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Lewotolok

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  • Indonesia
  • Indonesia
  • Stratovolcano
  • 2021 CE
  • Country
  • Volcanic Region
  • Primary Volcano Type
  • Last Known Eruption
  • 8.274°S
  • 123.508°E

  • 1431 m
    4695 ft

  • 264230
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number
Most Recent Weekly Report: 21 July-27 July 2021 Citation IconCite this Report

PVMBG reported that daily white-and-gray plumes from Lewotolok rose as high as 800 m and drifted in multiple directions during 20-25 July. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


Most Recent Bulletin Report: February 2021 (BGVN 46:02) Citation IconCite this Report

New eruption in late November 2020 consisting of ash plumes, crater incandescence, and ashfall

Lewotolok (also known as Lewotolo) is located on the eastern end of a peninsula connected to Lembata (formerly Lomblen) that extends north into the Flores Sea. Eruptions date back to 1660, characterized by explosive activity in the summit crater. Typical activity has consisted of seismicity and thermal anomalies near the summit crater (BGVN 36:12 and 41:09). A new eruption that began in late November 2020 was characterized by increased seismicity, dense, gray ash plumes, nighttime crater incandescence, and ashfall. This report covers activity through January 2021 using information primarily from the Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM, or the Center of Volcanology and Geological Hazard Mitigation), MAGMA Indonesia, and satellite data.

Summary of activity during February 2012-October 2020. Activity from February 2012 to November 2020 was relatively low and consisted primarily of a persistent thermal anomaly in the summit crater since at least March 2016 and occasional white gas-and-steam emissions. During January 2012 intermittent white gas-and-steam plumes rose 15-500 m above the crater, accompanied by crater incandescence; no thermal anomalies were reported during 16-24 January. On 6 January there were 500 people in the Lembata district evacuated due to reports of ash plumes that were observed by local residents, the smell of sulfur, and the sound of rumbling (BGVN 36:12).

Thermal activity dates back to 13 October 2014 using MODIS data in MODVOLC satellite data (BGVN 41:09; figure 3). According to the MODVOLC algorithm, a total of seven thermal alerts were detected on 13 October 2014 (1), 27 September 2015 (1), 2, 3, and 4 (2) October 2015, and 5 November 2017 (1). The number of thermal alerts in both MODVOLC and Sentinel-2 satellite data had increased slightly in 2020 compared to 2018 and 2019, though cloud cover often prevented visual confirmation for the latter (figure 3). Sentinel-2 thermal satellite imagery captured occasional thermal anomalies in the summit crater during 2016-2019 (figure 4). White gas-and-steam plumes were intermittently reported from September 2017 through 2 March 2018 that rose as high as 500 m above the crater and drifted dominantly E and W, according to PVMBG.

Figure (see Caption) Figure 3. Graph comparing the number of thermal anomalies using MODVOLC alerts and Sentinel-2 satellite data for Lewotolok during January 2014-January 2021 for MODVOLC and 20 March 2016-January 2021 for Sentinel-2 thermal satellite data. Data courtesy of HIGP - MODVOLC Thermal Alerts System and Sentinel Hub Playground.

Brief seismicity, which included shallow and deep volcanic earthquakes was detected during October 2017. On 9 October 2017 PVMBG issued a VONA (Volcano Observatory Notice for Aviation) reporting that white gas-and-steam emissions rose 500 m above the crater. On 10 October BNPB (Badan Nacional Penanggulangan Bencana) reported that five earthquakes 10-30 km below Lewotolok and ranging in magnitude of 3.9-4.9 as recorded by Badan Meteorologi, Klimatologi, dan Geofisika (BMKG). These seismic events were felt by local populations and resulted in an evacuation of 723 people. The only activity reported between January 2018 and October 2020 was white gas-and-steam plumes that rose 5-100 m above the crater drifting primarily E and W and an occasional thermal anomaly in the summit crater (figure 4).

Figure (see Caption) Figure 4. Sentinel-2 thermal satellite imagery shows a thermal anomaly in the summit crater of Lewotolok during 20 March 2016 (top left), 8 July 2017 (top right), 13 July 2018 (bottom left), and 12 August 2019 (bottom right). Sentinel-2 satellite images with “Atmospheric penetration” (bands 12, 11, 8A) rendering. Courtesy of Sentinel Hub Playground.

New eruption starting in November 2020. On 26 November 2020 a continuous tremor began at 1943, followed by a series of volcanic earthquakes at 1947 and deep volcanic earthquakes at 1951, 1952, 1953, and 2255; white gas-and-steam emissions rose 20 m above the crater. Deep volcanic earthquakes were again recorded at 0242, 0537, 0556 on 27 November. At 0557 an explosion produced a gray ash plume that rose 500 m above the crater and drifted W; by 0630 the plume turned white, according to PVMBG (figure 5). Seismicity decreased slightly after the explosion, but tremor continued. During 27-28 November dense white gas-and-steam plumes rose as high as 500 m above the crater and nighttime crater incandescence was observed.

Figure (see Caption) Figure 5. Webcam image of a dense gray ash plume rising 500 m above the crater of Lewotolok on 27 November 2020. Courtesy of MAGMA Indonesia.

During the morning of 29 November seismicity increased again and consisted of six deep volcanic earthquakes, continuous tremor occurred around 0930. A second explosion was recorded at 0945 that produced an ash plume 4 km above the crater, accompanied by incandescent material that was ejected above the crater (figure 6). The ash plume consisted of two levels: the lower-level drifted W and NW and the upper-level drifted E and SE. The large, gray ash plume was captured in a satellite image as it spread generally E and W (figure 7). Ashfall and a sulfur odor was reported in several surrounding villages; videos from social media showed tephra falling onto the roofs of residential areas. BPBD evacuated residents in 28 villages in two sub-districts; by 29 November at 1300 about 900 people had been evacuated. At 1900 Strombolian activity was observed and during the night, crater incandescence was visible.

Figure (see Caption) Figure 6. Photos of the eruption at Lewotolok on 29 November 2020 that produced a dense, gray ash plume 4 km above the crater. Courtesy of Devy Kamil Syahbana, PVMBG (left) and MAGMA Indonesia (right).
Figure (see Caption) Figure 7. Satellite image showing a strong gray ash plume above Lewotolok on 29 November 2020, expanding roughly E and W. Courtesy of Sentinel Hub Playground and the European Space Agency, Copernicus.

The eruption continued from 29 November into 1 December, where the white-and-gray ash plumes rose 700-2,000 m above the crater and drifted SE and W, accompanied by incandescent material that was ejected above the crater and the smell of sulfur, according to PVMBG (figure 8). A large sulfur dioxide plume was reported drifting SE and extending over the N half of Australia by 30 November (figure 9). By 1300 that day, 4,628 people had been evacuated. Incandescent lava flows near the summit were visible and incandescent material traveled down the flanks during 30 November and 1 December.

Figure (see Caption) Figure 8. Webcam image of the continuous eruption at Lewotolok showing a dense gray ash plume rising above the cloud-covered summit on 30 November 2020. Courtesy of MAGMA Indonesia.
Figure (see Caption) Figure 9. SO2 plume from Lewotolok captured by the Sentinel-5P/TROPOMI instrument on 30 November 2020 drifting SE and along the N part of Australia. Courtesy of Simon Carn and the NASA Global Sulfur Dioxide Monitoring Page.

White-and-gray plumes continued frequently through January 2021, rising 100-1,500 m above the crater, drifting in multiple directions, accompanied by nighttime crater incandescence and occasional incandescent ejecta (figure 10). During 1-8 December gray plumes rose 100-1,000 m above the crater and drifted E, W, and SW accompanied by nightly crater incandescence and incandescent material ejected as high as 20 m above the crater. By 5 December at 2200 about 9,028 residents had been evacuated to 11 evacuation centers, according to BNPB. Black, gray, and brown ash plumes were visible daily during 9-15 December, rising 1 km above the crater, accompanied by nightly Strombolian explosions that ejected material above the crater. More Strombolian explosions on most nights over 16-29 December ejected material 100-300 m above the crater; in addition, the sounds of rumbling and banging could be heard. The material was deposited as far as 1 km from the crater E and SE during 24-25 and 27-31 December and 4-7 January 2021. Strombolian activity continued into January, accompanied by frequent gray-and-white ash plumes, rumbling and banging sounds, and incandescent ejecta up to 600 above the crater that extended as far as 500 m E, SE, and W. Crater incandescence was visible up to 600 m above the crater.

Figure (see Caption) Figure 10. Webcam images showing continuing dense gray ash plumes from Lewotolok on 1 December 2020 (top) and 8 January 2021 (bottom). Courtesy of MAGMA Indonesia.

A consistent level of thermal activity was recorded in the Sentinel-2 MODIS Thermal Volcanic Activity from February 2019 through October 2020; in early December 2020 a slight increase in thermal anomalies were detected (figure 11). This data reflects the start of the new eruption in late November 2020. According to the MODVOLC thermal algorithm, five thermal hotspots were detected between January 2020 and January 2021 on 3 September (1), 29 November (2), 24 December (1), and 5 January 2021 (1). Some of this thermal activity was also observed in Sentinel-2 thermal satellite imagery in the summit crater (figure 12).

Figure (see Caption) Figure 11. Sentinel-2 MODIS Thermal Volcanic Activity data (bands 12, 11, 8A) shows consistent thermal activity (red dots) at Lewotolok during February 2020 through December 2020. Stronger thermal anomalies in early December is likely due to the new eruption that began in late November 2020. Courtesy of MIROVA.
Figure (see Caption) Figure 12. Sentinel-2 thermal satellite imagery showing a thermal anomaly in the summit crater of Lewotolok on 25 October (top left), 9 November (top right), and 3 January 2021 (bottom right). On 14 December (bottom left) a Natural Color image showed a gray ash emission above the clouds and drifted E. On 3 January 2021 (bottom right) two thermal anomalies were visible in the summit crater accompanied by gas-and-steam emissions drifting NE. Sentinel-2 satellite images with “Natural Color” rendering (bands 4, 3, 2) on 14 December 2020, all other images use “Atmospheric penetration” (bands 12, 11, 8A) rendering. Courtesy of Sentinel Hub Playground.

Information Contacts: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as Indonesian Center for Volcanology and Geological Hazard Mitigation, CVGHM), Jalan Diponegoro 57, Bandung 40122, Indonesia (URL: http://www.vsi.esdm.go.id/); Badan Nasional Penanggulangan Bencana (BNPB), National Disaster Management Agency, Graha BNPB - Jl. Scout Kav.38, East Jakarta 13120, Indonesia (URL: http://www.bnpb.go.id/); MAGMA Indonesia, Kementerian Energi dan Sumber Daya Mineral (URL: https://magma.vsi.esdm.go.id/); 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/); Hawai'i Institute of Geophysics and Planetology (HIGP) - MODVOLC Thermal Alerts System, School of Ocean and Earth Science and Technology (SOEST), Univ. of Hawai'i, 2525 Correa Road, Honolulu, HI 96822, USA (URL: http://modis.higp.hawaii.edu/); Sentinel Hub Playground (URL: https://www.sentinel-hub.com/explore/sentinel-playground); European Space Agency (ESA), Copernicus (URL: http://www.esa.int/Our_Activities/Observing_the_Earth/Copernicus); NASA 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/); Simon Carn, Dept of Geological and Mining Engineering and Sciences, Michigan Technological University, 1400 Townsend Dr., Houghton, MI 49931, USA (URL: https://so2.gsfc.nasa.gov/).

Weekly Reports - Index


2021: January | February | March | April | May | June | July
2020: November | December
2017: October
2012: January
2011: December
2004: July


21 July-27 July 2021 Citation IconCite this Report

PVMBG reported that daily white-and-gray plumes from Lewotolok rose as high as 800 m and drifted in multiple directions during 20-25 July. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


14 July-20 July 2021 Citation IconCite this Report

PVMBG reported that daily white-and-gray plumes from Lewotolok rose as high as 1 km and drifted W, NW, NE, and E during 13-20 July. Rumbling was heard daily. Incandescent material was ejected as far as 1 km from the summit vent in various directions during 16-18 July. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


7 July-13 July 2021 Citation IconCite this Report

PVMBG reported that daily white-and-gray plumes from Lewotolok rose as high as 1.1 km and drifted SW, W, and NW during 6-12 July. Incandescent material was ejected from the summit vent on 6, 8, and 10 July; on 6 July material landed as far as 300 m away. The Darwin VAAC noted that on 7 July an ash plume rose 2.7 km (9,000 ft) a.s.l. and drifted E, based on satellite data and information from PVMBG. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM); Darwin Volcanic Ash Advisory Centre (VAAC)


30 June-6 July 2021 Citation IconCite this Report

PVMBG reported that daily white-and-gray plumes from Lewotolok rose as high as 1 km and drifted in multiple directions during 29 June-6 July. Incandescent material was ejected from the summit vent in various directions during 2-5 July; on 3 July material landed as far as 1 km SW and started vegetation fires. On 5 July an ash plume rose 1 km and drifted SE. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


23 June-29 June 2021 Citation IconCite this Report

PVMBG reported that daily white-and-gray plumes from Lewotolok during 22-29 June rose as high as 600 m and drifted W. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


16 June-22 June 2021 Citation IconCite this Report

PVMBG reported that white-and-gray plumes from Lewotolok rose as high as 1 km and drifted W and NW daily during 16-22 June. Incandescent material was ejected as high as 500 m above the summit and 300-500 m away from the vent in multiple directions almost daily. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


9 June-15 June 2021 Citation IconCite this Report

PVMBG reported that white-and-gray plumes from Lewotolok rose as high as 800 m and drifted W and E almost daily during 9-15 June. Incandescent material was ejected 200-500 m SE during 8-10 June. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


2 June-8 June 2021 Citation IconCite this Report

PVMBG reported that white-and-gray plumes from Lewotolok rose as high as 500 m and drifted W and E almost daily during 1-8 June. Rumbling was heard every day. Crater incandescence was visible during 1 and 3-4 June. Incandescent material was ejected as far as 300 m in all directions during 3-4 June and as far as 1 km NW during 5-6 June. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


26 May-1 June 2021 Citation IconCite this Report

PVMBG reported that white-and-gray plumes from Lewotolok rose as high as 1 km and drifted W and E during 27-28 and 30-31 May. Rumbling was sometimes heard. Crater incandescence was visible on 31 May. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


19 May-25 May 2021 Citation IconCite this Report

PVMBG reported that white-and-gray plumes from Lewotolok rose as high as 800 m and drifted W and E during 18-24 May. Rumbling was heard almost daily. Crater incandescent was visible on 18 May and on 22 May incandescent material was ejected 400-700 m to the SE. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


12 May-18 May 2021 Citation IconCite this Report

PVMBG reported that white-and-gray plumes from Lewotolok rose as high as 600 m and drifted W and NW during 12-17 May. Incandescent material was ejected 100-300 m above the summit during 14-16 May and 300 m SE on 15 May. Rumbling and thumping sounds were heard during 14-17 May. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


5 May-11 May 2021 Citation IconCite this Report

PVMBG reported that mostly white plumes from Lewotolok rose as high as 600 m and drifted SE, W, and NW during 4-11 May. Gray-and-white plumes rose 500 m and drifted W, NW, and SE on 6 and 8 May. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


28 April-4 May 2021 Citation IconCite this Report

PVMBG reported that white plumes from Lewotolok rose as high as 500 m and drifted SE, SW, and W on most days during 27 April-3 May. Gray-and-white plumes rose 500 m and drifted W on 30 April and 2 May. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


21 April-27 April 2021 Citation IconCite this Report

PVMBG reported that the eruption at Lewotolok continued during 20-27 April. Black, gray, and white plumes rose as high as 1 km above the summit and drifted E, SE, and W on most days. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


14 April-20 April 2021 Citation IconCite this Report

PVMBG reported that the eruption at Lewotolok continued during 13-19 April. Gray-and-white ash plumes rose as high as 1.5 km above the summit and drifted E and W. Rumbling was often audible. Incandescent material was ejected 300-1,000 m above the summit during 14-16 April. Incandescent material was ejected to the E during 9 and 11-12 April. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 4 km away from the summit crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


7 April-13 April 2021 Citation IconCite this Report

PVMBG reported that the Strombolian eruption at Lewotolok continued during 6-13 April. Gray-and-white ash plumes rose as high as 750 m above the summit and drifted in multiple directions. Incandescent material was ejected 300-500 m above the summit on most days and 500 m SE on 8 April. Incandescent material was ejected to the E during 9 and 11-12 April. Rumbling was occasionally audible. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 4 km away from the summit crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


31 March-6 April 2021 Citation IconCite this Report

PVMBG reported that the Strombolian eruption at Lewotolok continued during 30 March-6 April. Gray-and-white ash plumes rose as high as 700 m above the summit and drifted in multiple directions, though rainy weather conditions prevented visual observations during 2-3 and 5 April. Incandescent material was ejected 300-500 m above the summit and 500 m SE during 30-31 March; eruptive events were recorded by the seismic network on the other days but not visually confirmed. Rumbling was occasionally noted. According to news articles secondary lahars from Cyclone Seroja destroyed homes, and impacted as many as 300, in several villages to the SW; mud-and-debris flows and flooding severely impacted other parts of Indonesia and killed at least 70 people. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 4 km away from the summit crater.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM); Reuters; South China Morning Post


24 March-30 March 2021 Citation IconCite this Report

PVMBG reported that the Strombolian eruption at Lewotolok continued during 24-30 March. Daily gray-and-white ash plumes rose as high as 800 m above the summit and drifted in different directions. Incandescent material was ejected 500 m above the summit on 23, 27, and 30 March, and 300 m above the summit on 25 March. On 26 and 28 March incandescence was observed up to 100 m above the summit, accompanied by incandescent ejecta as far as 350 m to the SE. The eruptive events were accompanied by rumbling and banging sounds. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


17 March-23 March 2021 Citation IconCite this Report

PVMBG reported that the Strombolian eruption at Lewotolok continued during 17-23 March. Daily gray-and-white ash plumes rose as high as 700 m above the summit and drifted mainly E and SE. Incandescent material was ejected 300 m E of the summit on 20 March. The next day incandescent material was ejected 100 m above the summit and as far as 200 m E. On 22 March explosions ejected incandescent material 250-350 m SE. The eruptive events were accompanied by rumbling and banging sounds. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 4 km away from the summit crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


10 March-16 March 2021 Citation IconCite this Report

PVMBG reported that the Strombolian eruption at Lewotolok continued during 10-16 March. Daily gray-and-white ash plumes rose as high as 1.5 km above the summit and drifted mainly E and SE. The eruptive events were accompanied by rumbling and banging sounds. Visual observations were hindered by weather on 10 March; each day during 11-16 March incandescent material was ejected as high as 500 m above the crater. Almost daily incandescent material was ejected 500-1,300 m E and SE from the crater. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 4 km away from the summer crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


3 March-9 March 2021 Citation IconCite this Report

PVMBG reported that the eruption at Lewotolok continued during 3-9 March; weather conditions sometimes hindered visual observations. Gray-and-white ash plumes rose 100-1,000 m above the summit and drifted E, SE, SW, and W. Incandescent material was ejected 300-800 m SE from the crater during 3-6 March. Rumbling and occasional thumping sounds were reported. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 4 km away from the summer crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


24 February-2 March 2021 Citation IconCite this Report

PVMBG reported that the eruption at Lewotolok continued during 24 February-2 March; weather conditions sometimes hindered visual observations. Gray-and-white ash plumes rose 100-700 m above the summit and drifted N, E, SE, and W. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 4 km away from the summer crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


17 February-23 February 2021 Citation IconCite this Report

PVMBG reported that the eruption at Lewotolok continued during 16-23 February; weather conditions sometimes hindered visual observations. Gray-and-white ash plumes rose 50-500 m above the summit and drifted E and SE. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 4 km away from the summer crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


10 February-16 February 2021 Citation IconCite this Report

PVMBG reported that the eruption at Lewotolo continued during 9-15 February. Gray-and-white ash plumes rose 400-1,000 m above the summit and drifted E and SE. Strombolian explosions ejected material 500 m SE on 13 February. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 4 km away from the summer crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


3 February-9 February 2021 Citation IconCite this Report

PVMBG reported that the eruption at Lewotolo continued during 3-9 February. Gray-and-white ash plumes rose 200-700 m above the summit and drifted E and SE. During 5-9 February Strombolian explosions ejected material 100-350 m above the summit and incandescent material was ejected 300-500 m SE from the crater. Rumbling and occasional banging sounds were reported. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 4 km away from the summer crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


27 January-2 February 2021 Citation IconCite this Report

PVMBG reported that the eruption at Lewotolo continued at least during 26-28 January. Gray-and-white ash plumes rose 500 m above the summit and drifted E, SE, and W. Strombolian explosions ejected material 500 m above the summit, and incandescent material was ejected as far as 500-600 m SE from the crater. Rumbling was reported during 29-30 January; weather conditions prevented visual observations of the crater during 29 January-2 February. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 4 km away from the summer crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


20 January-26 January 2021 Citation IconCite this Report

PVMBG reported that a Strombolian eruption at Lewotolo continued during 19-26 January. Gray-and-white ash plumes rose 200-1,000 m above the summit daily and drifted E, SE, and W. Rumbling sounds were occasionally reported. Strombolian explosions ejected material 100-600 m above the summit, and incandescent material was sometimes ejected as far as 500 m E, SE, and W from the crater. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 4 km away from the summer crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


13 January-19 January 2021 Citation IconCite this Report

PVMBG reported that a Strombolian eruption at Lewotolo continued during 13-19 January. Gray-and-white ash plumes rose 200-700 m above the summit daily and rumbling sounds were reported. Strombolian explosions ejected material 100-500 m above the summit, and incandescent material was ejected as far as 1.5 km SE from the crater. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 4 km away from the summer crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


6 January-12 January 2021 Citation IconCite this Report

PVMBG reported that a Strombolian eruption at Lewotolo continued during 6-12 January. Gray-and-white ash plumes rose 200-700 m above the summit and rumbling and banging sounds were reported. Incandescent material was ejected as far as 700 m SE from the crater during 6-8 January. Strombolian explosions ejected material 100-200 m above the summit crater on 7 January. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 4 km away from the summer crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


30 December-5 January 2021 Citation IconCite this Report

PVMBG reported that a Strombolian eruption at Lewotolo continued during 30 December-5 January. Gray-and-white ash plumes were visible daily, rising as high as 1 km above the summit. Rumbling and banging sounds were reported almost daily, and incandescent material was ejected as far as 1 km SE from the crater during 30-31 December and 4-5 January. Strombolian explosions ejected material 100-200 m above the summit crater during 1-5 January. The Alert Level was remained at 3 (on a scale of 1-4) and the public was warned to stay 4 km away from the summer crater.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM); Badan Nacional Penanggulangan Bencana (BNPB)


23 December-29 December 2020 Citation IconCite this Report

PVMBG reported that the eruption at Lewotolo continued during 23-29 December. Gray-and-white ash plumes were visible daily, rising as high as 1 km above the summit. Strombolian explosions were visible most nights ejecting material 100-300 m above the summit crater. Rumbling and banging noises were reported. Incandescent material was ejected as far as 1 km from the crater to the E and SE during 24-25 and 27-29 December. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 4 km away from the summer crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


16 December-22 December 2020 Citation IconCite this Report

PVMBG reported that the eruption at Lewotolo continued during 16-22 December. Gray-and-white ash plumes were visible daily, rising as high as 800 m above the summit. Strombolian explosions were visible most nights ejecting material 100-200 m above the summit crater. Rumbling was heard most days. The Alert Level was remained at 3 (on a scale of 1-4) and the public was warned to stay 4 km away from the summer crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


9 December-15 December 2020 Citation IconCite this Report

PVMBG reported that the eruption at Lewotolo continued during 9-15 December. Black, gray, and brown ash plumes were visible daily, rising as high as 1 km above the summit. Strombolian explosions were visible most nights ejecting material above the summit crater. The Alert Level was remained at 3 (on a scale of 1-4) and the public was warned to stay 4 km away from the summer crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


2 December-8 December 2020 Citation IconCite this Report

PVMBG reported that the eruption at Lewotolo continued during 1-8 December. Black-and-gray ash plumes were visible daily, rising as high as 1.5 km abo e the summit. Incandescence at the summit was visible nightly and material was sometimes ejected as high as 20 m above the summit. BNPB noted that by 5 December there were a total of 9,028 people housed in 11 evacuation centers. The Alert Level was remained at 3 (on a scale of 1-4) and the public was warned to stay 4 km away from the summit crater.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM); Badan Nacional Penanggulangan Bencana (BNPB)


25 November-1 December 2020 Citation IconCite this Report

According to PVMBG continuous tremor at Lewotolo began to be recorded at 1943 on 26 November, and a series of volcanic earthquakes began at 1947. A new eruption started at 0557 on 27 November, producing dense blackish gray ash plumes that rose 500 m above the summit and drifted W. Incandescence at the summit was visible, and the emissions turned white around 0630. Seismicity slightly decreased after the eruption, though continuous tremor persisted for a period of time. Dense white plumes rose as high as 400 m and nighttime incandescence was noted during 27-28 November.

During the morning of 29 November seismicity again increased, characterized by six deep volcanic earthquakes; continuous tremor appeared around 0930. At 0945 a 10-minute eruption sent dense gray-to-black ash plumes 4 km above the summit that drifted W and NW at lower heights and SE and E near the top of the plume. Ashfall was reported in several surrounding villages and video posted on social media showed tephra falling on roofs in residential areas. According to BNPB, Badan Penanggulangan Bencana Daerah (BPBD) evacuated almost 4,500 residents from 26 villages to seven evacuation centers. At 1300, the Alert Level was raised to 3 (on a scale of 1-4) and the public was warned to stay 4 km away from the summer crater.

Ash plumes continued to rise on at least six more occasions, and around 1900 Strombolian activity was visible. A pungent sulfur odor was noted at the Lewotolo observation post. Satellite data showed that a sulfur dioxide plume had drifted over the N half of Australia by 30 November. Ash plumes continued to be emitted during 30 November-1 December, with dense white-and-gray ash plumes rising 700-2,000 m above the summit. Lava flows near the summit were visible and incandescent material traveled down the flanks.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM); Badan Nacional Penanggulangan Bencana (BNPB); Advanced geospatial Data Management Platform (ADAM)


11 October-17 October 2017 Citation IconCite this Report

PVMBG reported that white plumes rose as high as 50 m above Lewotolo’s summit crater rim. The Alert Level remained at 2 (on a scale of 1-4).

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


4 October-10 October 2017 Citation IconCite this Report

The number of shallow and deep volcanic earthquakes at Lewotolo recently increased, prompting PVMBG to raise the Alert Level from 1 to 2 (on a scale of 1-4) on 7 October. The report noted that the public should not enter the 2-km-radius exclusion zone around the crater. Solfatara emissions rose as high as 500 m above the crater rim on 9 October; emissions during 1 August-6 October rose 50-600 m. BNPB reported that five earthquakes recorded by Badan Meteorologi, Klimatologi, dan Geofisika (BMKG) on 10 October ranged in magnitude between 3.9 and 4.9, and were located 10-30 km below Lewotolo. The events were felt by local populations, causing an evacuation of 723 people. Preliminary data suggested that five homes were damaged from rock avalanches, triggered by the earthquakes.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM); Badan Nacional Penanggulangan Bencana (BNPB)


25 January-31 January 2012 Citation IconCite this Report

On 25 January CVGHM lowered the Alert Level for Lewotolo from 3 to 2 (on a scale of 1-4) based on decreased seismicity and visual observations during 5-15 January. During 5-15 January fumarolic plumes rose 200-500 m above the summit and incandescence was observed.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


4 January-10 January 2012 Citation IconCite this Report

According to news articles, 500 people have evacuated their homes on 6 January because of increased activity at Lewotolo. Black smoke rose from the crater and rumbling sounds were reported. On 2 January CVGHM raised the Alert Level from 2 to 3 (on a scale of 1-4).

Sources: Jakarta Globe; BNO News


28 December-3 January 2012 Citation IconCite this Report

CVGHM reported that white plumes rose 50-250 m above the summit of Lewotolo during the month of December. Seismicity increased on 31 December and intensified on 2 January, the same day incandescence was observed. Based on visual and seismic observations, CVGHM raised the Alert Level from 1 to 2 (on a scale of 1-4) on 2 January, then later that day raised the Alert Level to 3.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


28 July-3 August 2004 Citation IconCite this Report

DVGHM stated that the pilot report of a plume emitted from Lewotolo on 25 June was false. Further investigation revealed that the emission was actually from Egon.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)


21 July-27 July 2004 Citation IconCite this Report

A pilot reported that a thin plume emitted from Lewotolo was at a height of ~300 m above the summit on 25 July. Ash was not visible on satellite imagery.

Source: Darwin Volcanic Ash Advisory Centre (VAAC)


Bulletin Reports - Index

Reports are organized chronologically and indexed below by Month/Year (Publication Volume:Number), and include a one-line summary. Click on the index link or scroll down to read the reports.

12/2011 (BGVN 36:12) December 2011-January 2012 seismicity, incandescence, and evacuations

09/2016 (BGVN 41:09) Thermal hotspots during 27 September-4 October 2015

02/2021 (BGVN 46:02) New eruption in late November 2020 consisting of ash plumes, crater incandescence, and ashfall




Information is preliminary and subject to change. All times are local (unless otherwise noted)


December 2011 (BGVN 36:12) Citation IconCite this Report

December 2011-January 2012 seismicity, incandescence, and evacuations

Plumes and seismic activity at Lewotolo volcano, Indonesia, increased during December 2011 and early January 2012. Lewotolo has erupted potassic calc-alkaline lavas containing as an accessary phase in vessicle fillings, the rare, complex zirconium-titanium-oxide mineral zirconolite (Ca0.8 Ce0.2 Zr Ti1.5 Fe2+0.3 Nb0.1 Al0.1 O7; de Hoog and van Bergen, 2000). Lewotolo last erupted in 1951. All historical eruptions were small (Volcanic Explosivity Index, VEI 2) with the exception of the first recorded eruption, which took place in 1660 and was as large as VEI 3. According to de Hoog and van Bergen (2000), strong fumarolic activity at the summit of Lewotolo indicates the presence and degassing of a shallow magma chamber.

December 2011-January 2012 activity increase. According to the Center of Volcanology and Geological Hazard Mitigation (CVGHM), Lewotolo produced thick white plumes reaching 50-250 m above the summit during December 2011. Seismicity increased on 31 December, and intensified on 2 January 2012 with tremor commencing at 1400. Accordingly, CVGHM raised the Alert Level from 1 to 2 (on a scale from 1-4) at 1800 on 2 January. Between 1800 and 2300 the same day, the maximum amplitude of recorded seismicity increased, and at 2000, incandescence was noticed at the summit.

At 2330 on 2 January, CVGHM increased the Alert Level to 3. Under the recommendation of CVGHM, access was prohibited within 2 km of Lewotolo (Hazard Zone III, figure 1), and residents in villages SE of the volcano were advised to keep vigilant and secure a safe place to flee to one of the towns to the N, W, or S in the event of an eruption.

Figure (see Caption) Figure 1. Map of areas around Lewotolo showing Hazards Zones I-III. Hazard Zone I includes areas possibly threatened by ash fall and incandescent bombs (within 7 km of Lewotolo, yellow dashed circle) and areas possibly affected by lahars (shaded yellow). Hazard Zone II includes areas possibly threatened by heavy ash-fall and incandescent bombs (within 4 km of Lewotolo, dark pink dashed circle) and areas possibly affected by pyroclastic flows, lava flows, and lava avalanches (shaded light pink). Hazard Zone III includes areas very likely to be threatened by heavy ash fall and incandescent bombs (within 2 km of Lewotolo, light pink dashed circle) and areas very likely to be affected by pyroclastic flows, lava flows, lava avalanches, and volcanic gases (shaded dark pink). Other symbols are explained in the legend at the right. Authorities prohibited access to Hazard Zone III on 2 January 2012. Modified from CVGHM.

Residents decide to evacuate. According to Antara News, evacuations began on 4 January spurred by increased activity of the previous few days, as well as minor ash falling in the villages. Antara News stated that most of the residents went to Lewoleba, the closest city to the volcano (~15 km to the SW of the summit). Of the evacuees in Lewoleba, all but about 50 people were reported to have found temporary housing with other residents of the city.

On 5 January, Channel 6 News reported that around 500 residents had evacuated leaving their homes in villages surrounding Lewotolo. They noted that residents who evacuated did so on their own accord, as the government had not yet called for evacuation. The Deputy District Chief of Lembata, Viktor Mado Watun, said "Black smoke columns are coming out of the mountain's crater, the air is filled with the smell of sulfur while rumbling sounds are heard around the mountain."

According to UCA News on 9 January, the health of the evacuees was cause for concern. Father Philipus da Gomez stated that "there are many refugees who have started suffering from acute respiratory infections."

Alert Level lowered. On 25 January 2012, CVGHM lowered the Alert Level of Lewotolo from 3 to 2 following decreased activity after 2 January. The lowered Alert Level restricted access to the summit craters only. CVGHM stated that the observed seismicity (table 1) showed a declining trend, tending towards normal conditions after 23 January. Visual observation revealed thick, white plumes reaching 400 m above the summit during 2-14 January (and a dim crater glow), and thin white plumes reaching no more than 50 m above the summit during 16-24 January (with no accompanying crater glow).

Table 1. Seismicity at Lewotolo during 3-24 January 2012, showing a declining trend in seismicity prior to CVGHM's lowering of the Alert Level from 3-2 on 25 January. Data courtesy of CVGHM.

Dates Hot-air blasts (avg./day) Shallow volcanic Deep volcanic Local tectonic Distant tectonic
03-07 Jan 2012 368 107 28 14 7
08-12 Jan 2012 349 4 5 2 2
13-17 Jan 2012 346 3 -- 3 --
18-22 Jan 2012 314 -- 1 7 3
23-24 Jan 2012 308 -- -- 4 1

On 15 January, direct observation of the crater was made, and revealed incandescence in solfataras, a weak sulfur smell, and hissing sounds in both the N and S side of the crater. CVGHM especially noted that the N side of the crater was quite different than when it was last observed in June 2010, when no solfataras were present. Differential Optical Absorption Spectroscopy (DOAS) measurements revealed fluctuating and increasing SO2 flux between 11-90 tons/day during 8-16 January.

References. de Hoog, J.C.M. and van Bergen, M.J., 2000, Volatile-induced transport of HFSE, REE, Th, and U in arc magmas: evidence from zirconolite-bearing vesicles in potassic lavas of Lewotolo volcano (Indonesia), Contributions to Mineralogy and Petrology, v. 139, no. 4, p. 485-502 (DOI: 10.1007/s004100000146).

Information Contacts: Center for Volcanology and Geological Hazard Mitigation (CVGHM), Jl. Diponegoro 57, Bandung, West Java, Indonesia, 40 122 (URL: http://www.vsi.esdm.go.id/); Channel 6 News (URL: http://channel6newsonline.com/); Antara News, Wisma ANTARA 19th Floor, Jalan Merdeka Selatan No. 17, Jakarta Pusat (URL: http://www.antaranews.com/); UCA News, Yayasan UCINDO, Gedung Usayana Holding, Lt.3, Jl. Matraman Raya No.87, Jakarta Timur 13140 (URL: http://www.ucanews.com/).


September 2016 (BGVN 41:09) Citation IconCite this Report

Thermal hotspots during 27 September-4 October 2015

During December 2011-January 2012, Lewotolo's seismic activity increased and the volcano produced thick, white plumes that rose as high as 250 m above the summit before subsiding (BGVN 36:12). Since that episode, no further activity was observed through 31 December 2016, except for several thermal anomalies during 27 September 2015-4 October 2015, as recorded by MODIS satellite instruments analyzed using the MODVOLC algorithm (figure 2).

Figure (see Caption) Figure 2. The MODIS/MODVOLC composite image that indicates the location of thermal anomalies at Lewotolo between 27 September and 4 October 2015. One is N of the summit (27 September), the others are somewhat E. One of the two hotspots on 4 October appears on the E summit rim. The daily thermal alert maps indicated that the five hotspots were all weak.

Information Contacts: Hawai'i Institute of Geophysics and Planetology (HIGP), MODVOLC Thermal Alerts System, School of Ocean and Earth Science and Technology (SOEST), Univ. of Hawai'i, 2525 Correa Road, Honolulu, HI 96822, USA (URL: http://modis.higp.hawaii.edu/, http://modis.higp.hawaii.edu/).


February 2021 (BGVN 46:02) Citation IconCite this Report

New eruption in late November 2020 consisting of ash plumes, crater incandescence, and ashfall

Lewotolok (also known as Lewotolo) is located on the eastern end of a peninsula connected to Lembata (formerly Lomblen) that extends north into the Flores Sea. Eruptions date back to 1660, characterized by explosive activity in the summit crater. Typical activity has consisted of seismicity and thermal anomalies near the summit crater (BGVN 36:12 and 41:09). A new eruption that began in late November 2020 was characterized by increased seismicity, dense, gray ash plumes, nighttime crater incandescence, and ashfall. This report covers activity through January 2021 using information primarily from the Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM, or the Center of Volcanology and Geological Hazard Mitigation), MAGMA Indonesia, and satellite data.

Summary of activity during February 2012-October 2020. Activity from February 2012 to November 2020 was relatively low and consisted primarily of a persistent thermal anomaly in the summit crater since at least March 2016 and occasional white gas-and-steam emissions. During January 2012 intermittent white gas-and-steam plumes rose 15-500 m above the crater, accompanied by crater incandescence; no thermal anomalies were reported during 16-24 January. On 6 January there were 500 people in the Lembata district evacuated due to reports of ash plumes that were observed by local residents, the smell of sulfur, and the sound of rumbling (BGVN 36:12).

Thermal activity dates back to 13 October 2014 using MODIS data in MODVOLC satellite data (BGVN 41:09; figure 3). According to the MODVOLC algorithm, a total of seven thermal alerts were detected on 13 October 2014 (1), 27 September 2015 (1), 2, 3, and 4 (2) October 2015, and 5 November 2017 (1). The number of thermal alerts in both MODVOLC and Sentinel-2 satellite data had increased slightly in 2020 compared to 2018 and 2019, though cloud cover often prevented visual confirmation for the latter (figure 3). Sentinel-2 thermal satellite imagery captured occasional thermal anomalies in the summit crater during 2016-2019 (figure 4). White gas-and-steam plumes were intermittently reported from September 2017 through 2 March 2018 that rose as high as 500 m above the crater and drifted dominantly E and W, according to PVMBG.

Figure (see Caption) Figure 3. Graph comparing the number of thermal anomalies using MODVOLC alerts and Sentinel-2 satellite data for Lewotolok during January 2014-January 2021 for MODVOLC and 20 March 2016-January 2021 for Sentinel-2 thermal satellite data. Data courtesy of HIGP - MODVOLC Thermal Alerts System and Sentinel Hub Playground.

Brief seismicity, which included shallow and deep volcanic earthquakes was detected during October 2017. On 9 October 2017 PVMBG issued a VONA (Volcano Observatory Notice for Aviation) reporting that white gas-and-steam emissions rose 500 m above the crater. On 10 October BNPB (Badan Nacional Penanggulangan Bencana) reported that five earthquakes 10-30 km below Lewotolok and ranging in magnitude of 3.9-4.9 as recorded by Badan Meteorologi, Klimatologi, dan Geofisika (BMKG). These seismic events were felt by local populations and resulted in an evacuation of 723 people. The only activity reported between January 2018 and October 2020 was white gas-and-steam plumes that rose 5-100 m above the crater drifting primarily E and W and an occasional thermal anomaly in the summit crater (figure 4).

Figure (see Caption) Figure 4. Sentinel-2 thermal satellite imagery shows a thermal anomaly in the summit crater of Lewotolok during 20 March 2016 (top left), 8 July 2017 (top right), 13 July 2018 (bottom left), and 12 August 2019 (bottom right). Sentinel-2 satellite images with “Atmospheric penetration” (bands 12, 11, 8A) rendering. Courtesy of Sentinel Hub Playground.

New eruption starting in November 2020. On 26 November 2020 a continuous tremor began at 1943, followed by a series of volcanic earthquakes at 1947 and deep volcanic earthquakes at 1951, 1952, 1953, and 2255; white gas-and-steam emissions rose 20 m above the crater. Deep volcanic earthquakes were again recorded at 0242, 0537, 0556 on 27 November. At 0557 an explosion produced a gray ash plume that rose 500 m above the crater and drifted W; by 0630 the plume turned white, according to PVMBG (figure 5). Seismicity decreased slightly after the explosion, but tremor continued. During 27-28 November dense white gas-and-steam plumes rose as high as 500 m above the crater and nighttime crater incandescence was observed.

Figure (see Caption) Figure 5. Webcam image of a dense gray ash plume rising 500 m above the crater of Lewotolok on 27 November 2020. Courtesy of MAGMA Indonesia.

During the morning of 29 November seismicity increased again and consisted of six deep volcanic earthquakes, continuous tremor occurred around 0930. A second explosion was recorded at 0945 that produced an ash plume 4 km above the crater, accompanied by incandescent material that was ejected above the crater (figure 6). The ash plume consisted of two levels: the lower-level drifted W and NW and the upper-level drifted E and SE. The large, gray ash plume was captured in a satellite image as it spread generally E and W (figure 7). Ashfall and a sulfur odor was reported in several surrounding villages; videos from social media showed tephra falling onto the roofs of residential areas. BPBD evacuated residents in 28 villages in two sub-districts; by 29 November at 1300 about 900 people had been evacuated. At 1900 Strombolian activity was observed and during the night, crater incandescence was visible.

Figure (see Caption) Figure 6. Photos of the eruption at Lewotolok on 29 November 2020 that produced a dense, gray ash plume 4 km above the crater. Courtesy of Devy Kamil Syahbana, PVMBG (left) and MAGMA Indonesia (right).
Figure (see Caption) Figure 7. Satellite image showing a strong gray ash plume above Lewotolok on 29 November 2020, expanding roughly E and W. Courtesy of Sentinel Hub Playground and the European Space Agency, Copernicus.

The eruption continued from 29 November into 1 December, where the white-and-gray ash plumes rose 700-2,000 m above the crater and drifted SE and W, accompanied by incandescent material that was ejected above the crater and the smell of sulfur, according to PVMBG (figure 8). A large sulfur dioxide plume was reported drifting SE and extending over the N half of Australia by 30 November (figure 9). By 1300 that day, 4,628 people had been evacuated. Incandescent lava flows near the summit were visible and incandescent material traveled down the flanks during 30 November and 1 December.

Figure (see Caption) Figure 8. Webcam image of the continuous eruption at Lewotolok showing a dense gray ash plume rising above the cloud-covered summit on 30 November 2020. Courtesy of MAGMA Indonesia.
Figure (see Caption) Figure 9. SO2 plume from Lewotolok captured by the Sentinel-5P/TROPOMI instrument on 30 November 2020 drifting SE and along the N part of Australia. Courtesy of Simon Carn and the NASA Global Sulfur Dioxide Monitoring Page.

White-and-gray plumes continued frequently through January 2021, rising 100-1,500 m above the crater, drifting in multiple directions, accompanied by nighttime crater incandescence and occasional incandescent ejecta (figure 10). During 1-8 December gray plumes rose 100-1,000 m above the crater and drifted E, W, and SW accompanied by nightly crater incandescence and incandescent material ejected as high as 20 m above the crater. By 5 December at 2200 about 9,028 residents had been evacuated to 11 evacuation centers, according to BNPB. Black, gray, and brown ash plumes were visible daily during 9-15 December, rising 1 km above the crater, accompanied by nightly Strombolian explosions that ejected material above the crater. More Strombolian explosions on most nights over 16-29 December ejected material 100-300 m above the crater; in addition, the sounds of rumbling and banging could be heard. The material was deposited as far as 1 km from the crater E and SE during 24-25 and 27-31 December and 4-7 January 2021. Strombolian activity continued into January, accompanied by frequent gray-and-white ash plumes, rumbling and banging sounds, and incandescent ejecta up to 600 above the crater that extended as far as 500 m E, SE, and W. Crater incandescence was visible up to 600 m above the crater.

Figure (see Caption) Figure 10. Webcam images showing continuing dense gray ash plumes from Lewotolok on 1 December 2020 (top) and 8 January 2021 (bottom). Courtesy of MAGMA Indonesia.

A consistent level of thermal activity was recorded in the Sentinel-2 MODIS Thermal Volcanic Activity from February 2019 through October 2020; in early December 2020 a slight increase in thermal anomalies were detected (figure 11). This data reflects the start of the new eruption in late November 2020. According to the MODVOLC thermal algorithm, five thermal hotspots were detected between January 2020 and January 2021 on 3 September (1), 29 November (2), 24 December (1), and 5 January 2021 (1). Some of this thermal activity was also observed in Sentinel-2 thermal satellite imagery in the summit crater (figure 12).

Figure (see Caption) Figure 11. Sentinel-2 MODIS Thermal Volcanic Activity data (bands 12, 11, 8A) shows consistent thermal activity (red dots) at Lewotolok during February 2020 through December 2020. Stronger thermal anomalies in early December is likely due to the new eruption that began in late November 2020. Courtesy of MIROVA.
Figure (see Caption) Figure 12. Sentinel-2 thermal satellite imagery showing a thermal anomaly in the summit crater of Lewotolok on 25 October (top left), 9 November (top right), and 3 January 2021 (bottom right). On 14 December (bottom left) a Natural Color image showed a gray ash emission above the clouds and drifted E. On 3 January 2021 (bottom right) two thermal anomalies were visible in the summit crater accompanied by gas-and-steam emissions drifting NE. Sentinel-2 satellite images with “Natural Color” rendering (bands 4, 3, 2) on 14 December 2020, all other images use “Atmospheric penetration” (bands 12, 11, 8A) rendering. Courtesy of Sentinel Hub Playground.

Information Contacts: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as Indonesian Center for Volcanology and Geological Hazard Mitigation, CVGHM), Jalan Diponegoro 57, Bandung 40122, Indonesia (URL: http://www.vsi.esdm.go.id/); Badan Nasional Penanggulangan Bencana (BNPB), National Disaster Management Agency, Graha BNPB - Jl. Scout Kav.38, East Jakarta 13120, Indonesia (URL: http://www.bnpb.go.id/); MAGMA Indonesia, Kementerian Energi dan Sumber Daya Mineral (URL: https://magma.vsi.esdm.go.id/); 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/); Hawai'i Institute of Geophysics and Planetology (HIGP) - MODVOLC Thermal Alerts System, School of Ocean and Earth Science and Technology (SOEST), Univ. of Hawai'i, 2525 Correa Road, Honolulu, HI 96822, USA (URL: http://modis.higp.hawaii.edu/); Sentinel Hub Playground (URL: https://www.sentinel-hub.com/explore/sentinel-playground); European Space Agency (ESA), Copernicus (URL: http://www.esa.int/Our_Activities/Observing_the_Earth/Copernicus); NASA 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/); Simon Carn, Dept of Geological and Mining Engineering and Sciences, Michigan Technological University, 1400 Townsend Dr., Houghton, MI 49931, USA (URL: https://so2.gsfc.nasa.gov/).

This compilation of synonyms and subsidiary features may not be comprehensive. Features are organized into four major categories: Cones, Craters, Domes, and Thermal Features. Synonyms of features appear indented below the primary name. In some cases additional feature type, elevation, or location details are provided.

Eruptive History

There is data available for 10 Holocene eruptive periods.

Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
2020 Nov 27 2021 Jun 24 (continuing) Confirmed 2 Historical Observations
2012 Jan 2 2012 Jan 14 Confirmed 1 Historical Observations Summit
1951 Dec 15 Unknown Confirmed 2 Historical Observations
1920 Unknown Confirmed 2 Historical Observations
1899 Jun 2 Unknown Confirmed 2 Historical Observations
1864 Unknown Confirmed 2 Historical Observations
1852 Oct 5 1852 Oct 6 Confirmed 2 Historical Observations K2 crater
1849 Oct 6 Unknown Confirmed 2 Historical Observations
1819 Unknown Confirmed 2 Historical Observations
1660 Unknown Confirmed 3 Historical Observations
Deformation History

There is no Deformation History data available for Lewotolok.

Emission History

There is no Emissions History data available for Lewotolok.

Photo Gallery

Lewotolo volcano, rising here above the village of Jontona, anchors the eastern end of the northern peninsula that is connected to Lembata (formerly Lomblen) Island by a narrow isthmus. The symmetrical stratovolcano contains a small cone with a 130-m-wide crater constructed at the SE side of a larger crater that forms the volcano's summit. Many lava flows have reached the coastline. Historical eruptions, recorded since 1660, have consisted of explosive activity from the summit crater.

Photo by Kasturian, 1981 (Volcanological Survey of Indonesia).
Lewotolo, seen here from the Flores Sea NW of the volcano, anchors the eastern end of the northern peninsula that is connected to Lomblen Island by a narrow isthmus. Many lava flows have reached the coastline of the peninsula. Historical eruptions from Lewotolo have been recorded since 1660 and have consisted of explosive activity from the summit crater.

Photo by Rob McCaffrey, 1982 (Rensselaer Polytechnic Institute).
Four volcanoes are seen in this NASA International Space Station image (with north to the upper left) of Solor (lower left), Adonara (upper left), and Lembata (right) Islands. Ililabalekan volcano on SW Lembata (formerly Lomblen) Island is the only one of these without historical eruptions, although fumaroles are found near its summit. A satellitic cone was constructed on the SE flank of the steep-sided volcano, and four craters, one of which contains a lava dome and two small explosion pits, occur at the summit of Mount Labalekan.

NASA International Space Station image ISS009-E-7480, 2004 (http://eol.jsc.nasa.gov/).
The approximately 800-m-diameter Lewotolo summit crater is in the center of this July 2019 Planet Labs satellite image monthly mosaic (N is at the top). A smaller cone with a 100-m-wide crater has formed along the main crater rim. Lighter colored deposits are seen at the summit area and erosion has formed gullies down the flanks.

Satellite image courtesy of Planet Labs, 2019.
GVP Map Holdings

The maps shown below have been scanned from the GVP map archives and include the volcano on this page. Clicking on the small images will load the full 300 dpi map. Very small-scale maps (such as world maps) are not included. The maps database originated over 30 years ago, but was only recently updated and connected to our main database. We welcome users to tell us if they see incorrect information or other problems with the maps; please use the Contact GVP link at the bottom of the page to send us email.


Title: Geology of Australia
Publisher: BMR, Geology & Geophysics, Dept Natural Resources
Country: Australia
Year: 1976
Map Type: Geology
Scale: 1:2,500,000
Map of Geology of Australia

Title: Australia, Indonesia
Publisher: DMA & Defence Department, AIS, Melbourne,Australia
Country: Indon, Australia
Year: 1971
Series: ONC
Map Type: Topographic
Scale: 1:1,000,000
Map of Australia, Indonesia

Title: Ende
Publisher: Director of Military Survey, UK
Country: Indonesia
Year: 1970
Series: 1501
Map Type: Topographic
Scale: 1:250,000
Map of Ende

Title: Pulau Lomblen
Publisher: Director of Military Survey, UK
Country: Indonesia
Year: 1970
Series: 1501
Map Type: Topographic
Scale: 1:250,000
Map of Pulau Lomblen

Title: Riangeba
Publisher: US Army Corps of Engineers
Country: Indonesia
Year: 1945
Series: T551
Map Type: Topographic
Scale: 1:250,000
Map of Riangeba

Title: Koepang
Publisher: US Army Map Service
Country: Indonesia
Year: 1944
Series: AMS
Map Type: Topographic
Scale: 1:1,000,000
Map of Koepang

Title: Boetoeng
Publisher: US Army Map Service
Country: Indonesia
Year: 1944
Series: AMS
Map Type: Topographic
Scale: 1:1,000,000
Map of Boetoeng

Title: Maoemere
Publisher: US Army Corps of Engineers
Country: Indonesia
Year: 1943
Series: T551
Map Type: Topographic
Scale: 1:250,000
Map of Maoemere
Smithsonian Sample Collections Database

There are no samples for Lewotolok in the Smithsonian's NMNH Department of Mineral Sciences Rock and Ore collection.

External Sites