based on news media reports and aviation sources. "At the commencement of the strong, visible activity, the seismic activity intensified dramatically, becoming continuous tremor, which persisted until about 1215 on 7 October. Diffuse plume to altitude of 4.6 km drifted NW. RVO noted that seismicity was at a low to moderate level, dominated by small low-frequency volcanic earthquakes. The seismic station 2.9 km W of the volcano was restored on 4 July and recorded small sub-continuous tremors. Those 2001 alerts corresponded with new vents and large plumes in early 2001 (BGVN 26:05, 26:06). continued through June. Information Contacts: I. Itikarai and P. de Saint-Ours, RVO. A small cone was being constructed in the summit crater, but some ejecta were falling outside the crater rim. ", "The volcano was very quiet throughout December with only continuous moderate emission of white vapour from the summit crater. The only break in activity was in February, March, and the first part of April. During 15-28 April the seismicity level was low, however from 29 April seismicity increased to a moderate level following an episode of continuous volcanic tremor. The next day weak-to-moderate thin white vapor was observed. The period 25 June-22 July was quiet, with no audible noise or night-time glow, and weak to moderate volumes of vapor from the main summit crater. Red incandescence was seen at the base of the column. The Rabaul Volcano Observatory (RVO) has since provided more accurate and detailed reports for the August-October 2000 period. It was not possible to confirm these observations from the conventional seismograph due to severe radio interference. Locals heard roaring and rumbling during 0600-0800. The entire period of tremor lasted about 6 hours. However, activity is still above normal levels. RVO recommended that the Alert Level be reduced to Stage 2. The Rabaul Volcano Observatory (RVO) confirmed the report. Numerous volcanic earthquakes continued over the next 2 days and a stage-1 alert warning of an increased risk of an eruption was issued on 5 November. The 2002 Eruption – Nyiragongo last eruption The 2002 Eruption – Nyiragongo last eruption. Information Contacts: Ima Itikarai, Rabaul Volcano Observatory (RVO), P.O. On 30 September small volcanic earthquakes began around 1000 and continued to increase in frequency; by 1220, they were characterized as a seismic swarm. No damage or casualties were reported. Included in the tremor were discrete B-type events. | April
Activity during 2010. A Geological Survey report (at 01/0001Z) noted the summit activity was relatively quiet for last 24 hours. Most advanced less than 4 km from the crater, but a few traveled about 5 km downslope. Information Contacts: D. Lolok, R. Stewart, and B. Talai, RVO. Usually, 300-500 small events were recorded/day. "The eruption, characterized by generally low-intensity Strombolian activity, terminated on 27 January. The various images acquired by astronauts and satellites are stunning. There were no reports of anomalous activity until 29 September 2000 when a moderate-sized eruption occurred. | August
All observers reported that these avalanches originated directly from the crater, and were not formed by collapse of the eruption column. Ulawun remained quiet throughout September and October 2009. "One or more nuées ardentes traveled down the SE flank at the peak of this phase, starting at about 1545, but were not directly observed, being on the opposite side of the volcano to the observation post. . "A notable seismic crisis occurred 21-23 March. Small, felt earthquakes occurred and the sound of roaring was heard by nearby villagers. NASA satellite images provided by the Air Force Weather Agency showed a NW-trending plume on 6 September (figure 7). On 9 August a plume drifting to the S was visible on satellite imagery (figure 10). "Unrest appeared related to the amount of rainfall on the volcano. At the peak of seismicity (about 20 times normal levels, on 8 January), weak ejections of incandescent tephra occurred at a rate of 1-2/minute from one or two vents in a mound of fresh lava in the summit crater. There were some variations in the tremor level 26-27 January, producing slight 'banding' on Helicorder records. The Darwin VAAC issued a volcanic ash advisory stating that volcanic activity was reported to them at 0605 through an air report from Air New Guinea airline, but there was evidence of an ash cloud in satellite imagery starting at about 0400. and that the eruption ceased by ~1530 on 30 April. Its base begins over 1000 meters below the surface of the Tyrrhenian Sea and it rises to a… The RSAM values reflect an increase in seismicity dominated by volcanic tremor. ", "Activity remained at a low level in October. Four traverses yielded SO2 emission rates of 149, 66, 120, and 134 t/d. After almost three years without reports, ash plumes again rose from the crater during October and November 2016. The volcano last erupted on July 3, when a 35-year-old Italian hiker was killed by falling debris. The initial 22 August report noted "thin plume to FL 100 [~ 3 km altitude] extends 60 NM [~ 110 km] to SW on NOAA 15 [image of 2038 UTC on 22 August] . 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. Aerial inspection 2-4 May showed no significant change in summit morphology. Records showed periods of low background seismicity interspersed with sub-continuous low-frequency (B-type) events of small to large amplitude, or periods of non-harmonic tremor lasting 1/2-2 hours. Reports from Diego Coppola and David A. Rothery provided analyses of MODIS thermal alerts during 2001 and 2002 (using the MODVOLC alert-detection algorithm) extracted from the MODIS Thermal Alerts website (http://modis.hgip.hawaii.edu/) maintained by the University of Hawaii HIGP MODIS Thermal Alerts team (BGVN 28:01). Low-level activity; moderate white-blue summit emissions, "Activity continued at a low level in February. This issue supplements the Bulletin reports with those from the Darwin VAAC archives (table 2), which included information provided from ground, airborne, and space-based sensing. According to another news source an observer in a helicopter reported a column of incandescent material rising from the crater, residents noted that the sky had turned black, and a main road in the N part of the island was blocked by volcanic material. Information Contacts: I. Itikarai, P. de Saint-Ours, and C. McKee, RVO. One high-frequency earthquake and small periodic volcanic tremors were recorded. The last few years have seen almost constant activity at Ulawun, with frequent small explosions, and have caused great damage and loss of life. Provisionally, the flow may contain 20 x 106 m3 of lava. stratovolcano. Catalog of Active Volcanoes of the World and Solfatara Fields, Rome: IAVCEI, 5: 1-105. RVO reported in similar terms for the period 15 March-1 April, noting also that tiltmeter measurements recorded a long-term inflationary trend. RSAM values slightly increased at 0600 on 28 June and fluctuated between 80 to 150 units afterwards. Also beginning in August, an electronic tiltmeter located on the flanks ~2.5 km WSW of the crater vent began to show some inflation on the NS component. Residents also reported a lava flow near Noau village and Eana Valley. The emissions varied in strength, and during an aerial inspection it was possible to see into the crater, which is elongated in an E-W direction, with its largest dimension ~100 m. No base could be seen to the crater, and the emissions were being released from very deep on the E side. and drifted WSW. By 0600 dense light-gray ash emissions were drifting NW, causing ashfall in areas downwind including Ulamona Mission. Russia's Raikoke Volcano erupted last weekend for the first time in 95 years. According to the Darwin VAAC, a NOTAM (Notice to Airmen) stated that on 8 June an ash plume from Ulawun rose to an altitude of 2.1 km (7,000 ft) a.s.l. This compilation of synonyms and subsidiary features may not be comprehensive. When the system was restored, daily earthquake totals were ~400-500. A distinct lull also preceded the third period. "It is interesting to note that the high level of seismicity closely followed a heavy rainfall of 65 mm. In retrospect one might speculate that the seismic swarm and inflation were signs of rapid intrusion of significant volumes of magma to a shallow depth. RSAM values fluctuated but decreased overall. Prior measurements in 1983 and 1989 were 71 and 120 t/d, respectively. Stage 2 hazard status was recommended at 1630 on the 27th. According to a Post-Courier news article, ash eruptions had occurred on 26 August and during the previous week, but became larger on the 27th. The cloud was visible on satellite imagery at 0632 drifting WSW. Tremor ceased altogether with the end of explosive activity on 13 May. Information Contacts: Patrice de Saint-Ours, Steve Saunders, and Ben Talai, RVO. This pattern of seismicity had begun on 26 October 1988. Seismic activity and emissions remained at high levels until 8 November when they abruptly declined to normal again, allowing a return to a stage-1 alert. Periods of volcanic tremor were recorded on 15 and 29-31 May.". The summit crater emitted white and blue vapours in weak to moderate amounts. A small landslide scar appeared near the N valley flank vent, reportedly caused by movement of a large boulder and loose material, triggered by a M 6.1 earthquake that occurred near Pomio (55 km SSE) on 19 November. Variable amounts of emergent vapor and minor debris flows at Ulawun were reported during January-March 2003 (BGVN 28:03). "Previous Ulawun eruptions developed rapidly (within hours) to full-scale eruptions, including lava effusion and paroxysmal explosive activity culminating in the formation of pyroclastic flows. A report by an aircraft of volcanic activity [on 29 April] at about 2130Z with smoke/ash cloud up to 9 km, and confirmed by the RVO and satellites surveillance, initiated a series of Volcanic Advisories. Using infrared satellite Moderate Resolution Imaging Spectroradiometer (MODIS) data, scientists at the Hawai'i Institute of Geophysics and Planetology, University of Hawai'i, developed an automated system called MODVOLC to map thermal hot-spots in near real time. High-frequency volcanic earthquakes were recorded occasionally throughout October. At 1930 their frequency started to increase, and from 2000 they became subcontinuous (1800/day) and moderate in amplitude. After the mild eruption on 19 October, in November the activity at Ulawun reverted to its usual low level, gently releasing variable amounts of vapor. Galeras Volcano Geology and Hazards. . Trees in path of nuee burning. Visible shock waves were generated by the stronger explosions. The last eruption on Nea Kameni occurred in 1950. According to the Darwin VAAC, a pilot observed an ash plume from Ulawun on 21 September rising to an altitude of 3.7 km (12,000 ft) a.s.l. However, these emissions changed through the month to strong thick white vapour and there were occasional reports of grey and blue emissions. The Darwin VAAC issued several notices about ash plumes visible in satellite data. Seismicity was still strong at the end of the month. During 6-24 August, white and gray-to-brown plumes rose no more than 300 m above Ulawun, and fine ash fell on the NW and W flanks. . Conditions for observing Ulawun were poor in February. RVO reported that white vapor plumes rose 300 m above Ulawun during 21-29 July. and drifted S and SE. The eruption was described as a distinct incandescent glow formed from ejecting material rising less than 100 m above the vent. RVO reported that on most days during 16-30 November small volumes of gray to gray-brown ash plumes rose 100 m from the crater and drifted S. On 21 November ashfall was reported in Navo on the SW flank. Information Contacts: Rabaul Volcano Observatory, Papua New Guinea.
Box 386, Rabaul, Papua New Guinea. Ulawun Volcano, Papau New Guinea, one of the "Decade Volcanoes" There was some discussion earlier about the so-called "Decade Volcanoes", so I thought I'd … "At the end of the month, the summit crater was gently releasing a weak to moderate white vapour plume and seismicity was at a very low level. After 22 February tremor returned to background levels. The cause of this is not known. Observers in aircraft approaching from the NE noted that at about 0640 the emission cloud above Ulawun was slightly more voluminous than normal, and was reported as pale to dark. Ulawun remained quiet through mid-September 2005, with the summit crater releasing weak to moderate volumes of thick white vapor. On 1 and 2 June only white vapor emissions were noted. The first of these moderate-sized avalanches was observed moving down the N flank at about 0715 on the 19th. Seismicity was at a low level between 16 and 27 May, after which time none was recorded. Lava flow ceased altogether, probably during the night of 14-15 May, just as the flow front had finished blocking the main channel of the Pandi River (about 11 km from the volcano), diverting it into an existing older channel. However, in mid-August the amplitudes of volcanic earthquakes increased markedly, and by late August the frequency of occurrence of volcanic earthquakes was increasing. Weak and fluctuating incandescence was seen from the S at night during 28-29 May. The eruption lacked lava flows. Larger events began to occur in mid-September. Located in the province of Batangas, the volcano is the second-most active volcano in the Philippines, with 34 recorded historical eruptions, all of which were concentrated on Volcano Island, near the middle of Taal Lake. Loose ash was stirred up by the flow and produced an 'eruption-like' plume. Information Contacts: Ima Itikarai, Rabaul Volcanological Observatory, P.O. The build-up to the second phase was very rapid. 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To high winds or other signs of activity was normal, with occasional white/blue in...