Logo link to homepage

Ruang

Photo of this volcano
  • Country
  • Primary Volcano Type
  • Last Known Eruption
  •  
  • 2.3°N
  • 125.37°E

  • 725 m
    2379 ft

  • 267010
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number
Most Recent Weekly Report: 22 June-28 June 2022 Citation IconCite this Report

An increased number of deep volcanic earthquakes at Ruang in April prompted PVMBG to raise the Alert Level to 2 (on a scale of 1-4). A total of 232 deep volcanic earthquakes were recorded by the seismic network during 1 April-22 June, with just over half of them occurring in early to mid-April. No data was recorded from 18 April through 11 May due to technical difficulties. The network recorded 6-20 events during 11-31 May and just 1-2 events during 1-21 June. PVMBG lowered the Alert Level to 1 on 23 June.

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


Most Recent Bulletin Report: February 2004 (BGVN 29:02) Citation IconCite this Report

Eruption on 25 September 2002 is the largest in Indonesia in many years

The 25 September 2002 eruption of Ruang (BGVN 27:10 and 28:08) was, according to the Darwin Volcanic Ash Advisory Center (VAAC), the largest in Indonesia for many years and was well observed by satellite sensors. The eruption cloud reached a height of ~ 20 km, and a pyroclastic flow toward the SE damaged an area 1.6 km². Although no village was hit by the pyroclastic flow, two were heavily damaged by very thick ash material.

The Darwin VAAC and Bureau of Meteorology have published images and animations of the eruption clouds (figure 2). The satellites and images included those from Aqua/MODIS, GMS Java Animation, and AVHRR sensors. Some ash clouds dispersed towards Singapore and Jakarta. A higher level cloud remained nearly stationary near the tropopause (the top of the troposphere, where most of the Earth's weather occurs). The highest cloud moved eastwards in the stratosphere. The color/shading reflects the strength of the detected ash signal.

Figure (see Caption) Figure 2. Night-time infrared image of the Ruang eruption processed to highlight volcanic ash. N is towards the top; the local island margins are shown, Sulawesi to the right and Borneo to the left. The enhanced areas disclose the W portion of the plume drifting over Borneo and the higher E ash and gas cloud nearly stationary over the eruption site. A third area of ash and ice cloud is nearly invisible near the bottom center. Courtesy of NASA, NOAA, and the Darwin VAAC.

The TOMS scientists published an image on their website (figure 3), described as follows: "The TOMS overpass on September 25 was too early to capture the fresh eruption cloud, but ash and SO2 were evident on the following day. The aerosol signal over S Borneo is at least partly due to smoke from biomass burning; the ash cloud from Ruang can be seen over NE Borneo. A data gap may be obscuring any SO2 or ash immediately W of Ruang."

Figure (see Caption) Figure 3. Ruang erupted on 25 September 2002. A pass the next day of the Earth Probe satellite with the Total Ozone Mapping Spectrometer (TOMS) instrument yielded this map of SO2 concentrations. Courtesy of Simon Carn and Arlin Krueger.

Information Contacts: Darwin Volcanic Ash Advisory Center (VAAC), Commonwealth Bureau of Meteorology, Northern Territory Regional Office, PO Box 40050, Casuarina, NT 0811, Australia (URL: http://www.bom.gov.au/info/vaac/); Nia Haerani, Directorate of Volcanology and Geological Hazards (formerly VSI), Jalan Diponegoro No 57, Bandung 40122, Indonesia (URL: http://www.vsi.esdm.go.id/); Simon A. Carn and Arlin Krueger, Joint Center for Earth Systems Technology (NASA/UMBC), University of Maryland, Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA (URL: https://so2.gsfc.nasa.gov/).

Weekly Reports - Index


2022: April | June
2015: March | June
2002: September | October


22 June-28 June 2022 Citation IconCite this Report

An increased number of deep volcanic earthquakes at Ruang in April prompted PVMBG to raise the Alert Level to 2 (on a scale of 1-4). A total of 232 deep volcanic earthquakes were recorded by the seismic network during 1 April-22 June, with just over half of them occurring in early to mid-April. No data was recorded from 18 April through 11 May due to technical difficulties. The network recorded 6-20 events during 11-31 May and just 1-2 events during 1-21 June. PVMBG lowered the Alert Level to 1 on 23 June.

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


13 April-19 April 2022 Citation IconCite this Report

PVMBG reported that at least 121 deep volcanic earthquakes at Ruang were recorded during 1-16 April, though the number of those events began to increase on 7 April. No visible changes to the crater were noted, but weather conditions sometimes prevented views. Seismicity significantly changed on 16 April, characterized by 50 deep volcanic earthquakes, two local tectonic earthquakes, and four felt earthquakes. That same day the Alert Level was raised to 2 (on a scale of 1-4) and residents and tourists were warned to stay 1.5 km away from the active craters and 2.5 km on the E, SE, S, and SW flanks. Elevated seismicity continued to be recorded through 18 April.

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


3 June-9 June 2015 Citation IconCite this Report

PVMBG reported that seismicity at Ruang decreased from 14 March through 2 June. Emissions were unobserved during periods of clear weather from 1 May through 2 June. The Alert Level was lowered to 1 (on a scale of 1-4) on 3 June. Residents and tourists were warned not to approach the active craters.

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


11 March-17 March 2015 Citation IconCite this Report

PVMBG reported that emissions from Ruang were unobserved during periods of clear weather from 1 January through 12 March. Seismicity increased starting on 6 March prompting PVMBG to raise the Alert Level to 2 (on a scale of 1-4) on 12 March. Residents and tourists were warned not to approach the craters within a 1.5-km radius.

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


30 October-5 November 2002 Citation IconCite this Report

During 21-27 October, a thick low-level ash plume infrequently rose above Ruang. Rainfall on 23 October caused lahars to flow down the volcano's flanks during 1445-1545. Ruang remained at Alert Level 2 (on a scale of 1-4).

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


25 September-1 October 2002 Citation IconCite this Report

VSI reported that following the 25 September Ruang eruption there was no significant volcanic activity; only thin white clouds rose 100 m above the summit. On 30 September VSI decreased the Alert Level at Ruang from 4 to 3 (on a scale of 1-4).

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


18 September-24 September 2002 Citation IconCite this Report

VSI increased the Alert Level at Ruang to 4 (the highest level) when the volcano began to erupt on 25 September at 0100. During the 7-hour eruption an ash cloud rose 0.5-1 km above the summit. Ruang erupted again at 1140, producing an ash cloud that VSI reported rose to 5 km above the summit. According to the Darwin VAAC, satellite imagery revealed that an ash cloud reached ~16 km above the volcano. People living near the volcano at desa Pumpente and desa Laimpatehi were evacuated.

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


Bulletin Reports - Index

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

08/1996 (BGVN 21:08) Plume observed in late June

10/2002 (BGVN 27:10) Eruption on 25 September 2002 sends ash to at least 5 km

08/2003 (BGVN 28:08) Rapid decrease in activity following September 2002 eruption

02/2004 (BGVN 29:02) Eruption on 25 September 2002 is the largest in Indonesia in many years




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


August 1996 (BGVN 21:08) Citation IconCite this Report

Plume observed in late June

Pilots from Qantas Airlines reported an eruption around 1600 on 27 June. A plume moved W and reached an altitude of about 6,000 m. However, the eruption was not visible in GMS satellite imagery.

Information Contacts: Bureau of Meteorology, Northern Territory Regional Office, P.O. Box 735, Darwin, NT 0801 Australia; NOAA/NESDIS Satellite Analysis Branch, Room 401, 5200 Auth Road, Camp Springs, MD 20746, USA.


October 2002 (BGVN 27:10) Citation IconCite this Report

Eruption on 25 September 2002 sends ash to at least 5 km

The last reported activity at Ruang occurred when Qantas Airlines pilots observed an eruption around 1600 on 27 June 1996 (BGVN 21:08). A resulting plume moved W and reached an altitude of ~6 km. However, the eruption was not visible in GMS satellite imagery. The last known confirmed eruption at Ruang occurred in 1949.

A drastic increase of seismic events - from 3 to 24 events/day - was observed on 24 September by the Volcanological Survey of Indonesia (VSI). The next day, people near the volcano reported hearing a noise, and ash eruptions began by 0100. By 0300 ash emissions were continuous, and ash began falling around Ruang island and the nearby island of Tagulandang. Observers reported that the sounds accompanying the eruption were weak. By 0400 more than 1,000 people living near the volcano were evacuated to a nearby island. Around 0800, the Alert Level advanced to the highest status (level 4).

The first strong eruption commenced at 1140 on 25 September, producing thick black clouds that rose 3 km. Ten minutes later, a second eruption sent ash clouds rising 5 km. At 1210 the activity subsided enough to observe glowing material on E flank. The specific eruption site has not been firmly established. It has been presumed by VSI that it originated from "Crater II" or "where the 1949 lava originated (E side of summit)." The eruption column was reported from ground-based observations as rising to at least 5 km, and by Darwin VAAC advisories as rising to about 17 km. According to the Darwin VAAC, satellite imagery revealed that the ash cloud drifted westward to Borneo and Sumatra. Satellite images from NOAA showed the plume drifting SW with other components drifting W (figure 1). By 30 September the volcano was quiet with only a thin white plume rising about 100 m. The Alert Level was reduced from 4 to 3 on 30 September 2002.

Figure (see Caption) Figure 1. Satellite imagery on 25 September 2002 showed a large eruption plume from Ruang. The volcano's location is shown by the arrow. The plume appears to branch into SW- and W-drifting components. Courtesy NOAA.

Information Contacts: Volcanological Survey of Indonesia (VSI), Jalan Diponegoro No. 57, Bandung 40122, Indonesia (URL: http://www.vsi.esdm.go.id/); Darwin Volcanic Ash Advisory Center (VAAC), Bureau of Meteorology, Northern Territory Regional Office, P.O. Box 735, Darwin, NT 0801 Australia; NOAA/NESDIS Satellite Analysis Branch, Room 401, 5200 Auth Road, Camp Springs, MD 20746, USA.


August 2003 (BGVN 28:08) Citation IconCite this Report

Rapid decrease in activity following September 2002 eruption

Volcanic activity had decreased by 30 September 2002 after a strong eruption on the 25th. After the hazard status was lowered from Alert Level 4 to 3 on 30 September, it was dropped to Level 2 during the week of 7-13 October. However, activity continued to be higher than normal that week, with frequent strong emissions and "thick white ash" rising ~100 m above the summit. Emission earthquakes decreased (table 1). High-pressure plumes decreased in frequency from 14 October through 10 November, but "thick white ash" continued to rise from the summit. No ashfall was reported during October or November. Rainfall on 23 October caused a lahar. No volcanic or emission earthquakes were recorded during 4-10 November, and the Alert Level was reduced to level 1.

Table 1. Seismicity at Ruang, 7 October-10 November 2002. Courtesy of VSI.

Date Emission earthquakes Tectonic earthquakes
07 Oct-13 Oct 2002 3 46
14 Oct-20 Oct 2002 6 39
21 Oct-27 Oct 2002 2 85
28 Oct-03 Nov 2002 2 63
04 Nov-10 Nov 2002 -- 58

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


February 2004 (BGVN 29:02) Citation IconCite this Report

Eruption on 25 September 2002 is the largest in Indonesia in many years

The 25 September 2002 eruption of Ruang (BGVN 27:10 and 28:08) was, according to the Darwin Volcanic Ash Advisory Center (VAAC), the largest in Indonesia for many years and was well observed by satellite sensors. The eruption cloud reached a height of ~ 20 km, and a pyroclastic flow toward the SE damaged an area 1.6 km². Although no village was hit by the pyroclastic flow, two were heavily damaged by very thick ash material.

The Darwin VAAC and Bureau of Meteorology have published images and animations of the eruption clouds (figure 2). The satellites and images included those from Aqua/MODIS, GMS Java Animation, and AVHRR sensors. Some ash clouds dispersed towards Singapore and Jakarta. A higher level cloud remained nearly stationary near the tropopause (the top of the troposphere, where most of the Earth's weather occurs). The highest cloud moved eastwards in the stratosphere. The color/shading reflects the strength of the detected ash signal.

Figure (see Caption) Figure 2. Night-time infrared image of the Ruang eruption processed to highlight volcanic ash. N is towards the top; the local island margins are shown, Sulawesi to the right and Borneo to the left. The enhanced areas disclose the W portion of the plume drifting over Borneo and the higher E ash and gas cloud nearly stationary over the eruption site. A third area of ash and ice cloud is nearly invisible near the bottom center. Courtesy of NASA, NOAA, and the Darwin VAAC.

The TOMS scientists published an image on their website (figure 3), described as follows: "The TOMS overpass on September 25 was too early to capture the fresh eruption cloud, but ash and SO2 were evident on the following day. The aerosol signal over S Borneo is at least partly due to smoke from biomass burning; the ash cloud from Ruang can be seen over NE Borneo. A data gap may be obscuring any SO2 or ash immediately W of Ruang."

Figure (see Caption) Figure 3. Ruang erupted on 25 September 2002. A pass the next day of the Earth Probe satellite with the Total Ozone Mapping Spectrometer (TOMS) instrument yielded this map of SO2 concentrations. Courtesy of Simon Carn and Arlin Krueger.

Information Contacts: Darwin Volcanic Ash Advisory Center (VAAC), Commonwealth Bureau of Meteorology, Northern Territory Regional Office, PO Box 40050, Casuarina, NT 0811, Australia (URL: http://www.bom.gov.au/info/vaac/); Nia Haerani, Directorate of Volcanology and Geological Hazards (formerly VSI), Jalan Diponegoro No 57, Bandung 40122, Indonesia (URL: http://www.vsi.esdm.go.id/); Simon A. Carn and Arlin Krueger, Joint Center for Earth Systems Technology (NASA/UMBC), University of Maryland, Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA (URL: https://so2.gsfc.nasa.gov/).

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

Eruptive History

There is data available for 12 confirmed Holocene eruptive periods.

2002 Sep 25 - 2002 Sep 29 (?) Confirmed Eruption Max VEI: 4 (?)

Episode 1 | Eruption Episode
2002 Sep 25 - 2002 Sep 29 (?) Evidence from Observations: Reported

List of 7 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Ash
   - - - -    - - - - Lahar or Mudflow
   - - - -    - - - - Property Damage
   - - - -    - - - - Evacuations
2002 Sep 25    - - - - VEI (Explosivity Index)

[ 1996 Jun 27 ] Uncertain Eruption

Episode 1 | Eruption Episode
1996 Jun 27 - Unknown Evidence from Unknown

List of 1 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion Uncertain

1949 Jan 5 - 1949 Jan 19 (in or after) Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode
1949 Jan 5 - 1949 Jan 19 (in or after) Evidence from Observations: Reported

List of 5 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Lava flow
   - - - -    - - - - Lava flow Entered water.
   - - - -    - - - - Lava dome
1949 Jan 5    - - - - VEI (Explosivity Index)

[ 1946 Oct 13 - 1946 Oct 15 ] Discredited Eruption

CAVW lists an explosive eruption during 13-15 October 1946, but Neuman Van Padang (1959), eight years after his CAVW compilation ,states there was no eruption between Petroeschevsky's observation of 480 degree solfataras in September 1946 and the January 1949 eruption.

[ 1940 Apr ] Discredited Eruption

Increased fumarolic activity only in 1940 and 1941 (Neumann van Padang, 1959).

[ 1918 Feb ] Discredited Eruption

Increased fumarolic activity only in 1918 (Neumann van Padang, 1959).

1914 May 29 - 1915 Feb 28 ± 30 days Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Summit craters K2 and K3
1914 May 29 - 1915 Feb 28 ± 30 days Evidence from Observations: Reported
 Explosive eruption with nuees ardentes destroyed 1904 lava dome. Eruption continued, with interruptions, until first months of 1915. Summit craters K2 and K3 formed in this eruption (Neumann Van Padang 1959).

List of 5 Events for Episode 1 at Summit craters K2 and K3

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

1904 Apr 22 - 1905 May 27 Confirmed Eruption Max VEI: 3 (?)

Episode 1 | Eruption Episode
1904 Apr 22 - 1905 May 27 Evidence from Observations: Reported

List of 8 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Lava flow
   - - - -    - - - - Lava flow Entered water.
   - - - -    - - - - Lava dome
   - - - -    - - - - Lahar or Mudflow
   - - - -    - - - - Property Damage
1904 Apr 22    - - - - VEI (Explosivity Index)

1889 Jun Confirmed Eruption Max VEI: 1

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

List of 2 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Lava dome
1889 Jun    - - - - VEI (Explosivity Index)

1874 Nov 15 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode
1874 Nov 15 - Unknown Evidence from Observations: Reported

List of 4 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Property Damage
1874 Nov 15    - - - - VEI (Explosivity Index)

1871 Mar 2 - 1871 Mar 14 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode
1871 Mar 2 - 1871 Mar 14 Evidence from Observations: Reported

List of 8 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Earthquakes (undefined) Before.
   - - - -    - - - - Earthquakes (undefined)
   - - - -    - - - - Tsunami
   - - - -    - - - - Property Damage
1871 Mar 2    - - - - VEI (Explosivity Index)
1871 Mar 3    - - - - Fatalities

1870 Aug 27 - 1870 Aug 28 Confirmed Eruption Max VEI: 3 (?)

Episode 1 | Eruption Episode
1870 Aug 27 - 1870 Aug 28 Evidence from Observations: Reported

List of 5 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Property Damage
   - - - -    - - - - Evacuations
1870 Aug 27    - - - - Fatalities
1870 Aug 27    - - - - VEI (Explosivity Index)

1856 Sep Confirmed Eruption Max VEI: 1

Episode 1 | Eruption Episode
1856 Sep - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Lava dome
1856 Sep    - - - - VEI (Explosivity Index)

1840 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode
1840 - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Pyroclastic flow
1840    - - - - VEI (Explosivity Index)

1836 Apr 22 (?) - 1836 Apr 24 (?) Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode
1836 Apr 22 (?) - 1836 Apr 24 (?) Evidence from Observations: Reported

List of 2 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
1836 Apr 22
(?)
   - - - - VEI (Explosivity Index)

1808 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode
1808 - Unknown Evidence from Observations: Reported
 An eruption (no details) was reported in 1810 (Petroeschevsky and Klompe, 1951), but CAVW states that the 1810 and 1811 eruption reports seem to relate to an eruption in 1808. Neumann van Padang (1959) lists no 1810 event.

List of 4 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Property Damage
1808    - - - - VEI (Explosivity Index) VEI 2
Deformation History

There is no Deformation History data available for Ruang.

Emission History

There is data available for 1 emission periods. Expand each entry for additional details.


Emissions during 2002 Sep 26 - 2002 Sep 26 [80 kt SO2 at 22 km altitude]

Start Date: 2002 Sep 26 Stop Date: 2002 Sep 26 Method: Satellite (Earth Probe TOMS)
SO2 Altitude Min: 22 km SO2 Altitude Max: 22 km Total SO2 Mass: 80 kt

Data Details

Date Start Date End Assumed SO2 Altitude SO2 Algorithm SO2 Mass
20020926 22.0 80.000
GVP Map Holdings

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

Smithsonian Sample Collections Database

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

External Sites