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Ruang

Photo of this volcano
  • Indonesia
  • Sangihe Volcanic Arc
  • Composite | Stratovolcano
  • 2024 CE
  • Country
  • Volcanic Province
  • Landform | Volc Type
  • Last Known Eruption
  • 2.3°N
  • 125.37°E

  • 725 m
    2,379 ft

  • 267010
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

Most Recent Weekly Report: 15 May-21 May 2024 Citation IconCite this Report

On 15 May BNPB reported that a total of 9,343 residents of Tagulandang and Ruang islands remained in evacuation centers because of eruptions from Ruang. According to PVMBG daily white steam-and-gas plumes that were sometimes dense rose as high as 700 m above the summit and drifted in multiple directions during 15-21 May. The Alert Level was lowered to 2 (the second lowest level on a scale of 1-4) at 0900 on 18 May and the public was warned to stay 2 km away from the active crater.

Sources: Badan Nacional Penanggulangan Bencana (BNPB), 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


2024: April | May
2022: April | June
2015: March | June
2002: September | October


15 May-21 May 2024 Citation IconCite this Report

On 15 May BNPB reported that a total of 9,343 residents of Tagulandang and Ruang islands remained in evacuation centers because of eruptions from Ruang. According to PVMBG daily white steam-and-gas plumes that were sometimes dense rose as high as 700 m above the summit and drifted in multiple directions during 15-21 May. The Alert Level was lowered to 2 (the second lowest level on a scale of 1-4) at 0900 on 18 May and the public was warned to stay 2 km away from the active crater.

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


8 May-14 May 2024 Citation IconCite this Report

PVMBG reported that during 1-12 May seismicity at Ruang was characterized by decreasing numbers of volcanic earthquakes and continuous tremor with decreasing amplitudes. During 8-13 May white plumes rose 200-400 m above the summit and drifted in multiple directions. The Alert Level was lowered to 3 (the second highest level on a scale of 1-4) and the public was warned to stay 4 km away from the active crater.

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


1 May-7 May 2024 Citation IconCite this Report

PVMBG reported that seismicity at Ruang during 1-2 May was characterized by continuous tremors along with both deep and shallow volcanic earthquakes. The number of seismic events was decreasing based on a seismic station at the Ruang Post, 5 km from the crater; two closer stations, 1.5 and 2.7 km from the crater, had been damaged by eruptions. During 1-4 and 7 May white-and-gray ash plumes that were sometimes dense rose 100-700 m above the summit and drifted in multiple directions. Dense white steam-and-gas plumes rose 100-450 m above the summit and drifted NE, E, and S during 5-7 May.

On 5 May PVMBG reduced the exclusion zone from a 7 km radius around the active crater to 5 km. According to news reports a total of 5,849 residents of Tagulandang Island had been evacuated by 5 May; additional evacuations were halted after the exclusion zone was changed. The Sam Ratulangi International Airport (98 km SW in Manado, North Sulawesi) reopened on 5 May, though several airports remained closed including Djalaludin Airport in Gorongtalo, Siau Airport in the Sitaro Islands, Naha Airport in the Sangihe Islands, Lolakndi Bolaang Mongondow Airport, Miangas Airport, and Melonguane Airport in the Talaud Islands. The Alert Level remained at 4 (the highest level on a scale of 1-4).

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


24 April-30 April 2024 Citation IconCite this Report

PVMBG reported that seismicity significantly increased at Ruang on 29 April and the signals indicated magma moving towards the surface. Earthquakes began to be felt at 0015 on 30 April. At 0115 the earthquakes intensified; residents in neighboring Tagulandang Island reportedly felt continuous shaking, heard loud roaring, and saw an ash plume rising about 2 km above the summit. Activity continued to escalate and at 0130 the Alert Level was raised to 4 (the highest level on a scale of 1-4). The public was warned to stay 7 km away from the active crater and residents on Tagulandang within 6 km were instructed to evacuate. A webcam photo from 0232 on 30 April showed lava being ejected above the summit; an eruptive event was recorded in seismic data at 0235. According to the Darwin VAAC ash plumes had risen to 15.2 km (50,000 ft) a.s.l. by 0300 and to 19.2 km (63,000 ft) a.s.l. by 0320, and by 0620 were expanding radially; the plumes may have risen to 23 km (75,400 ft) a.s.l. or more based on other expert analysis.

PVMBG noted that at 0835 dense gray-to-black ash plumes rose at least 5 km and drifted E and S. A webcam photo from 0827 showed multiple pyroclastic density currents descending the flanks. According to a characterization by BNPB the eruption ejected incandescent lava high above the summit and lightning was frequently seen in the plumes. Tephra fell over a more extensive area compared the 16-18 April eruption phase; gravel-sized tephra fell in Apengsala, about 8 km NNE from Ruang’s central vent, and outside of the exclusion zone. According to a news report residents felt shock waves from the explosions. At least three eruptive events were recorded during 1200-1800 that produced gray-and-black ash plumes at least as high as 1.5 km. The VAAC noted that by 1510 the high-level plume had detached from the summit and was drifting W and SW, and ash between 13.7-19.2 km (45,000-63,000 ft) a.s.l. continued to be identified drifting WNW at least through 0940 on 1 May. Ash plumes continued to be identified in satellite images, rising to 3 km (10,000 ft) a.s.l. and drifting N and SE at least through 1240 on 1 May.

According to a news report the eruption and the presence of ash and ashfall caused the closure of seven airports, scheduled to reopen on 1 May: the Sam Ratulangi International Airport (98 km SW in Manado, North Sulawesi), the Gorontalo Airport (371 km SW), the Siau/Sitaro Airport (40 km N), the Bolaang Mongondow Airport (215 km SW), the Tahuna/Naha Airport (150 km N), the Pohuwato Airport (445 SW), and the Pogogul Airport (460 km WSW). On 1 May about 123 residents were evacuated to Bitung City by boat. Ashfall was notable at the Sam Ratulangi International Airport with delays affecting about 7,000 passengers.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM); Badan Nacional Penanggulangan Bencana (BNPB); Darwin Volcanic Ash Advisory Centre (VAAC); Andrew Tupper, Natural Hazards Consulting; Antara News; Antara News; Antara News; Antara News; Antara News


17 April-23 April 2024 Citation IconCite this Report

PVMBG raised the Alert Level for Ruang to 2 (on a scale of 1-4) at 1300 on 16 April due to intensifying seismicity. A minor eruption began at around 1337 on 16 April and produced dense white emissions; at 1600 the Alert Level was raised to 3 (on a scale of 1-4). Explosive activity began at 2145 and ash plumes rose 2 km above the summit. Activity continued to escalate. An explosive pulse was recorded at 0108 on 17 April. According to the Darwin VAAC ash plumes had risen to 9.1 km (30,000 ft) a.s.l. and drifted W by 0230, and at 0300 they reached 12.2 km (40,000 ft) a.s.l. and detached from the summit. Ash plumes at a lower altitude of 4.6 km (15,000 ft) a.s.l. drifted WSW. BNPB reported that 828 people from Pumpente and Laingpatehi villages evacuated to neighboring Tagulandang Island to the NE and the communication network in Laingpatehi village was non-operational. Photos showed incandescent material being ejected above the summit, incandescent material on the flanks, pyroclastic density currents descending the flanks, and dense ash plumes with lightning rising into dark, nighttime skies. Another explosive pulse was recorded at 0505 according to PVMBG, and the VAAC noted that by 0600 ash plumes had risen to 13.7 km (45,000 ft) a.s.l. and drifted W and NW. The plume was detached from the summit by 0713. Additional smaller eruptive events produced ash plumes that rose to 1.5 km (5,000 ft) a.s.l. and drifted E.

PVMBG recorded bigger eruptive pulses at 1800 and 2015 on 17 April. Roaring and booming noises were sometimes heard, with gray-to-black ash plumes at 2015 and a felt earthquake. According to the VAAC ash plumes rose to 15.2 km (50,000 ft) a.s.l. by 2000 and at least to 19.2 km (63,000 ft) a.s.l. by 2020; the plumes drifted NW. PVMBG raised the Alert Level to 4, the highest level, at 2100 on 17 April noting that seismicity continued to increase, ash plumes were getting taller, and incandescent rocks were ejected as far as 5 km with some reaching Tagulandang Island. The public was warned to stay 6 km away from Ruang’s main crater. Several residents in Tagulandang were hit with tephra and some received medical treatment according to BNPB. Ashfall was recorded in as many as 10 villages in two sub-districts on Tagulandang and in several sub-districts of North Minahasa Regency (75 km SSW) including West Likupang, Wori, East Likupang, and South Likupang. Communication networks in Lumbo Village on Tagulandang were not properly functioning. An estimated 6,045 people living in the W part Tagulandang evacuated. According to a news article, there was damage to more than 3,000 homes, two churches, and an elementary school.

Multiple ash layers were identified in a satellite image 2310 on 17 April according to the VAAC; ash at 16.8 km (55,000 ft) a.s.l. drifted NW and E and ash at 14.3 km (47,000 ft) a.s.l. drifted WSW. At 0310 on 18 April ash plumes rose to 12.2 km and drifted WNW and W and detached from the volcano by 0600; earlier high-level plumes continued to expand as they drifted NW. According to a news report the Sam Ratulangi International Airport, 98 km SW in Manado, North Sulawesi, closed on 18 April due to the presence of ash.

The VAAC continued to track the plumes; lower-altitude plumes at 7.6 km (25,000 ft) a.s.l. drifted SE. The higher plumes, between 10.7-15.2 km (35,000-50,000 ft) a.s.l., continued to drift NW and WNW and had dissipated by 1710 on 19 April, though sulfur dioxide continued to be tracked W. Weather clouds began to obscure the plumes. On 19 April PVMBG reported that ash plumes rose 400-750 m above the summit and drifted S. During 20-21 April the VAAC issued notifications of ash plumes rising 1.5-2.1 km (5,000-7,000 ft) a.s.l. and drifting S and SW based on satellite images and information from PVMBG. The closure of the Sam Ratulangi International Airport affected 150 flights and about 19,085 passengers as of 20 April based on a news report; the airport resumed operations at noon on 22 April. PVMBG reported that during 21-23 April dense white steam-and-gas plumes rose as high as 200 m and drifted SW, W, and NW. The Alert Level was lowered to 3 at 0900 on 22 April because activity had decreased. Residents were warned to stay 4 km away from the crater.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM); Badan Nacional Penanggulangan Bencana (BNPB); Darwin Volcanic Ash Advisory Centre (VAAC); Antara News; Antara News; Tempo; VOI


10 April-16 April 2024 Citation IconCite this Report

PVMBG reported that the number of deep volcanic earthquakes at Ruang increased each day during 10-15 April, with the total number significantly higher than from the entire month of March. During the morning of 16 April dense white plumes were visible rising 200-500 m above the summit and seismicity intensified. At 1000 on 16 April the Alert Level was raised to 2 (on a scale of 1-4) and the public was warned to stay 2 km away from the crater.

A minor eruption began at around 1337 on 16 April. The Darwin VAAC noted that an ash plume was visible in a satellite image rising to 1.2 km (4,000 ft) a.s.l. and drifting SSW. At 1600 the Alert Level was raised to 3. According to a news article a larger eruption began at 2045 and ash plumes rose 2 km. The eruption intensified overnight during 16-17 April. The Darwin VAAC report that at 0230 on 17 April ash plumes rose to 9.1 km (30,000 ft) a.s.l. and drifted W; another plume at 0300 reached 12.2 km (40,000 ft) a.s.l. and detached from the summit. Ash plumes at a lower altitude, 4.6 km (15,000 ft) a.s.l., drifted WSW. At 0600 ash plumes rose to 13.7 km (45,000 ft) a.s.l. and drifted W and NW. The plume was detached from the summit by 0713. BNPB reported that 828 people evacuated and the communication network in Laingpatehi village was not operational. Photos showed incandescent material being ejected above the summit, incandescent material on the flanks, and dense ash plumes with lightning rising into dark, nighttime skies.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM); Badan Nacional Penanggulangan Bencana (BNPB); Jakarta Post; Darwin Volcanic Ash Advisory Centre (VAAC)


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


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: 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.

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 13 confirmed Holocene eruptive periods.

2024 Apr 16 - 2024 Jun 6 (continuing) Confirmed Eruption  

Episode 1 | Eruption
2024 Apr 16 - 2024 Jun 6 (continuing) Evidence from Observations: Reported

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

Episode 1 | Eruption
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
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 VEI: 2

Episode 1 | Eruption
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 VEI: 2

Episode 1 | Eruption 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 VEI: 3 (?)

Episode 1 | Eruption
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 VEI: 1

Episode 1 | Eruption
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 VEI: 2

Episode 1 | Eruption
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 VEI: 2

Episode 1 | Eruption
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 VEI: 3 (?)

Episode 1 | Eruption
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 VEI: 1

Episode 1 | Eruption
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 VEI: 2

Episode 1 | Eruption
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 VEI: 2

Episode 1 | Eruption
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 VEI: 2

Episode 1 | Eruption
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

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 Ruang in the Smithsonian's NMNH Department of Mineral Sciences Rock and Ore collection.

External Sites