Tambora

Photo of this volcano
  • Country
  • Volcanic Region
  • Primary Volcano Type
  • Last Known Eruption
  • 8.25°S
  • 118°E

  • 2850 m
    9348 ft

  • 264040
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

Most Recent Weekly Report: 3 April-9 April 2013 Citation IconCite this Report


Based on visual observations and seismic data, CVGHM raised the Alert Level for Tambora to 2 (on a scale of 1-4) on 5 April.

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


Most Recent Bulletin Report: August 2011 (BGVN 36:08) Citation IconCite this Report


Increased seismicity and minor steam venting in 2011

Beginning in April 2011, Tambora volcano, Indonesia (figure 1), experienced increased seismic activity and minor steam venting. As a result, the Center for Volcanology and Geological Hazard Mitigation (CVGHM) raised the Alert Level for Tambora. This report will summarize the increased activity from April 2011 through 8 September 2011, as reported by CVGHM.

Figure (see Caption) Figure 1. Regional (top) and local (bottom) geographic setting of Tambora volcano, Indonesia. Courtesy of Wilford (2006) and the New York Times.

Seismicity at Tambora increased steadily from April 2011 to at least 8 September. CVGHM reported six seismic signals that were monitored: volcanic earthquakes (VA), shallow volcanic earthquakes (VB), distant tectonic earthquakes (TJ), local tectonic earthquakes (TL), low-frequency earthquakes (LF), and volcanic tremor. Seismic activity from April through August is summarized in figure 2. In addition to increased seismicity, ground-based observers described dense white plumes rising 50-75 m above the caldera rim in April and June.

Figure (see Caption) Figure 2. Reported seismic activity at Tambora cumulative by month from April through August 2011. Onset of continuous volcanic tremor on 29 August is not represented. Data from CVGHM.

Volcanic tremor started 29 August and continued every day since, with the exception of 3 September (table 1). The tremor was accompanied by diffuse plumes rising 10-20 m above the caldera rim on 29 August and 5 September. Based on seismic activity and visual observations, CVGHM raised the Alert Level to 2 (on a scale from 1 to 4) on 30 August, and forbade access to the peak of Tambora.

Table 1. Summary of seismicity at Tambora since the onset of volcanic tremor on 29 August 2011. On both 29 August and 5 September seismicity was accompanied by plumes rising 10-20 m above the caldera rim. Data from CVGHM.

[Skip text table]
    Date             Volcanic       Volcanic        Local       Low-frequency      Tremor
                      A-type         B-type       tectonic       earthquakes
                   earthquakes    earthquakes    earthquakes

    29 Aug 2011        14              -              3               -          continuous
    30 Aug 2011         9              5              2               1          continuous
    31 Aug 2011         6              5              -               2          continuous
    01 Sep 2011        15              -              2               2          continuous
    02 Sep 2011         6              4              4               6              11
    03 Sep 2011         5              5              4               4               -
    04 Sep 2011         6              1              3               4              11
    05 Sep 2011        11              7              3               1               4
    06 Sep 2011         7              4              -               -          continuous
    07 Sep 2011        40              6              1               -          continuous


Along with the continuation of the tremor after 29 August, CVGHM reported an increase in other types of seismic activity from 30 August to 7 September. On 5 September an earthquake was felt by residents (exact location undisclosed). Instruments recorded 40 volcanic earthquakes on 7 September (table 1); 32 of those were recorded within 6 hours. On 8 September, CVGHM raised the Alert Level to 3, invoked a 3 km exclusion zone, and prohibited access to Disaster Prone Areas III, summarized in table 2. The Disaster Prone Areas were largely based on the devastating 1815 eruption of Tambora. As of 21 September, the Alert Level remained at 3.

Table 2. Summary of Disaster Prone Areas at Tambora defined on the basis of radial distance from the peak of Tambora. Courtesy of CVGHM.

[Skip text table]
    Area                           Radius      Potential hazards
                               from Tambora

    Disaster Prone Area I          8 km        Lahars, ash fall, and incandescent bombs.
    Disaster Prone Area II         5 km        Pyroclastic flows, lava flows, toxic gases,
                                                 incandescent bombs, ash fall, lahars/mudflows,
                                                 and high acidity in water.
    Disaster Prone Area III        3 km        Pyroclastic flows, lava flows, toxic gases,
                                                 incandescent bombs, and heavy ash fall.

References. Wilford, J.N., 2006, Under an 1815 Volcano Eruption, Remains of a 'Lost Kingdom', the New York Times, URL: http://www.nytimes.com/2006/02/28/science/28volc.html; Posted 28 February 2006; accessed 26 September 2011.

Information Contacts: Center for Volcanology and Geological Hazard Mitigation (CVGHM), Jl. Diponegoro 57, Bandung, West Java, Indonesia, 40 122 (URL: http://www.vsi.esdm.go.id/).

Weekly Reports - Index


2013: April
2012: April
2011: August | September | October


3 April-9 April 2013 Citation IconCite this Report


Based on visual observations and seismic data, CVGHM raised the Alert Level for Tambora to 2 (on a scale of 1-4) on 5 April.

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


4 April-10 April 2012 Citation IconCite this Report


CVGHM reported that during January-8 April plumes did not rise from Tambora, no changes were observed around the caldera, and seismicity decreased. On 9 April 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)


12 October-18 October 2011 Citation IconCite this Report


CVGHM reported that during 22 September-9 October plumes did not rise from Tambora; seismicity fluctuated, but declined overall. Based on visual observations, deformation data, and seismicity, the Alert Level was lowered to 2 (on a scale of 1-4) on 9 October.

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


7 September-13 September 2011 Citation IconCite this Report


Based on visual observation and seismic data, CVGHM reported an increase in activity at Tambora that started in April. Therefore, on 30 August, the Alert Level was raised to 2 (on a scale of 1-4). During 30 August-8 September seismicity continued to increase. Diffuse white plumes were observed on 5 September and rose 10 m above the crater rim. On 8 September the Alert Level was raised to 3 (on a scale of 1-4).

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


24 August-30 August 2011 Citation IconCite this Report


Based on visual observation and seismic data, CVGHM reported an increase in activity at Tambora during the previous five months. Ground-based observers at an observation post in Tambora village noted dense white plumes rising 50-75 m above the caldera rim during April and June, but no plumes during May or July. In August dense white plumes rose 20 m above the caldera rim. Seismicity started to increase in April and continued to increase through August. On 30 August the Alert Level was raised to 2 (on a scale of 1-4).

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.

08/2011 (BGVN 36:08) Increased seismicity and minor steam venting in 2011




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


August 2011 (BGVN 36:08) Citation IconCite this Report


Increased seismicity and minor steam venting in 2011

Beginning in April 2011, Tambora volcano, Indonesia (figure 1), experienced increased seismic activity and minor steam venting. As a result, the Center for Volcanology and Geological Hazard Mitigation (CVGHM) raised the Alert Level for Tambora. This report will summarize the increased activity from April 2011 through 8 September 2011, as reported by CVGHM.

Figure (see Caption) Figure 1. Regional (top) and local (bottom) geographic setting of Tambora volcano, Indonesia. Courtesy of Wilford (2006) and the New York Times.

Seismicity at Tambora increased steadily from April 2011 to at least 8 September. CVGHM reported six seismic signals that were monitored: volcanic earthquakes (VA), shallow volcanic earthquakes (VB), distant tectonic earthquakes (TJ), local tectonic earthquakes (TL), low-frequency earthquakes (LF), and volcanic tremor. Seismic activity from April through August is summarized in figure 2. In addition to increased seismicity, ground-based observers described dense white plumes rising 50-75 m above the caldera rim in April and June.

Figure (see Caption) Figure 2. Reported seismic activity at Tambora cumulative by month from April through August 2011. Onset of continuous volcanic tremor on 29 August is not represented. Data from CVGHM.

Volcanic tremor started 29 August and continued every day since, with the exception of 3 September (table 1). The tremor was accompanied by diffuse plumes rising 10-20 m above the caldera rim on 29 August and 5 September. Based on seismic activity and visual observations, CVGHM raised the Alert Level to 2 (on a scale from 1 to 4) on 30 August, and forbade access to the peak of Tambora.

Table 1. Summary of seismicity at Tambora since the onset of volcanic tremor on 29 August 2011. On both 29 August and 5 September seismicity was accompanied by plumes rising 10-20 m above the caldera rim. Data from CVGHM.

[Skip text table]
    Date             Volcanic       Volcanic        Local       Low-frequency      Tremor
                      A-type         B-type       tectonic       earthquakes
                   earthquakes    earthquakes    earthquakes

    29 Aug 2011        14              -              3               -          continuous
    30 Aug 2011         9              5              2               1          continuous
    31 Aug 2011         6              5              -               2          continuous
    01 Sep 2011        15              -              2               2          continuous
    02 Sep 2011         6              4              4               6              11
    03 Sep 2011         5              5              4               4               -
    04 Sep 2011         6              1              3               4              11
    05 Sep 2011        11              7              3               1               4
    06 Sep 2011         7              4              -               -          continuous
    07 Sep 2011        40              6              1               -          continuous


Along with the continuation of the tremor after 29 August, CVGHM reported an increase in other types of seismic activity from 30 August to 7 September. On 5 September an earthquake was felt by residents (exact location undisclosed). Instruments recorded 40 volcanic earthquakes on 7 September (table 1); 32 of those were recorded within 6 hours. On 8 September, CVGHM raised the Alert Level to 3, invoked a 3 km exclusion zone, and prohibited access to Disaster Prone Areas III, summarized in table 2. The Disaster Prone Areas were largely based on the devastating 1815 eruption of Tambora. As of 21 September, the Alert Level remained at 3.

Table 2. Summary of Disaster Prone Areas at Tambora defined on the basis of radial distance from the peak of Tambora. Courtesy of CVGHM.

[Skip text table]
    Area                           Radius      Potential hazards
                               from Tambora

    Disaster Prone Area I          8 km        Lahars, ash fall, and incandescent bombs.
    Disaster Prone Area II         5 km        Pyroclastic flows, lava flows, toxic gases,
                                                 incandescent bombs, ash fall, lahars/mudflows,
                                                 and high acidity in water.
    Disaster Prone Area III        3 km        Pyroclastic flows, lava flows, toxic gases,
                                                 incandescent bombs, and heavy ash fall.

References. Wilford, J.N., 2006, Under an 1815 Volcano Eruption, Remains of a 'Lost Kingdom', the New York Times, URL: http://www.nytimes.com/2006/02/28/science/28volc.html; Posted 28 February 2006; accessed 26 September 2011.

Information Contacts: Center for Volcanology and Geological Hazard Mitigation (CVGHM), Jl. Diponegoro 57, Bandung, West Java, Indonesia, 40 122 (URL: http://www.vsi.esdm.go.id/).

Eruptive History


Summary of Holocene eruption dates and Volcanic Explosivity Indices (VEI).


Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
1967 ± 20 years Unknown Confirmed 0 Historical Observations NE part of caldera floor
1880 ± 30 years Unknown Confirmed 2 Historical Observations SW part of caldera (Doro Afi Toi)
1819 Aug Unknown Confirmed 2 Historical Observations
1812 1815 Jul 15 (?) Confirmed 7 Historical Observations
0740 ± 150 years Unknown Confirmed   Radiocarbon (uncorrected)
3050 BCE (?) Unknown Confirmed   Radiocarbon (uncorrected)
3910 BCE ± 200 years Unknown Confirmed   Radiocarbon (uncorrected)

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.

Photo Gallery


Tambora's serrated NE caldera rim towers 1250 m above the caldera floor. The 6-km-wide caldera was formed in 1815, during one of the world's most powerful eruptions of the past 10,000 years. Since 1815 only a few minor eruptions have occurred on the caldera floor.

Photo by Rizal Dasoeki, 1986 (Volcanological Survey of Indonesia).
See title for photo information.
Tambora's caldera, seen here from the western rim, was formed during the eruption of 1815 following the ejection of about 150 cu km of airfall tephra and pyroclastic flows. This was history's largest explosive eruption, and occurred following low-level eruptive activity that began in 1812. Only a few minor eruptions have taken place since formation of the 6-km-wide and 1250-m-deep caldera. The caldera rim is rarely visited and the last eruption, producing a blocky lava flow on the caldera floor, is known only to have occurred sometime between 1947 and 1968.

Photo by Rizal Dasoeki, 1986 (Volcanological Survey of Indonesia).
See title for photo information.
The bottom portion of this cliff section in the center of the western wall of the Tambora caldera shows a thick sequence of bedded lava flows that filled an earlier Tambora caldera formed 43,000 years ago. The even-textured sloping surface above it consists of pyroclastic material erupted between about 5900 and 1210 years ago. This is overlain (upper right) by another cliff-forming unit, about 200 m thick, produced during the 1815 eruption. These upper cliffs expose airfall-pumice deposits at the base, above which is a thick sequence of pyroclastic-flow deposits.

Photo by Rizal Dasoeki, 1986 (Volcanological Survey of Indonesia).
See title for photo information.
Tambora volcano on Indonesia's Sumbawa Island was the site of the world's largest historical eruption in April 1815. This NASA Landsat mosaic shows the 6-km-wide caldera truncating the 2850-m-high summit of the massive volcano. Pyroclastic flows during the 1815 eruption reached the sea on all sides of the 60-km-wide volcanic peninsula, and the ejection of large amounts of tephra caused world-wide temperature declines in 1815 and 1816.

NASA Landsat7 image (worldwind.arc.nasa.gov)
See title for photo information.

Smithsonian Sample Collections Database


The following 1 samples associated with this volcano can be found in the Smithsonian's NMNH Department of Mineral Sciences collections. Catalog number links will open a window with more information.

Catalog Number Sample Description
NMNH 116570 Pumice

Affiliated Sites