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Iliwerung

Photo of this volcano
  • Country
  • Volcanic Region
  • Landform | Volc Type
  • Last Known Eruption
  • 8.532°S
  • 123.573°E

  • 583 m
    1,913 ft

  • 264250
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

Most Recent Weekly Report: 24 November-30 November 2021 Citation IconCite this Report

A submarine eruption at Iliwerung was observed during 28-29 November, prompting PVMBG to raise the Alert Level to 2 (on a scale of 0-4). Residents reported seeing the sea surface, 30 m from the shore to the S, bubbling up to heights of less than 1 m beginning at 2152 on 28 November; the activity lasted about an hour. Eruptive activity at the sea surface was again observed at 0517 on 29 November. An observer described bubbling water and a plume rising about 100 m a few hours later, at 0829, though they noted that the activity was about 1 km S of the Hobal submarine vent (about 3 km E of the summit), the site of multiple eruptions since 1973. PVMBG warned residents to stay away from the coastline and the water nearest to the activity.

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


Most Recent Bulletin Report: December 2021 (BGVN 46:12) Citation IconCite this Report

Submarine eruption during 28-29 November 2021

Iliwerung is constructed on the southern rim of the Lerek caldera on the south-facing peninsula on Lembata Island. The summit lava dome was formed during an eruption in 1870. Beginning in 1973-1974, submarine eruptions began from the lower ESE flank Hobal vent, located 2 km from the summit crater. Since then, activity originated from this vent during eruptions in 1983, 1993, 1999, and 2013. The eruption in August 2013 that consisted of diffuse fumarolic emissions, incandescence at sea level, discolored water, and shallow volcanic earthquakes (BGVN 40:05). This report updates activity through December 2021 and describes a submarine eruption during 28-29 November 2021. Information primarily comes from Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM, or the Center of Volcanology and Geological Hazard Mitigation).

A submarine eruption was observed during 28-29 November 2021, which prompted PVMBG to raise the Volcano Alert Level (VAL) to 2 (on a scale of 0-4). Residents reported that the ocean surface was bubbling up to heights of less than 1 m at 2152 on 28 November from a spot 30 m from the shore. This activity lasted about an hour and originated about 1 km SW of the Hobal submarine vent. Bubbling up was also observed at 0517 the next day on 29 November. Additional bubbling water and a plume was noted at 0829 that rose 100 m. Intermittent tremors were also detected, beginning on 29 November and continuing through the end of December.

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/).

Weekly Reports - Index


2021: November
2013: August
2001: October


24 November-30 November 2021 Citation IconCite this Report

A submarine eruption at Iliwerung was observed during 28-29 November, prompting PVMBG to raise the Alert Level to 2 (on a scale of 0-4). Residents reported seeing the sea surface, 30 m from the shore to the S, bubbling up to heights of less than 1 m beginning at 2152 on 28 November; the activity lasted about an hour. Eruptive activity at the sea surface was again observed at 0517 on 29 November. An observer described bubbling water and a plume rising about 100 m a few hours later, at 0829, though they noted that the activity was about 1 km S of the Hobal submarine vent (about 3 km E of the summit), the site of multiple eruptions since 1973. PVMBG warned residents to stay away from the coastline and the water nearest to the activity.

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


28 August-3 September 2013 Citation IconCite this Report

CVGHM reported that observers at a post 6 km away from Iliwerung reported that diffuse fumarolic emissions from the crater were visible during the mornings from 19 August to 1 September. Seismicity decreased on 19 August and remained at normal levels. On 2 September the Alert Level was lowered to 1 (on a scale of 0-4).

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


14 August-20 August 2013 Citation IconCite this Report

CVGHM reported that observers at a post 590 m a.s.l. and 6 km away from Iliwerung reported that diffuse fumarolic emissions from the crater were visible during the mornings from 1 to 19 August. Seismicity fluctuated during the month, but 81 shallow volcanic earthquakes were detected between 1606 and 1741 on 19 August, compared to a total of 30 the previous 18 days. The Alert Level was raised to 2 (on a scale of 0-4).

At 0714 on 20 August an eruption from the submarine SE flank vent, Hobal, ejected dense white plumes 2 km a.s.l. that drifted S. Incandescence at sea level was observed at 0746, and the water around the eruption site turned yellow. Fishermen and tourists were not permitted within a 2-km-radius of Hobal.

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


31 October-6 November 2001 Citation IconCite this Report

An increase in tectonic earthquakes around Iliwerung during 17-26 October led VSI to raise the Alert Level from 1 to 2 (on a scale of 1-4). From 2 to 11 earthquakes were felt per day with Modified Mercalli intensities of I-II. Visual and instrumental monitoring did not show a significant change in volcanic activity.

Source: 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.

08/1983 (SEAN 08:08) Submarine explosions

08/1993 (BGVN 18:08) Submarine eruption produces 100-m-high water columns

10/1993 (BGVN 18:10) Follow-up on Hobal vent eruption and 1979 tsunami

06/2003 (BGVN 28:06) Increase in felt earthquakes during October 2001

05/2015 (BGVN 40:05) Submarine flank eruption during August 2013 accompanied by crater fumarolic emissions

12/2021 (BGVN 46:12) Submarine eruption during 28-29 November 2021




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


August 1983 (SEAN 08:08) Citation IconCite this Report

Submarine explosions

Explosions occurred 17 and 18 August from a submarine vent (Hobal) S of Iliwerung. No casualties were reported.

Its previous eruption began with submarine activity in December 1973; by July 1974, there were two small islands at the eruption site and a third emerged in August. All have subsequently been eroded away. In July 1979, about 50 x 106 m3 of Iliwerung were removed by a landslide. About 1/3 of this material entered the sea, and (probably aided by additional submarine slumping) generated tsunami that killed hundreds of people.

Information Contacts: L. Pardyanto, VSI; AFP.


August 1993 (BGVN 18:08) Citation IconCite this Report

Submarine eruption produces 100-m-high water columns

A submarine eruption in the Alor Strait was reported on 16 September by a Japanese cargo ship. Crew members felt three shocks at around 0630, and observed a rising steam cloud or plume soon after. Explosions occurred at 0656 and 0855. Each explosion produced a water column ~100 m high, followed by a cone of upwelling water; no other unusual phenomena were observed after the explosions. From ~6.5 km away, the ship located the explosion site at about 8.538°S, 123.592°E, [2 km ESE of the Iliwerung summit]. The VSI confirmed that an eruption had occurred from the submarine Hobal vent at Iliwerung....

Information Contacts: JMA; M.A. Purvawinata, VSI.


October 1993 (BGVN 18:10) Citation IconCite this Report

Follow-up on Hobal vent eruption and 1979 tsunami

In September, Hobal vent on the [ESE] submarine flanks of Iliwerung volcano (figure 1) produced an eruption that broke the ocean surface (18:08).... During the eruption pyroclastic material sank within ~200 m of the point where it penetrated the ocean surface, consequently no samples were obtained. This suggests that the erupted material lacked sufficient closed vesicles to allow it to float.

Figure (see Caption) Figure 1. Map showing Iliwerung volcano, Hobal vent, and the known extent of the 1979 landslide that triggered a tsunami. Note that N is to the upper right. Courtesy of VSI.

Depth to the Hobal vent has never been measured, though in 1979 the VSI estimated it at 50 m. The bathymetry of this region is also significant because of its relevance to tsunamis. A 1979 landslide NW of Iliwerung reached the sea (figure 1), and probably aided by additional submarine slumping, triggered a tsunami that killed hundreds of people. Several areas evacuated prior to the 1979 landslide and tsunami still remain evacuated. Relevant aspects of the tectonic setting, and the effects of a 1992 earthquake-triggered tsunami on the N side of Flores Island are discussed by Yeh and others (1993).

Seismic data were acquired by VSI prior to the September Hobal eruption. The data were received at Lamaheku seismic station, at ~75-m elevation on the W flank of Iliwerung, 4.5 km from the Hobal vent. The seismic record is incomplete, but for July to September 1992, the number of volcanic B-type earthquakes averaged more than 70/month, reaching ~96 in September 1992. A gap in the record occurred in early 1993, but later in the year B-type earthquakes progressively increased from ~30 in May to 60 in September. Thus, the B-type events increased prior to the September eruption, but at least one interval with more B-type events passed without reports of concurrent eruptions.

VSI has informed local governments about the hazards of future eruptions, and has established a volcanic danger area that includes at least four communities on Iliwerung. Local VSI staff continue to monitor the region, and as of 1 November, were in the process of installing a new seismic station.

Reference. Yeh, H., Imamura, F., Synolakis, C., Yoshinobu T., Liu, P., and Shi, S., 1993, The Flores Island tsunamis: Eos, Transactions of the American Geophysical Union, v. 74, no. 33.

Information Contacts: W. Tjetjep, VSI.


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

Increase in felt earthquakes during October 2001

During 17-26 October 2001 the Volcanological Survey of Indonesia reported an increase in felt earthquakes. A total of 2-11 events occurred per day, with Mercalli magnitudes of I-II. The earthquakes S and P wave arrival times differed by between 1 and 35 seconds. Visual and instrumental monitoring revealed a lack of significant changes. The Alert Level was increased from 1 to 2 (on a scale of 1-4). No further reports were issued through at least May 2003.

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


May 2015 (BGVN 40:05) Citation IconCite this Report

Submarine flank eruption during August 2013 accompanied by crater fumarolic emissions

A submarine vent [~2 km ESE] of Iliwerung, named Hobal, erupted in December 1973-August 1974, August 1983 (SEAN 08:08), September 1993 (BGVN 28:06), and May-September 1999. No further activity was reported from this volcano until August 2013 when Hobal had another short eruption on the 20th.

The Center of Volcanology and Geological Hazard Mitigation (CVGHM) reported that observers at the observation post 6 km from Iliwerung saw diffuse fumarolic emissions from the crater during the mornings from 1 to 19 August 2013. The various seismic signals fluctuated during the month, but 81 shallow volcanic earthquakes were detected between 1606 and 1741 on 19 August. The Alert Level was raised to 2 (on a scale of 0-4).

At 0714 on 20 August 2013 an eruption from the submarine Hobal vent ejected dense white plumes to 2 km altitude that drifted S. Incandescence at sea level was observed at 0746, and the water around the eruption site turned yellow. Fishermen and tourists were not permitted within a 2 km radius of the activity.

Although seismicity had decreased on 19 August, the observers reported that the diffuse morning fumarolic crater emissions had continued through 1 September. On 2 September the Alert Level was lowered to 1 (on a scale of 0-4).

Information Contacts: Indonesian Center of Volcanology and Geological Hazard Mitigation, Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), Jalan Diponegoro 57, Bandung 40122, Indonesia (URL: http://www.vsi.esdm.go.id/).


December 2021 (BGVN 46:12) Citation IconCite this Report

Submarine eruption during 28-29 November 2021

Iliwerung is constructed on the southern rim of the Lerek caldera on the south-facing peninsula on Lembata Island. The summit lava dome was formed during an eruption in 1870. Beginning in 1973-1974, submarine eruptions began from the lower ESE flank Hobal vent, located 2 km from the summit crater. Since then, activity originated from this vent during eruptions in 1983, 1993, 1999, and 2013. The eruption in August 2013 that consisted of diffuse fumarolic emissions, incandescence at sea level, discolored water, and shallow volcanic earthquakes (BGVN 40:05). This report updates activity through December 2021 and describes a submarine eruption during 28-29 November 2021. Information primarily comes from Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM, or the Center of Volcanology and Geological Hazard Mitigation).

A submarine eruption was observed during 28-29 November 2021, which prompted PVMBG to raise the Volcano Alert Level (VAL) to 2 (on a scale of 0-4). Residents reported that the ocean surface was bubbling up to heights of less than 1 m at 2152 on 28 November from a spot 30 m from the shore. This activity lasted about an hour and originated about 1 km SW of the Hobal submarine vent. Bubbling up was also observed at 0517 the next day on 29 November. Additional bubbling water and a plume was noted at 0829 that rose 100 m. Intermittent tremors were also detected, beginning on 29 November and continuing through the end of December.

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/).

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 14 confirmed Holocene eruptive periods.

2021 Nov 28 - 2021 Nov 29 Confirmed Eruption VEI: 0

Episode 1 | Eruption
2021 Nov 28 - 2021 Nov 29 Evidence from Observations: Reported
 A submarine eruption was observed during 28-29 November. Residents reported seeing the sea surface, 30 m from the shore to the S, bubbling up to heights of less than 1 m. The activity was about 1 km S of the Hobal submarine vent (about 3 km E of the summit).

List of 2 Events for Episode 1

Start Date End Date Event Type Event Remarks
2021 Nov 28 2021 Nov 29 Observation Ocean bubbling and small plume (steam?).
2021 Nov 28    - - - - VEI (Explosivity Index) VEI 0

2013 Aug 20 - 2013 Aug 20 Confirmed Eruption VEI: 0

Episode 1 | Eruption Hobal (submarine vent on SE flank)
2013 Aug 20 - 2013 Aug 20 Evidence from Observations: Reported

List of 6 Events for Episode 1 at Hobal (submarine vent on SE flank)

Start Date End Date Event Type Event Remarks
2013 Aug 1 2013 Aug 19 Fumarolic or Solfataric CVGHM reported that observers at a post 6 km away reported that diffuse fumarolic emissions from the crater were visible during the mornings.
2013 Aug 19    - - - - Seismicity (volcanic) Seismicity fluctuated during the month, but 81 shallow volcanic earthquakes were detected between 1606 and 1741 on 19 August, compared to a total of 30 the previous 18 days.
2013 Aug 19 2013 Sep 1 Fumarolic or Solfataric CVGHM reported that observers at a post 6 km away from Iliwerung reported that diffuse fumarolic emissions from the crater were visible during the mornings.
2013 Aug 20    - - - - Eruption cloud At 0714 an eruption from the submarine SE flank vent, Hobal, ejected dense white plumes 2 km high that drifted S. Incandescence at sea level was observed at 0746, and the water around the eruption site turned yellow.
2013 Aug 20    - - - - Incandescence At 0714 an eruption from the submarine SE flank vent, Hobal, ejected dense white plumes 2 km high that drifted S. Incandescence at sea level was observed at 0746, and the water around the eruption site turned yellow.
2013 Aug 20    - - - - VEI (Explosivity Index) VEI 0

1999 May 22 - 1999 Sep 16 (in or after) ± 15 days Confirmed Eruption VEI: 0

Episode 1 | Eruption Hobal (submarine vent on SE flank)
1999 May 22 - 1999 Sep 16 (in or after) ± 15 days Evidence from Observations: Reported

List of 6 Events for Episode 1 at Hobal (submarine vent on SE flank)

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Seismicity (tremor) Before eruption.
   - - - -    - - - - Explosion
   - - - -    - - - - Audible Sounds
   - - - -    - - - - Earthquakes (undefined) Before.
   - - - -    - - - - Earthquakes (undefined)
1999 May 22    - - - - VEI (Explosivity Index)

1993 Sep 15 - 1993 Sep 19 Confirmed Eruption VEI: 2

Episode 1 | Eruption Hobal (submarine vent on SE flank)
1993 Sep 15 - 1993 Sep 19 Evidence from Observations: Reported

List of 6 Events for Episode 1 at Hobal (submarine vent on SE flank)

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
   - - - -    - - - - Bombs
   - - - -    - - - - Blocks
   - - - -    - - - - Earthquakes (undefined) Before.
1993 Sep 15    - - - - VEI (Explosivity Index)

1983 Aug 17 - 1983 Aug 18 Confirmed Eruption VEI: 1

Episode 1 | Eruption Hobal (submarine vent on SE flank)
1983 Aug 17 - 1983 Aug 18 Evidence from Observations: Reported

List of 4 Events for Episode 1 at Hobal (submarine vent on SE flank)

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Tsunami
1983 Aug 17    - - - - Fatalities
1983 Aug 17    - - - - VEI (Explosivity Index)

[ 1976 Mar 8 ] Uncertain Eruption

Episode 1 | Eruption Hobal (submarine vent on SE flank)
1976 Mar 8 - Unknown Evidence from Unknown

List of 3 Events for Episode 1 at Hobal (submarine vent on SE flank)

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Tsunami
1976 Mar 8    - - - - VEI (Explosivity Index)
1979 Jul 18    - - - - Fatalities

1973 Dec 5 - 1974 Aug 22 Confirmed Eruption VEI: 2

Episode 1 | Eruption Hobal (submarine vent on SE flank)
1973 Dec 5 - 1974 Aug 22 Evidence from Observations: Reported

List of 7 Events for Episode 1 at Hobal (submarine vent on SE flank)

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion weak or small
   - - - -    - - - - Earthquakes (undefined)
   - - - -    - - - - Island ephemeral
   - - - -    - - - - Tsunami
1973 Dec
(?)
   - - - - Fatalities
1973 Dec 5    - - - - VEI (Explosivity Index)
1974 Jul    - - - - VEI (Explosivity Index)

1952 Mar 24 Confirmed Eruption VEI: 1

Episode 1 | Eruption
1952 Mar 24 - Unknown Evidence from Observations: Reported

List of 4 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Avalanche
   - - - -    - - - - Ash
1952 Mar 24    - - - - VEI (Explosivity Index)

1951 Nov 12 - 1951 Nov 16 Confirmed Eruption VEI: 2

Episode 1 | Eruption
1951 Nov 12 - 1951 Nov 16 Evidence from Observations: Reported

List of 8 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Seismicity (volcanic)
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Ash
   - - - -    - - - - Lapilli
   - - - -    - - - - Audible Sounds
   - - - -    - - - - Lightning
   - - - -    - - - - Property Damage
1951 Nov 12    - - - - VEI (Explosivity Index)

1950 Sep 10 - 1950 Oct 2 Confirmed Eruption VEI: 2

Episode 1 | Eruption
1950 Sep 10 - 1950 Oct 2 Evidence from Observations: Reported

List of 12 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Seismicity (volcanic)
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Lava flow
   - - - -    - - - - Avalanche
   - - - -    - - - - Ash
   - - - -    - - - - Lapilli
   - - - -    - - - - Bombs
   - - - -    - - - - Audible Sounds
   - - - -    - - - - Lightning
   - - - -    - - - - Earthquakes (undefined) Before.
   - - - -    - - - - Property Damage
1950 Sep 10    - - - - VEI (Explosivity Index)

1949 Apr 9 - 1949 Apr 29 Confirmed Eruption VEI: 2

Episode 1 | Eruption
1949 Apr 9 - 1949 Apr 29 Evidence from Observations: Reported

List of 7 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Ash
   - - - -    - - - - Lapilli
   - - - -    - - - - Blocks
   - - - -    - - - - Lightning
1949 Apr 9    - - - - VEI (Explosivity Index)

1948 Apr 7 - 1948 Nov 26 Confirmed Eruption VEI: 2

Episode 1 | Eruption East flank (Iligripe)
1948 Apr 7 - 1948 Nov 26 Evidence from Observations: Reported

List of 10 Events for Episode 1 at East flank (Iligripe)

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Seismicity (volcanic) Before eruption.
   - - - -    - - - - Seismicity (volcanic)
   - - - -    - - - - Explosion
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Lava dome
   - - - -    - - - - Audible Sounds
   - - - -    - - - - Earthquakes (undefined)
   - - - -    - - - - Property Damage
1948 Apr 7    - - - - Fatalities
1948 Apr 7    - - - - VEI (Explosivity Index)

[ 1941 Jun 5 ] Uncertain Eruption

Episode 1 | Eruption
1941 Jun 5 - Unknown Evidence from Unknown

List of 1 Events for Episode 1

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

1928 Confirmed Eruption VEI: 2

Episode 1 | Eruption Iliwerung
1928 - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1 at Iliwerung

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Lava dome
1928    - - - - VEI (Explosivity Index)

1910 Confirmed Eruption VEI: 2

Episode 1 | Eruption Iliwerung
1910 - Unknown Evidence from Observations: Reported

List of 2 Events for Episode 1 at Iliwerung

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion Uncertain
1910    - - - - VEI (Explosivity Index)

1870 Confirmed Eruption VEI: 3

Episode 1 | Eruption Iliwerung (Iliadowajo)
1870 - Unknown Evidence from Observations: Reported

List of 4 Events for Episode 1 at Iliwerung (Iliadowajo)

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Lava dome
1870    - - - - Fatalities
1870    - - - - VEI (Explosivity Index)
Deformation History

There is no Deformation History data available for Iliwerung.

Emission History

There is no Emissions History data available for Iliwerung.

Photo Gallery

A landslide in 1979, not associated with an eruption, originated from the northern end of the Iliwerung volcanic massif. The resulting debris avalanche swept into the Indian Ocean at a high velocity and produced a tsunami that scoured the shoreline of Lembata (Lomblen) Island, killing more than 500 people. The extent of the runup of the tsunami can be seen forming the flat barren area in the center of the photo, which was taken from the SW on 27 July 1979, shortly after the tsunami.

Photo by Ruska Hadian, 1979 (Volcanological Survey of Indonesia).
The Watuwawer fumarole field at Iliwerung volcano provides a permanent heat source for cooking utilized by people living on the flanks of the volcano.

Photo by Ruska Hadian, 1979 (Volcanological Survey of Indonesia).
A lava dome, formed during the first historical eruption of Iliwerung volcano in 1870, occupies the summit crater of the volcano, seen here in 1979 from the western rim of Ado Wajung crater. Iliwerung forms one of the south-facing peninsulas on Lembata (Lomblen) Island, and has a series of lava domes and craters along N-S and NW-SE lines. Many of these vents, including submarine vents offshore, have erupted in historical time.

Photo by Ruska Hadian, 1979 (Volcanological Survey of Indonesia).
A composite photo taken in 1979 shows the crater at summit of Iliwerung lava dome. The summit lava dome was formed during an eruption in 1870, the first historical eruption of Iliwerung volcano.

Photo by Ruska Hadian, 1979 (Volcanological Survey of Indonesia).
Iligripe lava dome on the SE flank of Iliwerung volcano on Lembata (formerly Lomblen) Island formed during an eruption from April 7 to November 26, 1948. Growth of the 190-m-high lava dome, seen here at the center of this 1979 photo, was accompanied by explosive eruptions and pyroclastic flows.

Photo by Ruska Hadian, 1979 (Volcanological Survey of Indonesia).
A lava dome, formed during the first historical eruption of Iliwerung volcano in 1870, occupies the summit crater of the volcano, seen here in 1979 from the rim of Ado Wajung crater. Iliwerung forms one of the south-facing peninsulas on Lembata (formerly Lomblen) Island, and has a series of lava domes and craters along N-S and NW-SE lines. Many of these vents, including submarine vents offshore, have erupted in historical time.

Photo by Volcanological Survey of Indonesia.
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/).
Iliwerung forms a peninsula in southern Lembata island, seen here in this July 2019 Planet Labs satellite image monthly mosaic (N is at the top; this image is approximately 11 km across). The 330 x 400 m recent crater is near the eastern coastline in this view and submarine eruptions have produced ephemeral islands off the SE flank.

Satellite image courtesy of Planet Labs Inc., 2019 (https://www.planet.com/).
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 Iliwerung in the Smithsonian's NMNH Department of Mineral Sciences Rock and Ore collection.

External Sites