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Lewotobi

Photo of this volcano
  • Indonesia
  • Sunda Volcanic Arc
  • Composite | Stratovolcano(es)
  • 2024 CE
  • Country
  • Volcanic Province
  • Landform | Volc Type
  • Last Known Eruption
  • 8.542°S
  • 122.775°E

  • 1,703 m
    5,587 ft

  • 264180
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

Most Recent Weekly Report: 10 July-16 July 2024 Citation IconCite this Report

Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity at Lewotobi Laki-laki continued during 10-16 July. Emissions rose 50-1,000 m above the summit during each day; emissions were described as white and gray on 10, 12, and 16 July, and gray on 11 and 13-15 July. Seismicity included frequent gas emission signals, volcanic earthquakes, rockfall events, low-frequency (LF) earthquakes, and 5-8 daily explosive events. The Alert Level remained at 3 (the second highest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 3-km radius around both Laki-laki and Perempuan craters, 4 km to the NNW and SSE of Laki-laki.

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


Most Recent Bulletin Report: December 2015 (BGVN 40:12) Citation IconCite this Report

Occasional increases in seismicity and white plumes during August 2011-October 2015

Lewotobi is composed of the Lewotobi Lakilaki (man) and Lewotobi Perempuan (woman) stratovolcanoes, with summit craters less than 2 km apart on Flores Island (figure 2). The last explosive eruption occurred in May 2003, accompanied by a high level of seismicity (BGVN 28:10). The volcano was apparently quiet through the middle of 2011, except for a brief period of unrest in May 2008 (BGVN 34:01) and March 2009 (BGVN 34:04). The report reviews activity through 7 October 2015, mostly from Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reports unless otherwise noted.

Figure (see Caption) Figure 2. Satellite image from 4 September 2013 showing Lewotobi volcano and associated features on eastern Flores Island: the two stratovolcanoes Lakilaki and Perempuan, and SE flank cone Iliwokar. The crater on the smaller Lakilaki edifice to the NW is 400 m wide, while Perempuan's is 700 m wide. Courtesy of Google Earth; data labels provided by GVP.

Seismicity increased during 26-31 August 2011, and plumes of "smoke" rose 15-50 m above the Perampuan crater rim. Based on the seismic data, the Alert Level for that crater was raised to 2 (Caution) (on a scale of 1-4) on 31 August. Increased seismicity and visual observations at Lakilaki after 17 September 2011 prompted PVMBG to raise the Alert Level to 2 for that cone as well on 22 September. Diffuse white plumes rose 15 m above the crater. At Alert Level 2 people are prohibited from going within a 1-km radius of the respective volcano.

Diffuse white plumes again rose 15-25 m above the summits of both craters during January-March 2012. Seismicity at both fluctuated, but had declined overall during September 2011-March 2012. The Alert Level at both was reduced from 2 to 1 (Normal) on 29 March 2012. Another period of increased seismicity on 28 September 2013 prompted PVMBG to again raise the Alert Level of Perempuan to 2.

Based on analysis of satellite images and wind data, the Darwin Volcanic Ash Advisory Centre (VAAC) reported that on 6 October 2014 a narrow, low-level ash plume from Lewotobi rose to an altitude of 3 km and drifted 185 km WNW. However, PVMBG did not report activity of any kind or raise the Alert Level. MODVOLC thermal alert pixels for that date showed a broad area on the E flank with 15 scattered anomalies extending to the shoreline, and three pixels the day before located just SE (figure 3). An alternate hypothesis is that fires spread NW due to prevailing winds, sending a low-level plume in that direction.

Figure (see Caption) Figure 3. MODVOLC maps showing thermal alert pixels at Lewotobi on 5 October (left) and 6 October (right) 2014. Courtesy of Hawai'i Institute of Geophysics and Planetology (HIGP), MODVOLC Thermal Alerts System.

White plumes were reported by PVMBG to be rising 15-20 m above Lakilaki during periods of clear weather from 1 February to 17 March 2015. Seismicity increased significantly on 13 March, especially the number of volcanic earthquakes and shallow volcanic earthquakes; harmonic tremor, tornillo events, and tectonic events were also detected. On 17 March the Alert Level was raised to 2. On 7 October 2015, PVMBG lowered the Alert Level to 1, based on visual observations and decreased seismicity over the previous three months.

Clear weather revealed white plumes rising 15 m above Perempuan during 17 July-25 August and 1 September-6 October 2015. Though the Alert Level had been raised on an unreported day, seismicity declined significantly after 1 August, and on 27 August, the Alert Level was lowered to 1.

Information Contacts: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM, Center for Volcanology and Geological Hazard Mitigation), Jl. Diponegoro 57, Bandung, West Java, Indonesia, 40 122 (URL: http://www.vsi.esdm.go.id/); 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/); 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/).

Weekly Reports - Index


2024: January | February | March | April | May | June | July
2023: December
2015: March | August | October
2014: October
2012: March
2011: August | September
2009: March
2008: May
2003: June | July | August | October
2002: October


10 July-16 July 2024 Citation IconCite this Report

Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that eruptive activity at Lewotobi Laki-laki continued during 10-16 July. Emissions rose 50-1,000 m above the summit during each day; emissions were described as white and gray on 10, 12, and 16 July, and gray on 11 and 13-15 July. Seismicity included frequent gas emission signals, volcanic earthquakes, rockfall events, low-frequency (LF) earthquakes, and 5-8 daily explosive events. The Alert Level remained at 3 (the second highest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 3-km radius around both Laki-laki and Perempuan craters, 4 km to the NNW and SSE of Laki-laki.

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


3 July-9 July 2024 Citation IconCite this Report

PVMBG reported that eruptive activity at Lewotobi’s Laki-laki volcano continued during 3-9 July. Multiple daily gray or white-and-gray ash plumes that were sometimes dense rose 50-1,000 m above the summit and drifted SW, W, and NW. According to a news article a series of three black-to-gray ash plumes with increasing intensity occurred on 3 July; the first two plumes rose 700 m and 800 m, and the third, recorded at 1356, rose 3 km. The plumes drifted E, NW, W, and SW. The Alert Level remained at 3 (the second highest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 3-km radius around both Laki-laki and Perempuan craters, 4 km to the NNW and SSE of Laki-laki.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM); Antara News


26 June-2 July 2024 Citation IconCite this Report

PVMBG reported that eruptive activity at Lewotobi’s Laki-laki volcano continued during 26 June-2 July. Multiple daily gray or white-and-gray ash plumes that were sometimes dense rose 50-1,000 m above the summit and drifted SW, W, and NW. An eruptive event that began at 1421 on 29 June lasted 10 minutes and 14 seconds based on the seismic data and produced a dense ash plume that rose around 900 m above the summit and drifted SW and W. According to a news article the Frans Seda Maumere Airport (60 km WSW) canceled flights from Kupang to Maumere on 2 July, though cancellations may have also occurred during the previous two days. Ashfall continued to impact residents in areas to the S and SW including Hokeng Jaya (4 km NW), Klatanlo (5 km NW), Persiapan Padang Pasir, Boru (8 km WNW), Pululera (6 km NW), Goloriang, Wotupudor, and Kumaebang. The Alert Level remained at 3 (the second highest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 3-km radius around both Laki-laki and Perempuan craters, 4 km to the NNW and SSE of Laki-laki.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM); Antara News; Antara News


19 June-25 June 2024 Citation IconCite this Report

PVMBG reported that eruptive activity at Lewotobi’s Laki-laki volcano continued during 19-25 June. Daily gray or white-and-gray ash plumes rose 100-1,000 m above the summit and drifted SW, W, and NW. According to news articles PVMBG noted that activity remained at high levels and 5-7 intense eruptive events were recorded daily during 16-22 June. Seismicity indicated that magma continued to move to the surface. According to news articles, recent ashfall had contaminated water resources downwind, significantly impacting residents of Dulipali (6 km NNW) in the Ile Bura District and Hokeng Jaya (4 km NW), Klatanlo (5 km NW), Persiapan Padang Pasir, Persiapan Nawokote B, Boru (8 km WNW), Nawokote (5 km W), and Pululera in Wulanggitang District; tanks of clean water were distributed on 23 June. Ashfall was reported in Hikong (15 km W) and Timutawa (15 km WNW), and in agricultural areas in the Taliura District on 22 June, and caused decreased visibility in areas along the Trans-Flores-Highway between Maumere (62 km W) and Larantuka (35 km NE), and in the Wagte and Lela districts. Ashfall on 25 June again impacted residents of Hikong and Timutawa and covered agricultural fields. The Alert Level remained at 3 (the second highest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 3-km radius around both Laki-laki and Perempuan craters, 4 km to the NNW and SSE of Laki-laki.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM); Metro TV News; Metro TV News; Metro TV News; Metro TV News


12 June-18 June 2024 Citation IconCite this Report

PVMBG reported that eruptive activity at Lewotobi’s Laki-laki volcano continued during 12-18 June. Multiple eruptive events were recorded daily by the seismic network daily. Daily gray or white-and-gray ash plumes rose 100-1,000 m above the summit and drifted SW, W, and NW. According to news articles ashfall was reported during 12-13 June in villages to the NW and NE, including Klatanlo (5 km NW), Hokeng Jaya (4 km NW), Persiapan Padang Pasir, Nawokote (5 km W), and Boru (8 km WNW) in the Wulanggitang District, along with Nobo (5 km NE) and Dulipali (6 km NNW) in the Ile Bura District. Workers sprayed water on several streets to wash off the ashfall. On 15 June ashfall was reported in areas to the SW including the communities of Padang Pasir, Wotupudor, and Kumaebang, and in Boru village. On 16 June ashfall affected the Frans Seda Sikka (60 km WSW) and Haji Hasan Aroeboesman Ende (126 km WSW) airports, causing disruptions to flights at Frans Seda Sikka. The Alert Level remained at 2 (the second lowest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 2-km radius around Laki-laki crater, 3 km to the NNE, and 5 km on the NE flanks.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM); Antara News; Antara News; Antara News


5 June-11 June 2024 Citation IconCite this Report

PVMBG reported that eruptive activity at Lewotobi’s Laki-laki volcano increased during 26 May-9 June. Eruptive activity increased daily, and ash-and-steam plumes became taller, rising 100-900 m above the summit on average and drifting in multiple directions; dense ash emissions rose 1-1.1 km above them summit on 5 and 9 June. The number of volcanic earthquakes as well as earthquake signals indicating eruptive events and avalanches significantly increased. PVMBG noted that there was also a significant increase in other types of seismic signals, though those increases were unrelated to the eruption; repairs and changes to the seismic network resulted in better detection of seismic signals. Incandescence at the summit was visible in a 5 June webcam image, and Strombolian activity was periodically visible on 9 June. At 0900 on 10 June the Alert Level was raised to 3 (the second lowest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 3-km radius around Laki-laki crater, 4 km to the NNE, and 5 km on the NE flanks. Strombolian activity continued on 10 June and several ash emissions rose 600-1,000 m above the summit. Gray ash emissions rose 300-600 m above the summit and drifted SW and W on 11 June.

The lava flows on the NE flank advanced 20 m during 29 February-9 April to a total length of 4.34 km; the advancement was due to gravitational forces and not eruptive activity, and no additional advancement had been recorded since.

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


29 May-4 June 2024 Citation IconCite this Report

PVMBG reported that eruptive activity at Lewotobi’s Laki-laki volcano continued during 29 May-4 June. White steam-and-gas plumes rose as high as 150 m above the summit and drifted W and SW during 29-30 May; emissions were not observed on 31 May. White, gray, and brown ash plumes rose 100-900 and drifted SW and W during 1-3 June, and ash plumes rose as high as 900 m on 4 June. The Alert Level remained at 2 (the second lowest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 2-km radius around Laki-laki crater, 3 km to the NNE, and 5 km on the NE flanks.

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


22 May-28 May 2024 Citation IconCite this Report

PVMBG reported that eruptive activity at Lewotobi’s Laki-laki volcano continued during 22-28 May. Gray-and-white ash plumes rose 100-800 m above the summit and drifted N, SW, and W during 22-25 May. White steam-and-gas plumes rose as high as 100 m above the summit and drifted W and SW during 26-27 May. The seismic network recorded daily eruptive events during 23-28 May, though there was no visual confirmation. The Alert Level remained at 2 (the second lowest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 2-km radius around Laki-laki crater, 3 km to the NNE, and 5 km on the NE flanks.

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


15 May-21 May 2024 Citation IconCite this Report

PVMBG reported that eruptive activity at Lewotobi’s Laki-laki volcano continued during 15-21 May. White steam-and-gas plumes rose as high as 100 m above the summit and drifted NW, W, and SW during 15, 17-18, and 21 May. Gray-and-white ash plumes rose 100 m above the summit and drifted W, SW, and NE during 16 and 19-20 May. The Alert Level remained at 2 (the second lowest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 2-km radius around Laki-laki crater, 3 km to the NNE, and 5 km on the NE flanks.

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


8 May-14 May 2024 Citation IconCite this Report

PVMBG reported that an eruption at Lewotobi’s Laki-laki volcano continued during 8-14 May. White steam-and-gas plumes rose 50-150 m above the summit and drifted in multiple directions during 8-9 and 12 May; eruptive events were occasionally recorded during those days though emission details were unknown. Gray-to-white ash plumes rose 50-200 m above the summit and drifted SW and W during 10-11 and 13-14 May. The Alert Level remained at 2 (the second lowest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 2-km radius around Laki-laki crater, 3 km to the NNE, and 5 km on the NE flanks.

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


1 May-7 May 2024 Citation IconCite this Report

PVMBG reported that gray-to-white ash plumes rose 100-500 m above the summit of Lewotobi’s Laki-laki volcano and drifted in multiple directions during 30 April-5 May. The plumes were sometimes dense. Eruptive events were recorded by the seismic network on 6 May, though no emissions were reported. The Alert Level remained at 2 (the second lowest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 2-km radius around Laki-laki crater, 3 km to the NNE, and 5 km on the NE flanks.

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


24 April-30 April 2024 Citation IconCite this Report

PVMBG reported that during 24-25 and 27 April white steam-and-gas plumes rose as high as 100 m above the summit of Lewotobi’s Laki-laki volcano and drifted W and SW. On 28 April white-and-gray ash plumes rose 100-300 m and drifted SW and W. Emissions were not observed on 26 April. The Alert Level remained at 2 (the second lowest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 2-km radius around Laki-laki crater, 3 km to the NNE, and 5 km on the NE flanks.

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


17 April-23 April 2024 Citation IconCite this Report

PVMBG reported that during 17-18 and 20-22 April white steam-and-gas plumes rose as high as 100 m above the summit of Lewotobi’s Laki-laki volcano and drifted N, NE, and E. On 23 April a white-and-gray ash plume rose 100-200 m and drifted SW and W. The Alert Level remained at 2 (the second lowest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 2-km radius around Laki-laki crater, 3 km to the NNE, and 5 km on the NE flanks.

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


10 April-16 April 2024 Citation IconCite this Report

PVMBG reported that on 11 and 14 April white-and-gray plumes rose 100-500 m above the summit of Lewotobi’s Laki-laki volcano and drifted N and E. White plumes rose as high as 150 m above the summit and drifted in multiple directions during 10, 12-13, and 15-16 April. Incandescence at the summit was visible in a 14 April webcam image. An eruptive event was recorded on 15 April, though no emissions were observed, possibly due to weather conditions. The Alert Level remained at 2 (the second lowest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 2-km radius around Laki-laki crater, 3 km to the NNE, and 5 km on the NE flanks.

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


3 April-9 April 2024 Citation IconCite this Report

PVMBG reported that white-and-gray plumes rose 50-200 m above the summit of Lewotobi’s Laki-laki volcano and drifted N, NE, and E on 6 and 9 April. White plumes rose as high as 300 m above the summit and drifted in multiple directions on 3, 5, and 7 April; no plumes were visible on 4 April. The Alert Level remained at 2 (the second lowest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 2-km radius around Laki-laki crater, 3 km to the NNE, and 5 km on the NE flanks.

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


27 March-2 April 2024 Citation IconCite this Report

PVMBG reported that white-and-gray plumes rose 100-500 m above the summit of Lewotobi’s Laki-laki volcano during 29-30 March. White plumes rose 20-50 m above the summit and drifted N and NE on 27 March; no plumes were visible on 28 and 31 March and during 1-2 April. PVMBG lowered the Alert Level to 2 (the second lowest level on a scale of 1-4) at 1900 on 1 March and the public was warned to stay outside of the exclusion zone, defined as a 2-km radius around Laki-laki crater, 3 km to the NNE, and 5 km on the NE flanks.

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


20 March-26 March 2024 Citation IconCite this Report

Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that white emissions rose as high as 100 m above the summit of Lewotobi Laki-laki during 20-26 March. Some rockfall events were detected by the seismic network. There were no visual observations of renewed lava effusion, and no reports of lava flow movement since 20 February. The Alert Level remained at Level 2 (on a scale of 1-4), and the public was warned to remain outside of the hazard zone, defined as a 2-km radius around the crater, the 3-km NNE sector expansion, and the 5-km NE sector expansion; both sector expansions extend from the established 2-km hazard radius.

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


28 February-5 March 2024 Citation IconCite this Report

PVMBG reported that white plumes rose as high as 300 m above the summit of Lewotobi’s Laki-laki volcano during 28 February-5 March. According to a news article, seismicity and visual observations showed that activity decreased during 22-29 February. Drone footage indicated that the lava flow was cooling, and effusion had stopped, though the flow may continue to slowly advance due to gravity, the slope of the ground, and the high temperature. PVMBG lowered the Alert Level to 2 (the second lowest level on a scale of 1-4) at 1900 on 1 March and the public was warned to stay outside of the exclusion zone, defined as a 2-km radius around Laki-laki crater, 3 km to the NNE, and 5 km on the NE flanks.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM); Antara News


14 February-20 February 2024 Citation IconCite this Report

PVMBG reported that the eruption at Lewotobi’s Laki-laki volcano was ongoing during 13-20 February. The lava flow on the NE flank continued to be active, advancing 100 m during 3-20 February to a total length of 4.2 km. A drone overflight on 20 February confirmed the position of the end of the lava flow. White steam-and-gas plumes were visible during 13, 15, 17, and 19-20 February rising as high as 100 m above the summit and drifting N, NE, and W; no emissions were observed on 14 February. White-and-gray ash plumes rose as high as 600 m above the summit on 16 and 18 February and drifted N and NE. According to a news article, all evacuees had returned to their homes. The Alert Level remained at 3 (the second highest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 3-km radius around Laki-laki crater, 4 km to the NNE, and 5 km on the NE flanks.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM); Antara News; Antara News


7 February-13 February 2024 Citation IconCite this Report

PVMBG reported that Lewotobi Laki-laki continued to erupt during 7-13 February. White emissions rose 30-700 m above the summit during 7 February, and 20–50 m above the summit during 8-11, and 13 February. A seismograph recorded eruptive events at 0807 on 7 February, 1858 on 9 February, 1806 on 10 February, and 1249 on 12 February. Dense, white to gray ash plumes rose 500-700 m above the summit and drifted N and NE during the eruptive events on 7 and 9 February. The Alert Level remained at 3 (the second highest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 4 km radius around Laki-laki crater, 5 km to the NNE, and 6 km on the NE flanks.

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


31 January-6 February 2024 Citation IconCite this Report

PVMBG reported that the eruption at Lewotobi’s Laki-laki volcano was ongoing during 31 January-6 February. Incandescence at the summit and from the lava flow on the NE flank was visible in webcam images during the week. On 31 January dense white-and-gray ash plumes rose as high as 700 m above the summit and drifted N and NE. At 0825 on 2 February a white-and-gray ash plume rose 700 m and drifted N and a pyroclastic flow descended the N flank as far as 500 m. An eruptive event was recorded at 1248 but it was not observed. At 1429 a dense white-and-gray ash plume rose as high as 1.5 km and drifted N. White steam-and-gas plumes were visible on the other days rising to 500 m above the summit and drifting N, NE, and S; no emissions were observed on 4 February. The Alert Level remained at 3 (the second highest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 4-km radius around Laki-laki crater, 5 km to the NNE, and 6 km on the NE flanks.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM); Antara News; Antara News


24 January-30 January 2024 Citation IconCite this Report

PVMBG reported that the eruption at Lewotobi’s Laki-laki volcano had decreased during 23-29 January based on visual and instrumental data. The lava flow on the NE flank continued to advance, reaching a length of 4 km, though the rate of advancement had slowed by 23 January, possibly due to gentler topography, a decrease in the effusion rate, or a combination of both. A total of 11 pyroclastic flows were detected and traveled 1-2 km N, NNE, and NE, though average distances were closer to 1 km. Eruption plume heights decreased from an average of 1.5 km above the summit to 500 m. The seismic network recorded a total of 388 lava avalanches that traveled as far as 1.5 km N and NE. Sulfur dioxide emissions significantly decreased, and deformation data indicated deflation. Analysis of deep volcanic earthquakes and low-frequency earthquakes both indicated a decrease in the supply of magma to the surface. At 1200 on 29 January the Alert Level was lowered to 3 (the second highest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 4-km radius around Laki-laki Crater, 5 km to the NNE, and 6 km on the NE flanks.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM); Antara News


17 January-23 January 2024 Citation IconCite this Report

PVMBG reported that the eruption at Lewotobi’s Laki-laki volcano was ongoing during 16-23 January. Dense white-and-gray or white, gray, and brown ash plumes rose as high as 1.5 km above the summit and drifted NW, N, NE, and E. Lava flows from the summit crater continued down the N flank and were almost 3.8 km long by 23 January, according to a news article. Lava avalanches and pyroclastic flows occasionally descended the N, NW, and SW flanks during the week; lava avalanches traveled at most 2 km down the SW flank on 16 January. The Alert Level remained at 4 (the highest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 5-km radius around Laki-laki Crater and 6 km from the crater on the N and NE flanks.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM); Antara News; Antara News; Antara News; Antara News; Antara News


10 January-16 January 2024 Citation IconCite this Report

PVMBG reported that the eruption at Lewotobi’s Laki-laki volcano was ongoing during 10-16 January. Dense white-and-gray or white, gray, and brown ash plumes rose as high as 2 km above the summit and drifted N and NE. Lava flows from the summit crater continued to advance down the N flank and were about 2 km long by 11 January. Rumbling was reported on 13 January. On 14 January as many as four pyroclastic flows traveled up to 1 km down the NE, N, and NNW flanks and lava avalanches traveled 1.5-2 km down the NE flank, according to news articles. Incandescent avalanches of material and accompanying pyroclastic flows traveled as far as 1.5 km N on 15 January. Incandescent avalanches also traveled 2-3 km NE and 1 km NNE. The exclusion zone was increased to 5 km from the Laki-laki Crater and 6 km from the crater on the N and NE flanks during the evening of 16 January. The Alert Level remained at 4 (the highest level on a scale of 1-4).

Sources: Antara News; Antara News; Antara News; Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM); Antara News; Antara News


3 January-9 January 2024 Citation IconCite this Report

PVMBG reported that the eruption at Lewotobi’s Laki-laki volcano from a fissure on the upper NNW flank and from a vent on the upper SSE flank was ongoing during 3-9 January. White plumes rose 300-1,000 m above the summit and drifted SW and W during 3-5 December. During the rest of the week white-and-gray or gray-to-brown ash plumes rose 1-1.5 km above the summit and drifted NW, N, and NE. The ash plumes were sometimes dense.

Masks had been distributed in Hokeng Jaya, Pululera, Klatanlo, and Nawakote in the district of Wulanggitan and the village of Dulempari in the district of Bura after the eruption began in late December and residents were encouraged to wear them when outside to minimize ash inhalation. On 1 January as many as 1,185 residents of Boru Village and 328 residents in the Konga Village area self-evacuated to several other locations including relatives’ homes and evacuation posts. Ash fell in several areas in the Wulanggitan and Bura districts. Badan Penanggulangan Bencana Daerah (BPBD) East Flores Regency mobilized and provided residents with essentials including mobile kitchens, food, tents, and cleaned ash off roadways. By 4 January a total of 3,898 people had evacuated. The Frans Xavier Seda Airport in Sikka District closed on 1 January due to thick ash deposits on the runways; it remained closed as of 9 January.

Activity intensified during the evening of 9 January. Incandescent material was ejected from the summit and lava flows from the NNW-flank fissure descended the NW flank. At 2300 the Alert Level was raised to 4 (on a scale of 1-4) and the public was warned to stay 4 km away from the Perempuan and Laki-laki craters and an additional 5 km from the NNW flanks of Laki-laki.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM); Badan Nacional Penanggulangan Bencana (BNPB); Badan Penanggulangan Bencana Daerah Provinsi Jawa Timur (East Java BPBD); Directorate General Of Civil Aviation, Ministry Of Transportation Republic Of Indonesia


27 December-2 January 2024 Citation IconCite this Report

PVMBG reported that seismicity at Lewotobi had increased on 12 December and was followed by the emergence of “tornillo” earthquakes indicating fluid movement at depth. An eruption occurred on 23 December at Laki-laki and lasted about 24 minutes. A 160-m-long fissure on the upper NW flank was visible afterwards and it emitted dense white plumes that rose 300 m. At 0253 on 28 December an observer noted a dense white-and-gray ash plume that rose 1 km above the summit and drifted NW. On 1 January the amplitude of continuous tremors increased. A new vent opened along a fissure located on the upper SSE flank and produced a white, gray, and black ash plume that rose 1-1.5 km above the summit. The Alert Level was raised to 3 (on a scale of 1-4) at 1600 and the public was warned to stay 3 km away from the Perempuan and Laki-laki craters and an additional 4 km from the NNW and SSE flanks of Laki-laki. At 0454 on 2 January a gray-to-brown ash plume rose 1.5 km above the summit and drifted SW and W.

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


20 December-26 December 2023 Citation IconCite this Report

PVMBG reported that an eruption at Lewotobi’s Laki-laki, the NW of two large adjacent stratovolcanoes, occurred at 0714 on 23 December and lasted about 24 minutes. The Aviation Color Code was raised to Orange (the third level on a four-color scale). Dense gray ash plumes rose 1-1.5 km above the summit and drifted N. The eruption was preceded by about a week of increased seismicity. The Alert Level remained at 2 (on a scale of 1-4) and the public was warned to stay 2 km away from the active summit crater.

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


13 December-19 December 2023 Citation IconCite this Report

On 17 December seismicity at Lewotobi increased significantly, prompting PVMBG to raise the Alert Level to 2 (on a scale of 1-4). Seismicity had been increasing during the previous week and was characterized by greater numbers of both deep and shallow volcanic earthquakes, and the emergence of tornillo-type earthquakes which indicated fluid movement. The public was warned to stay 2 km away from the craters at each summit.

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


7 October-13 October 2015 Citation IconCite this Report

PVMBG reported that white plumes were observed rising 15 m above Lewotobi during periods of clear weather from 1 Septmber-6 October. Seismicity declined significantly during the previous three months and became stable. The Alert Level was lowered to 1 (on a scale of 1-4) on 7 October.

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


26 August-1 September 2015 Citation IconCite this Report

PVMBG reported that white plumes were observed rising 15 m above Lewotobi during periods of clear weather from 17 July to 25 August. Seismicity decreased significantly during 1-25 August. The Alert Level was lowered to 1 (on a scale of 1-4).

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


18 March-24 March 2015 Citation IconCite this Report

PVMBG reported that white plumes were observed rising 15-20 m above Lewotobi during periods of clear weather from 1 February to17 March. Seismicity increased significantly on 13 March, especially volcanic earthquakes and shallow volcanic earthquakes; harmonic tremor, Tornillo events, and tectonic events were also detected. On 17 March the Alert Level was raised to 2 (on a scale of 1-4). Residents and tourists were warned not to approach the craters within a 1-km radius.

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


1 October-7 October 2014 Citation IconCite this Report

Based on analysis of satellite images and wind data, the Darwin VAAC reported that on 6 October a narrow, low-level ash plume from Lewotobi rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 185 km WNW.

Source: Darwin Volcanic Ash Advisory Centre (VAAC)


28 March-3 April 2012 Citation IconCite this Report

CVGHM reported that seismicity at Lewotobi Lakilaki, one of two stratovolcanoes comprising Lewotobi, fluctuated but declined overall during 18 September 2011-25 March 2012. No significant changes were observed at the volcano. The Alert Level was lowered to 1 (on a scale of 1-4) on 29 March.

Observers of Lewotobi Perempuan, the second stratovolcano comprising Lewotobi, noted that during January-March diffuse white plumes rose 15 m above the crater and no significant changes had occurred. After 31 August 2011 through 25 March 2012 seismicity fluctuated but declined overall. On 29 March the Alert Level was lowered to 1.

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


21 September-27 September 2011 Citation IconCite this Report

CVGHM raised the Alert Level for Lewotobi Lakilaki, one of two stratovolcanoes composing Lewotobi, to 2 (on a scale of 1-4) on 22 September due to increased seismicity since 17 September and visual observations. Although no significant changes in the volcano were observed, diffuse white plumes rose 15 m above the crater. Visitors and residents were prohibited from going within a 1-km radius of Lewotobi Lakilaki.

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


31 August-6 September 2011 Citation IconCite this Report

CVGHM reported that during 26-31 August seismicity at Lewotobi increased. Plumes of "smoke" rose 15-50 m above the Lewotobi Perampuan crater rim; no other significant changes were visibly apparent. Based on the seismic data, the Alert Level was raised to 2 (on a scale of 1-4) on 31 August. Visitors and residents were advised not to approach the volcano within 1 km of the Lewotobi Perampuan crater.

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


18 March-24 March 2009 Citation IconCite this Report

On 23 March, CVGHM lowered the Alert Level for Lewotobi from 2 to 1 (on a scale of 1-4) based on visual observations and decreased seismicity during March. Rarely seen diffuse white plumes rose 25 m above the crater and drifted E. Visitors and residents were advised not to approach the crater.

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


28 May-3 June 2008 Citation IconCite this Report

On 29 May, CVGHM raised the Alert Level for Lewotobi to 2 (on a scale of 1-4) due to an increase in seismicity during 12-29 May. White plumes typically rose about 25 m above the crater and drifted E; visual observations indicated no changes.

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


29 October-4 November 2003 Citation IconCite this Report

A decrease in volcanic activity at Lewotobi during 13-19 October led DVGHM to decrease the Alert Level from 2 to 1 (on a scale of 1-4). Only gas was emitted to low levels and no volcanic earthquakes were recorded.

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


27 August-2 September 2003 Citation IconCite this Report

The Darwin VAAC reported that an eruption at Lewotobi on 1 September produced an ash plume to a height of ~2.5 km above the summit that drifted W. Volcanic material caused fires in forests within a 1 km radius of the crater and damaged crops on the volcano's flanks. VSI raised the Alert Level to 4, the highest level. According to news articles, hundreds of people from at least six villages fled their homes for the village of Konga to the E. By 2 September the Alert Level had been reduced to 3.

Sources: Agence France-Presse (AFP); Darwin Volcanic Ash Advisory Centre (VAAC)


2 July-8 July 2003 Citation IconCite this Report

Low-level ash emissions continued at Lewotobi during 2-29 June. During 2-8 June ash plumes reached ~300 m above the summit, and ash fell in the villages of Bawalatang, Duang, and Boru. Lewotobi remained at Alert Level 2 (on a scale of 1-4).

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


11 June-17 June 2003 Citation IconCite this Report

On 30 May at 1650 an ash explosion at Lewotobi Lakilaki, a stratovolcano of Lewotobi, sent an ash column to a height of ~200 m above the summit. Ash fell at the observatory post about 5 km from the crater. As of 1 June, Lewotobi was at Alert Level 2 (on a scale of 1-4).

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


9 October-15 October 2002 Citation IconCite this Report

On 12 October at 2330 there was an explosion at Lewotobi Lakilaki, a stratovolcano of Lewotobi, that was accompanied by a weak thundering sound. Ash fell as far as 5 km away and an ash column rose ~500 m above the volcano. According to VSI, eruptions at Lewotobi usually occur over an extended period of time, therefore they expect more explosions to take place in the next couple of weeks to months. On 16 October, Lewotobi was at Alert Level 4 (the highest level).

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


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.

04/1991 (BGVN 16:04) Brief increase in seismicity

05/1991 (BGVN 16:05) Ash emission follows increased seismicity

06/1991 (BGVN 16:06) Strombolian activity; ash to 300 m height; several hundred explosion earthquakes weekly

07/1991 (BGVN 16:07) Strombolian activity

11/1991 (BGVN 16:11) Continued gas emission

05/1999 (BGVN 24:05) March-May ash eruptions

07/1999 (BGVN 24:07) 1 July explosion ignites fires and up to 1 mm of ash falls on local villages

11/2002 (BGVN 27:11) Explosion on 12 October 2002, the first reported activity since July 1999

06/2003 (BGVN 28:06) Minor explosion and ashfall on 30 May

10/2003 (BGVN 28:10) Explosions and ashfall during June-July; seismicity stops in early September

01/2009 (BGVN 34:01) Increase in seismicity during May 2008; more details on 2003 eruption

04/2009 (BGVN 34:04) Drops in steaming and seismicity during March 2009

12/2015 (BGVN 40:12) Occasional increases in seismicity and white plumes during August 2011-October 2015




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


April 1991 (BGVN 16:04) Citation IconCite this Report

Brief increase in seismicity

A sudden increase in seismicity, from 7 to 60 earthquakes/day, was recorded at the end of March. Activity peaked on 26 March, then gradually decreased. No changes in surface activity were observed.

Information Contacts: W. Modjo, VSI.


May 1991 (BGVN 16:05) Citation IconCite this Report

Ash emission follows increased seismicity

Ash was erupted to 800 m height, and deposited to 7 km NE and 4 km NW, on 11-13 May. Gas emission continued through the end of May, with 84 emission events recorded during the last week. Twelve shallow and seven deep volcanic earthquakes were also recorded during the last week in May.

Information Contacts: W. Modjo, VSI.


June 1991 (BGVN 16:06) Citation IconCite this Report

Strombolian activity; ash to 300 m height; several hundred explosion earthquakes weekly

Explosions at the summit crater on 28 May at 1615, 1840, and 1911 produced ash clouds to 300 m, accompanied by thunder-like sounds heard 4 km SW of the crater (at Pos Observatory). Since then, activity has been dominated by gas emissions and explosion earthquakes (figure 1). Explosions emitted ash (12-19 times/week) to 100-300 m high. On 8 and 13 June, lapilli and bombs ejected by Strombolian activity covered the area surrounding the crater. Glow and lava fountaining then steadily diminished through the end of June. Explosion earthquakes were recorded 200-405 times/week, compared to 0-4 deep and shallow volcanic earthquakes, and 5-7 tectonic earthquakes/week. No tremor episodes were recorded.

Figure (see Caption) Figure 1. Daily number of earthquakes and explosion events at Lewotobi Lakilaki, May 1991. Arrows represent explosions. Courtesy of VSI.

Information Contacts: W. Modjo, VSI.


July 1991 (BGVN 16:07) Citation IconCite this Report

Strombolian activity

Press releases reported increased activity, with small eruptions occurring around 19 July. One eruption reportedly ejected incandescent material 100 m high, dropping hot ash (smelling of sulfur) onto nearby areas and causing residents to flee. At 1645 on 29 July, a 300-m-high ash cloud extending ~35 km W was reported by pilots on Qantas flight A61. By the week of 14-19 August the volcano was no longer exploding, and gas emissions, 50-100 m high, appeared to be decreasing.

Information Contacts: W. Modjo, VSI; ICAO; UPI.


November 1991 (BGVN 16:11) Citation IconCite this Report

Continued gas emission

Degassing has continued since October, sometimes punctuated by ash ejection reaching 50-150 m above the crater. The number of degassing earthquakes dropped slightly from 246 during the first week of December to 233 in the second week. One B-type volcanic earthquake was recorded during the two-week period.

Information Contacts: VSI.


May 1999 (BGVN 24:05) Citation IconCite this Report

March-May ash eruptions

The current phase of activity at Lewotobi Lakilaki began at 0547 on 21 March, when observers noted a vigorous steam plume rising 250 m above the summit. This was noteworthy because when the volcano is in a non-active phase its steam plume rises no higher than ~25 m. On 30 March a rumbling noise was heard and the volcano's status was raised to Level II, or "Alert." The following day observers twice noted ash plumes ~250 m high accompanied by a rumbling noise. On 1 April observers saw such plumes at three different times.

From 27 April to 3 May the ash eruption continued. The observed ash was whitish-gray, of weak to moderate pressure, and extending 300 m above the summit. Eruption events were sometimes accompanied by detonations. On 29 April, glowing material was ejected 50-75 m above the crater and it fell over an area with 50 m radius. Thin ash fell over the Boru area the following day at 1600. The seismic record totals for the week showed four volcanic type-B, nine tectonic, four eruption, and nine emission events.

Ash eruptions reached heights of 500 m during 4-10 May and were sometimes accompanied by strong detonations. On 7 and 9 May glowing materials were again ejected to 50-75 m heights, falling within a 50 m radius. On 7 May ash fell around the areas of Boru, Riang Boru, Hokeng, and Wolorona. Deposits were ~1 mm thick. Seismic events for the week decreased, with three eruptive and five emission events. From 11 through 17 May ash eruptions continued to reach heights of 500 m and were sometimes accompanied by strong detonations. During the week of 18-24 May emission heights decreased to 300 m and blast sounds became less frequent. Thin ash fell during 19 May on the Boru and Riagulu regions.

Information Contacts: Volcanological Survey of Indonesia (VSI), Jalan Diponegoro No. 57, Bandung 40122, Indonesia (URL: http://www.vsi.esdm.go.id/).


July 1999 (BGVN 24:07) Citation IconCite this Report

1 July explosion ignites fires and up to 1 mm of ash falls on local villages

Lewotobi Laki-Laki erupted at 1000 on 1 July. A strong blast accompanied the eruption. Glowing material fell in a 500 m radius to the N and S, igniting forest fires that extended 2.5 km N of the crater and 500 m S, to the ridge dividing Lewotobi Laki-Laki from Lewotobi Perempuan. Ash emissions reached 1,000 m above the summit and were distributed to the W, SW, and S. The emissions then drifted to the NW, W, SW, and S in an 8-km radius. The settlements of Boru, Bawalatang, and Watukubu reported ash deposits in the range 0.5-1 mm thick.

"White, thin-to-thick ash emissions" have continued since the initial eruption, rising ~100 m above the summit. Authorities raised the volcano status to "Level III" (prepare to evacuate) on 2 July. The seismic record for the week 29 June to 5 July reported 266 type-A, 70 type-B, two tectonic, and 31 explosive events.

Information Contacts: R. Sukhyar and Dali Ahmad, Volcanological Survey of Indonesia (VSI), Jalan Diponegoro No. 57, Bandung 40122, Indonesia (URL: http://www.vsi.esdm.go.id/).


November 2002 (BGVN 27:11) Citation IconCite this Report

Explosion on 12 October 2002, the first reported activity since July 1999

On 12 October 2002 at 2330, an explosion at Lewotobi Lakilaki (a twin stratovolcano of Lewotobi Perempuan) was accompanied by a weak thundering sound that was heard at Hokeng village, 5 km from the summit. An ash column rose ~500 m above the volcano and drifted NW. Ash fell as far as 5 km away, accumulating to thicknesses of less than 0.5 mm. No seismic data were available. Following the eruption, the Alert Level was raised to 2 (on a scale of 1-4). According to VSI, eruptions at Lewotobi usually occur over an extended time, therefore more explosions were expected in the following weeks to months. VSI reported no increase in volcanism in the weeks following the 12 October eruption. Through at least 24 November, a thin white low-pressure ash plume was frequently visible rising 150-250 m above the summit. Lewotobi remained at Alert Level 2.

Information Contacts: Dali Ahmad, Volcanological Survey of Indonesia (VSI), Jalan Diponegoro No. 57, Bandung 40122, Indonesia (URL: http://www.vsi.esdm.go.id/).


June 2003 (BGVN 28:06) Citation IconCite this Report

Minor explosion and ashfall on 30 May

An explosion on 12 October 2002 at Lewotobi Lakilaki, one of the twin stratovolcanoes that comprise Lewotobi, produced an ash column that rose ~500 m above the volcano (BGVN 27:11). Through at least 24 November, a "thin white low-pressure ash plume" rose 150-250 m above the summit.

No further reports were issued until May 2003, when the Volcanological Survey of Indonesia reported an explosion at 1650 on 30 May 2003. The resulting ash column reached 200 m above the summit and caused ashfall at the observatory, ~5 km from the crater. Visual and seismic data showed no significant increases during the week prior to the explosion (table 1). On 1 June, two explosion earthquakes and two tremor earthquakes were recorded. The hazard status was set at Alert Level 2 (on a scale of 1-4).

Table 1. Seismicity and height of the gas plume at Lewotobi during 20 May-15 June 2003. Courtesy VSI.

Date Volcanic EQ Tectonic EQ Ash Emissions Tremor Plume Height(s)
20 May 2003 2 1 -- -- 25 m
21 May 2003 0 0 -- -- --
22 May 2003 4 1 -- -- 25 m
23 May 2003 9 5 -- -- 25 m
24 May 2003 6 3 -- -- 25 m
25 May 2003 5 1 -- -- 25 m
26 May 2003 0 0 -- -- 25 m
27 May 2003 2 6 -- -- 25 m
28 May 2003 0 2 -- -- --
29 May 2003 2 0 -- -- --
30 May 2003 6 3 -- -- 200 m
31 May 2003 6 0 -- -- --
01 Jun 2003 3 1 -- -- --
02-08 Jun 2003 13 12 29 20 300 m
09-15 Jun 2003 24 9 40 33 75 m

Activity during the week of 2-8 June 2003 was marked by explosions and ash emissions. Ash plumes reached a maximum height of 300 m above the summit. Seven explosions were recorded accompanied by a blasting sound on 3, 5, and 6 June. Ash fell at Bawalatang, Duang, and Boru villages. Shallow volcanic earthquakes were recorded, but were fewer in number compared to the previous week; there was no record of deep volcanic earthquakes, although tectonic earthquakes were recorded.

During the week of 9-15 June, activity was marked by ash emissions, with an ash plume reaching a maximum height of 75 m above the summit. Tremor events were also observed, with the tremor showing an amplitude of 0.5-7 mm. There were no deep volcanic earthquakes recorded, although the numbers of shallow volcanic earthquakes, tremor and ash emissions increased.

Information Contacts: Dali Ahmad, Volcanological Survey of Indonesia (VSI), Jalan Diponegoro No. 57, Bandung 40122, Indonesia (URL: http://www.vsi.esdm.go.id/).


October 2003 (BGVN 28:10) Citation IconCite this Report

Explosions and ashfall during June-July; seismicity stops in early September

Explosive ash eruptions from the summit crater of Lewotobi sent dark gray plumes 300-350 m high between 2 June and 13 July. Detonation sounds accompanied explosions on 3, 5, and 6 June. Ash fell in the villages of Bawalatang, Duang, and Boru in early June, and was reported at the volcano observatory post in early July. Ash explosions continued during 14-20 July with plumes rising 150 m above the summit. Poor weather conditions prevented observations in late July, although seismic records indicated continued activity; no reports were available for August. In early September an ash plume was reported to rise 25 m above the crater.

Seismicity during June and July was dominated by emissions events, but included tremor, explosion, and shallow volcanic earthquakes (table 2). Early September seismicity consisted of a high number of shallow volcanic events and some deep volcanic earthquakes, but all seismicity ceased after 3 September. Only four tectonic earthquakes were detected after this date, during 6-19 October. The 29 September-5 October report noted an ash plume rising to 25 m above the crater, but over the next two weeks the 25-m-high plume was described as gas emissions. The hazard status was downgraded to Alert Level 1 (on a scale of 1-4) the week of 13-19 October.

Table 2. Seismicity at Lewotobi, 2 June-19 October 2003. Note that no seismicity was recorded after 3 September 2003. Courtesy of VSI.

Date Deep Volcanic Shallow Volcanic Explosion Emission Tremor Tectonic
02 Jun-08 Jun 2003 0 13 7 29 20 12
09 Jun-15 Jun 2003 0 24 -- 40 33 9
30 Jun-06 Jul 2003 0 8 14 26 11 3
07 Jul-13 Jul 2003 0 16 10 52 4 1
14 Jul-20 Jul 2003 4 17 19 24 10 4
21 Jul-27 Jul 2003 1 10 5 25 5 4
28 Jul-03 Aug 2003 0 9 8 20 6 3
01 Sep-03 Sep 2003* 27 257 0 0 0 5

Information Contacts: Dali Ahmad, Hetty Triastuty, Nia Haerani, and Suswati, Volcanological Survey of Indonesia (VSI), Jalan Diponegoro No. 57, Bandung 40122, Indonesia (URL: http://www.vsi.esdm.go.id/).


January 2009 (BGVN 34:01) Citation IconCite this Report

Increase in seismicity during May 2008; more details on 2003 eruption

On 29 May 2008, the Center of Volcanology and Geological Hazard Mitigation (CVGHM) raised the Alert Level for the Flores Island volcano Lewotobi to 2 (on a scale of 1-4) due to an increase in seismicity during 12-29 May. White plumes typically rose about 25 m above the crater and drifted E; visual observations indicated no changes.

Explosive ash eruptions and high levels of seismicity occurred during May-September 2003 (BGVN28:06 and 28:10). Seismicity declined dramatically after an eruption on 31 August, and all volcanic earthquakes ceased after 3 September. The absence of reports during October 2003 until mid-May 2008 suggests Lewotobi apparently entered a protracted period of quiescence until May 2008. MODVOLC thermal surveillance of Lewotobi subsequent to the activity of October 2003 has not revealed any significant thermal activity to February 2009.

Additional details of 2003 eruption.According to an Agence France-Presse (AFP) news report, an eruption on 31 August 2003 took place at 1935. The article noted that hundreds of people from at least six villages fled E from their homes to the village of Konga. AFP said that volcanic material caused fires in forests within a 1-km radius of the crater and damaged crops on the flanks. On 1 September CVGHM reported to the Darwin Volcanic Ash Advisory Center (VAAC) that an ash plume rose ~2.5 km above the crater and drifted W, but the plume was not detected in imagery.

Following that 2003 eruption, according to the daily Jakarta Post, at least 565 villagers living on the slopes of Lewotobi were affected by sulfur and ash emissions. The residents experienced respiratory problems and skin afflictions. A 2008 Jakarta Post article indicated that an estimated 10,000 people live on the slopes of Lewotobi, most of them farming the fertile volcanic soil in the area.

Information Contacts: Center of Volcanology and Geological Hazard Mitigation (CVGHM), Jalan Diponegoro 57, Bandung 40122, Indonesia (URL: http://vsi.esdm.go.id/); Hawai'i Institute of Geophysics and Planetology (HIGP) 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/); 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/); Agence France-Presse (URL: http://www.afp.com/); Jakarta Post (URL: http://www.thejakartapost.com/).


April 2009 (BGVN 34:04) Citation IconCite this Report

Drops in steaming and seismicity during March 2009

Unrest caused authorities to elevate the alert level here to 2 in May 2008 (BGVN 34:01). No ash emissions were reported, as has been the case since 2003 (BGVN28:06, 28:10, 34:01).

On 23 March 2009, the Center for Volcanology and the Mitigation of Geologic Disaster (CVGHM) lowered the alert level on Lewotobi from 2 to 1 (on a scale of 1-4). This shift was based on visual observations and decreased seismicity during March. Rarely seen diffuse white plumes rose 25 m above the crater and drifted E. Visitors and residents continued to be advised not to approach the crater.

Over the period 1-23 March 2009 a cluster of shallow volcanic earthquakes occurred. Their initial numbers, 5-25 daily, soon declined to 1-5 occurrences per day. The total number of deep volcanic earthquakes did not change, averaging 1-3 daily. No tremor had been recorded since 1 February 2009 and at least as late as mid-2009.

Information Contacts: Center of Volcanology and Geological Hazard Mitigation (CVGHM), Jalan Diponegoro 57, Bandung 40122, Indonesia (URL: http://vsi.esdm.go.id/); Hawai'i Institute of Geophysics and Planetology (HIGP) 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/); 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/); Agence France-Presse (URL: http://www.afp.com/); Jakarta Post (URL: http://www.thejakartapost.com/).


December 2015 (BGVN 40:12) Citation IconCite this Report

Occasional increases in seismicity and white plumes during August 2011-October 2015

Lewotobi is composed of the Lewotobi Lakilaki (man) and Lewotobi Perempuan (woman) stratovolcanoes, with summit craters less than 2 km apart on Flores Island (figure 2). The last explosive eruption occurred in May 2003, accompanied by a high level of seismicity (BGVN 28:10). The volcano was apparently quiet through the middle of 2011, except for a brief period of unrest in May 2008 (BGVN 34:01) and March 2009 (BGVN 34:04). The report reviews activity through 7 October 2015, mostly from Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reports unless otherwise noted.

Figure (see Caption) Figure 2. Satellite image from 4 September 2013 showing Lewotobi volcano and associated features on eastern Flores Island: the two stratovolcanoes Lakilaki and Perempuan, and SE flank cone Iliwokar. The crater on the smaller Lakilaki edifice to the NW is 400 m wide, while Perempuan's is 700 m wide. Courtesy of Google Earth; data labels provided by GVP.

Seismicity increased during 26-31 August 2011, and plumes of "smoke" rose 15-50 m above the Perampuan crater rim. Based on the seismic data, the Alert Level for that crater was raised to 2 (Caution) (on a scale of 1-4) on 31 August. Increased seismicity and visual observations at Lakilaki after 17 September 2011 prompted PVMBG to raise the Alert Level to 2 for that cone as well on 22 September. Diffuse white plumes rose 15 m above the crater. At Alert Level 2 people are prohibited from going within a 1-km radius of the respective volcano.

Diffuse white plumes again rose 15-25 m above the summits of both craters during January-March 2012. Seismicity at both fluctuated, but had declined overall during September 2011-March 2012. The Alert Level at both was reduced from 2 to 1 (Normal) on 29 March 2012. Another period of increased seismicity on 28 September 2013 prompted PVMBG to again raise the Alert Level of Perempuan to 2.

Based on analysis of satellite images and wind data, the Darwin Volcanic Ash Advisory Centre (VAAC) reported that on 6 October 2014 a narrow, low-level ash plume from Lewotobi rose to an altitude of 3 km and drifted 185 km WNW. However, PVMBG did not report activity of any kind or raise the Alert Level. MODVOLC thermal alert pixels for that date showed a broad area on the E flank with 15 scattered anomalies extending to the shoreline, and three pixels the day before located just SE (figure 3). An alternate hypothesis is that fires spread NW due to prevailing winds, sending a low-level plume in that direction.

Figure (see Caption) Figure 3. MODVOLC maps showing thermal alert pixels at Lewotobi on 5 October (left) and 6 October (right) 2014. Courtesy of Hawai'i Institute of Geophysics and Planetology (HIGP), MODVOLC Thermal Alerts System.

White plumes were reported by PVMBG to be rising 15-20 m above Lakilaki during periods of clear weather from 1 February to 17 March 2015. Seismicity increased significantly on 13 March, especially the number of volcanic earthquakes and shallow volcanic earthquakes; harmonic tremor, tornillo events, and tectonic events were also detected. On 17 March the Alert Level was raised to 2. On 7 October 2015, PVMBG lowered the Alert Level to 1, based on visual observations and decreased seismicity over the previous three months.

Clear weather revealed white plumes rising 15 m above Perempuan during 17 July-25 August and 1 September-6 October 2015. Though the Alert Level had been raised on an unreported day, seismicity declined significantly after 1 August, and on 27 August, the Alert Level was lowered to 1.

Information Contacts: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM, Center for Volcanology and Geological Hazard Mitigation), Jl. Diponegoro 57, Bandung, West Java, Indonesia, 40 122 (URL: http://www.vsi.esdm.go.id/); 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/); 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/).

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 23 confirmed Holocene eruptive periods.

2023 Dec 23 - 2024 Jun 6 (continuing) Confirmed Eruption VEI: 2

Episode 1 | Eruption
2023 Dec 23 - 2024 Jun 6 (continuing) Evidence from Observations: Reported

List of 6 Events for Episode 1

Start Date End Date Event Type Event Remarks
2023 Dec 23    - - - - Ash Plume
2023 Dec 28    - - - - Fissure Upper SSE flank
2024 Jan 3    - - - - Fissure Upper NNW flank
2024 Jan 9    - - - - Lava flow Incandescent material was ejected from the summit and lava flows from the NNW-flank fissure descended the NW flank.
2024 Jan 10    - - - - VEI (Explosivity Index) VEI 2
2024 Jan 14    - - - - Pyroclastic flow

[ 2014 Oct 6 - 2014 Oct 6 ] Uncertain Eruption

Episode 1 | Eruption
2014 Oct 6 - 2014 Oct 6 Evidence from Observations: Reported

List of 2 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - VEI (Explosivity Index)
2014 Oct 6    - - - - Ash

2003 May 30 - 2003 Sep 1 (in or after) Confirmed Eruption VEI: 2

Episode 1 | Eruption Lewotobi Lakilaki
2003 May 30 - 2003 Sep 1 (in or after) Evidence from Observations: Reported

List of 6 Events for Episode 1 at Lewotobi Lakilaki

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
   - - - -    - - - - Property Damage
   - - - -    - - - - Evacuations
2003 May 30    - - - - VEI (Explosivity Index)
2003 Sep 1    - - - - VEI (Explosivity Index)

2002 Oct 12 - 2002 Oct 12 (?) Confirmed Eruption VEI: 1

Episode 1 | Eruption Lewotobi Lakilaki
2002 Oct 12 - 2002 Oct 12 (?) Evidence from Observations: Reported

List of 4 Events for Episode 1 at Lewotobi Lakilaki

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
   - - - -    - - - - Audible Sounds
2002 Oct 12    - - - - VEI (Explosivity Index)

1999 Mar 31 - 1999 Jul 1 (?) Confirmed Eruption VEI: 2

Episode 1 | Eruption Lewotobi Lakilaki
1999 Mar 31 - 1999 Jul 1 (?) Evidence from Observations: Reported

List of 7 Events for Episode 1 at Lewotobi Lakilaki

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
   - - - -    - - - - Ash Incandescent
   - - - -    - - - - Audible Sounds
   - - - -    - - - - Earthquakes (undefined)
1999 Mar 31    - - - - VEI (Explosivity Index)
1999 Jul 1    - - - - VEI (Explosivity Index)

1991 May 11 - 1992 Dec 31 (in or after) Confirmed Eruption VEI: 1

Episode 1 | Eruption Lewotobi Lakilaki
1991 May 11 - 1992 Dec 31 (in or after) Evidence from Observations: Reported

List of 9 Events for Episode 1 at Lewotobi Lakilaki

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Lava fountains
   - - - -    - - - - Ash
   - - - -    - - - - Lapilli
   - - - -    - - - - Bombs
   - - - -    - - - - Earthquakes (undefined) Before.
   - - - -    - - - - Earthquakes (undefined)
1991 May 11    - - - - VEI (Explosivity Index)
1991 Jul 19    - - - - Evacuations

1990 Jan 28 - 1990 Jun 16 ± 15 days Confirmed Eruption VEI: 1

Episode 1 | Eruption Lewotabi Lakilaki
1990 Jan 28 - 1990 Jun 16 ± 15 days Evidence from Observations: Reported

List of 5 Events for Episode 1 at Lewotabi Lakilaki

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash weak or small
   - - - -    - - - - Earthquakes (undefined) Before.
   - - - -    - - - - Earthquakes (undefined)
1990 Jan 28    - - - - VEI (Explosivity Index)

1971 Jan 16 ± 15 days Confirmed Eruption VEI: 2

Episode 1 | Eruption Lewotobi Lakilaki
1971 Jan 16 ± 15 days - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1 at Lewotobi Lakilaki

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
1971 Jan    - - - - VEI (Explosivity Index)

1970 Jul 2 ± 182 days Confirmed Eruption VEI: 2

Episode 1 | Eruption Lewotobi Lakilaki
1970 Jul 2 ± 182 days - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1 at Lewotobi Lakilaki

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
1970    - - - - VEI (Explosivity Index)

1968 Nov 28 - 1969 Feb 2 Confirmed Eruption VEI: 2

Episode 1 | Eruption Lewotobi Lakilaki
1968 Nov 28 - 1969 Feb 2 Evidence from Observations: Reported

List of 5 Events for Episode 1 at Lewotobi Lakilaki

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion weak or small
   - - - -    - - - - Ash
   - - - -    - - - - Lightning
   - - - -    - - - - Earthquakes (undefined)
1968 Nov 28    - - - - VEI (Explosivity Index)

1939 Dec 17 - 1940 Apr 21 Confirmed Eruption VEI: 2

Episode 1 | Eruption Lewotobi Lakilaki
1939 Dec 17 - 1940 Apr 21 Evidence from Observations: Reported

List of 3 Events for Episode 1 at Lewotobi Lakilaki

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
1939 Dec 17    - - - - VEI (Explosivity Index)

1935 Dec - 1935 Dec 25 (in or after) Confirmed Eruption VEI: 2

Episode 1 | Eruption Lewetobi Perempuan
1935 Dec - 1935 Dec 25 (in or after) Evidence from Observations: Reported

List of 4 Events for Episode 1 at Lewetobi Perempuan

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
   - - - -    - - - - Audible Sounds
1935 Dec    - - - - VEI (Explosivity Index)

1932 May 23 - 1933 Dec 26 ± 5 days Confirmed Eruption VEI: 3

Episode 1 | Eruption Lewotobi Lakilaki
1932 May 23 - 1933 Dec 26 ± 5 days Evidence from Observations: Reported

List of 9 Events for Episode 1 at Lewotobi Lakilaki

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Lava flow
   - - - -    - - - - Lava dome
   - - - -    - - - - Lava spine
   - - - -    - - - - Ash
   - - - -    - - - - Audible Sounds
   - - - -    - - - - Earthquakes (undefined) Before.
1932 May 23    - - - - VEI (Explosivity Index)

1921 Jan 1 - 1921 Dec 20 Confirmed Eruption VEI: 2

Episode 1 | Eruption Lewotobi Perempuan
1921 Jan 1 - 1921 Dec 20 Evidence from Observations: Reported

List of 5 Events for Episode 1 at Lewotobi Perempuan

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Lava dome
   - - - -    - - - - Ash
   - - - -    - - - - Blocks
1921 Jan 1    - - - - VEI (Explosivity Index)

1914 Jun 29 Confirmed Eruption VEI: 2

Episode 1 | Eruption Lewotobi Lakilaki
1914 Jun 29 - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1 at Lewotobi Lakilaki

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Lava flow
1914 Jun 29    - - - - VEI (Explosivity Index)

1909 Jan 8 - 1910 May 26 Confirmed Eruption VEI: 2

Episode 1 | Eruption Lewotobi Lakilaki
1909 Jan 8 - 1910 May 26 Evidence from Observations: Reported

List of 5 Events for Episode 1 at Lewotobi Lakilaki

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Lava flow
   - - - -    - - - - Ash
   - - - -    - - - - Earthquakes (undefined)
1909 Jan 8    - - - - VEI (Explosivity Index)

1907 Sep 28 - 1907 Oct 30 Confirmed Eruption VEI: 3

Episode 1 | Eruption Lewotobi Lakilaki
1907 Sep 28 - 1907 Oct 30 Evidence from Observations: Reported

List of 7 Events for Episode 1 at Lewotobi Lakilaki

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Lava flow
   - - - -    - - - - Lapilli
   - - - -    - - - - Bombs
   - - - -    - - - - Property Damage
1907 Sep 28    - - - - VEI (Explosivity Index)
1907 Oct 16
(?)
   - - - - Fatalities

1889 Confirmed Eruption VEI: 2

Episode 1 | Eruption Lewotobi Lakilaki
1889 - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1 at Lewotobi Lakilaki

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
1889    - - - - VEI (Explosivity Index)

1869 Jul 7 - 1869 Jul 27 Confirmed Eruption VEI: 2

Episode 1 | Eruption Lewotobi Lakilaki
1869 Jul 7 - 1869 Jul 27 Evidence from Observations: Reported

List of 4 Events for Episode 1 at Lewotobi Lakilaki

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Property Damage
1869 Jul 7    - - - - VEI (Explosivity Index)
1869 Jul 27    - - - - Fatalities

1868 Dec 15 Confirmed Eruption VEI: 2

Episode 1 | Eruption Lewotobi Lakilaki
1868 Dec 15 - Unknown Evidence from Observations: Reported

List of 2 Events for Episode 1 at Lewotobi Lakilaki

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
1868 Dec 15    - - - - VEI (Explosivity Index)

1868 Jul 13 (in or before) Confirmed Eruption VEI: 2

Episode 1 | Eruption Lewotobi Lakilaki
1868 Jul 13 (in or before) - Unknown Evidence from Observations: Reported

List of 4 Events for Episode 1 at Lewotobi Lakilaki

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
   - - - -    - - - - Blocks
1868 Jul 13
(in or before)
   - - - - VEI (Explosivity Index)

1865 May 4 Confirmed Eruption VEI: 2

Episode 1 | Eruption Lewotobi Lakilaki
1865 May 4 - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1 at Lewotobi Lakilaki

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
1865 May 4    - - - - VEI (Explosivity Index)

1861 May 4 - 1861 May 18 Confirmed Eruption VEI: 2

Episode 1 | Eruption Lewotobi Lakilaki
1861 May 4 - 1861 May 18 Evidence from Observations: Reported

List of 5 Events for Episode 1 at Lewotobi Lakilaki

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
   - - - -    - - - - Audible Sounds
   - - - -    - - - - Earthquakes (undefined)
1861 May 4    - - - - VEI (Explosivity Index)

[ 1859 Jul ] Uncertain Eruption

Episode 1 | Eruption Lewotobi Lakilaki
1859 Jul - Unknown Evidence from Unknown

List of 1 Events for Episode 1 at Lewotobi Lakilaki

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Volcanic "smoke"

1675 ± 25 years Confirmed Eruption VEI: 3

Episode 1 | Eruption Lewotobi Lakilaki
1675 ± 25 years - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1 at Lewotobi Lakilaki

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Lava flow
1675 ± 25 years    - - - - VEI (Explosivity Index)
Deformation History

There is no Deformation History data available for Lewotobi.

Emission History

There is no Emissions History data available for Lewotobi.

Photo Gallery

The summit of the sharp-peaked 1584-m Lewotobi Lakilaki is seen from its twin volcano located only 2 km to the SE, Lewotobi Perempuan. Lewotobi Lakilaki is the most active volcano on Flores Island, with frequent explosive eruptions in the 19th and 20th centuries. A 1932-33 eruption was accompanied by lava dome formation and pyroclastic flows.

Copyrighted photo by Katia and Maurice Krafft, 1971.
The Lewotobi "Husband and Wife" twin volcano is composed of the Lewotobi Lakilaki (seen in this view) and Lewotobi Perempuan stratovolcanoes, whose summits are less than 2 km apart on a NW-SE line. The summits of both volcanoes contain lava domes. Lewotobi Perempuan has had historical eruptions only in 1921 and 1935, whereas Lewotobi Lakilaki is one of the most active volcanoes on Flores Island, with frequent eruptions in the 19th and 20th centuries.

Copyrighted photo by Katia and Maurice Krafft, 1971.
A sulfur-encrusted, steaming lava dome in the summit crater of Lewotobi Perempuan volcano (seen here in 1971) was formed during an eruption from January 1 to December 1921. The only other historical eruption of Lewotobi Perampuan was in 1935, although its twin volcano to the SE, Lewotobi Lakilaki, is one of the most active volcanoes on Flores Island, with frequent eruptions in the 19th and 20th centuries.

Copyrighted photo by Katia and Maurice Krafft, 1971.
The summit crater of Lewotobi Perempuan, the SE of the two adjacent Lewotobi stratovolcanoes, contains a steaming lava dome that formed during an eruption in 1921. Solfataric activity has been observed here since the first report in 1821, although its only other eruption was in 1935.

Copyrighted photo by Katia and Maurice Krafft, 1971.
Lewotobi Lakilaki (left) and Lewotobi Perempuan (right) rise above a village on their western flanks. Both the conical Lakilaki and the broad Perempuan volcanoes have erupted during historical time.

Photo courtesy of Volcanological Survey of Indonesia, 1990.
The peaks of Gunung Lewotobi have differing profiles, seen here from the SW. The summit of sharp-peaked Lewotobi Lakilaki (left) lies only 2 km NW of the broader summit of Lewotobi Perempuan. Both volcanoes have erupted during historical time.

Photo published in Kemmerling 1929, "Vulkanen van Flores" (courtesy of Volcanological Survey of Indonesia).
The NE flanks of Gunung Lewotobi rise above the village of Nobo. Lewotobi Perempuan (left) is located SW of Lewotobi Lakilaki (right). Both of these volcanoes have erupted during historical time, although Lakilaki has erupted much more frequently.

Photo published in Kemmerling 1929, "Vulkanen van Flores" (courtesy of Volcanological Survey of Indonesia).
The first historical eruption of Lewotobi Perempuan took place in 1921, when explosive eruptions and lava dome growth were reported in January, May, and December. A gas-and-steam plume rises above the dome in this 1920's view from the NE. The 35-m-high lava dome was emplaced on the floor of crater B, the innermost of two craters at the summit.

Photo published in Kemmerling 1929, "Vulkanen van Flores" (courtesy of Volcanological Survey of Indonesia).
The lava dome emplaced in 1921 on the floor of the summit crater of Lewotobi Perempuan is seen from the NW crater rim in 1925. The 35-m-high dome was formed during the first of two historical eruptions. In contrast, Lewotobi Lakilaki, has erupted frequently since the 19th century.

Photo published in Kemmerling 1929, "Vulkanen van Flores" (courtesy of Volcanological Survey of Indonesia).
A plume rises above a lava dome emplaced in the summit crater of Lewotobi Perempuan volcano in 1921. The 90-130 m wide, 35-m-high lava dome is seen here from the NW crater rim.

Photo published in Kemmerling 1929, "Vulkanen van Flores" (courtesy of Volcanological Survey of Indonesia).
Lewotobi Lakilaki (left) and Lewotobi Perempuan (right) rise above forests on their western flanks. They were constructed along a NW-SE-trending line. Both volcanoes have erupted during historical time but Lakilaki has been more active.

Photo by Joël Boyer, 2004 (L.A.V.E.)
GVP Map Holdings

Maps are not currently available due to technical issues.

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.

Smithsonian Sample Collections Database

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

External Sites