Novarupta

Photo of this volcano
  • United States
  • Alaska
  • Caldera
  • 1912 CE
  • Country
  • Volcanic Region
  • Primary Volcano Type
  • Last Known Eruption
  • 58.27°N
  • 155.157°W

  • 841 m
    2758 ft

  • 312180
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

Most Recent Weekly Report: 8 November-14 November 2017 Citation IconCite this Report


On 13 November AVO reported that a cloud of ash, resuspended by strong winds in the vicinity of Katmai and the Valley of Ten Thousand Smokes, was blown about 120 km SE over Shelikof Strait and Kodiak Island at an altitude of up to 3 km (10,000 ft) a.s.l. The ash was originally deposited during the Novarupta eruption in 1912. The Volcano Alert Level remained at Normal and the Aviation Color Code remained at Green.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


Most Recent Bulletin Report: September 2003 (BGVN 28:09) Citation IconCite this Report


Strong winds resuspend old ash deposits, causing a large plume and distant ashfall

According to the National Weather Service, strong winds in the Katmai area on 21 September 2003 picked up old, loose volcanic ash and carried it E. Reports of minor ashfall were reported from Kodiak Island, ~ 100 km from Katmai. This phenomenon was not the result of volcanic activity and no eruption occurred.

Andrea Steffke of the Geophysical Institute, University of Alaska Fairbanks, reported a relatively large ash cloud observed in satellite images coming from the Katmai area on 21 September 2003. The cloud was first seen in satellite imagery (AVHRR, GOES, and MODIS) extending ~ 69 km to the SE. The maximum temperature difference observed was -1.46°C. Dave Schneider of the Alaska Volcano Observatory reported on 22 September 2003 that at its greatest extent the cloud was detectable for ~ 400 km. It was initially observed by an overflying (high-altitude) jet, and subsequently identified in split-window images from AVHRR, MODIS, and GOES satellites. Additional pilot reports placed the cloud top at ~ 2.1 km altitude.

The Katmai Group of volcanoes are seismically monitored by AVO, so it was possible to quickly confirm that an eruption had not taken place. SIGMETS were issued by the Alaska Aviation Weather Unit (AAWU) for this event and an AVO Information Release was distributed that indicated that this cloud of re-suspended ash was potentially hazardous to aircraft. This event is unusual in its intensity and extent of transport. The Katmai region is characterized by frequent high winds that can be strong enough to re-suspend large (several centimeters in size) pumice fragments, yet these events typically don't produce large, extensive airborne ash clouds.

Information Contacts: Alaska Volcano Observatory (AVO), a cooperative program of the U.S. Geological Survey, 4200 University Drive, Anchorage, AK 99508-4667, USA (URL: http://www.avo.alaska.edu/), the Geophysical Institute, University of Alaska, PO Box 757320, Fairbanks, AK 99775-7320, USA, and the Alaska Division of Geological and Geophysical Surveys, 794 University Ave., Suite 200, Fairbanks, AK 99709, USA.

Weekly Reports - Index


2017: November
2016: December
2011: May
2010: November
2005: November
2003: September


8 November-14 November 2017 Citation IconCite this Report


On 13 November AVO reported that a cloud of ash, resuspended by strong winds in the vicinity of Katmai and the Valley of Ten Thousand Smokes, was blown about 120 km SE over Shelikof Strait and Kodiak Island at an altitude of up to 3 km (10,000 ft) a.s.l. The ash was originally deposited during the Novarupta eruption in 1912. The Volcano Alert Level remained at Normal and the Aviation Color Code remained at Green.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


7 December-13 December 2016 Citation IconCite this Report


According to NASA's Earth Observatory, a Moderate Resolution Imaging Spectroradiometer (MODIS) satellite image acquired on 2 December of the Katmai area showed a plume of re-suspended ash which had been deposited during the 1912 eruption.

Source: NASA Earth Observatory


11 May-17 May 2011 Citation IconCite this Report


Based on analysis of satellite imagery, pilot observations, KVERT reports, and information from AVO, the Anchorage VAAC reported that on 11 May strong winds in the Katmai area re-suspended loose ash deposited during the 1912 eruption. The Volcano Alert Level remained at Normal and the Aviation Color Code remained at Green.

Source: Anchorage Volcanic Ash Advisory Center (VAAC)


24 November-30 November 2010 Citation IconCite this Report


Based on analysis of satellite imagery and information from AVO, the Anchorage VAAC reported that on 29 November strong winds in the Katmai area picked up loose ash deposited during the 1912 eruption and carried it SE over Kodiak Island. The Volcano Alert Level remained at Normal and the Aviation Color Code remained at Green.

Source: Anchorage Volcanic Ash Advisory Center (VAAC)


2 November-8 November 2005 Citation IconCite this Report


Strong winds in the Katmai area picked up loose ash deposited during the 1912 eruption and carried it E over Kodiak Island. AVO recorded a large area of resuspended ash on satellite imagery. The National Weather Service estimated that the top of the plume was at 1.5 km (5,000 ft) a.s.l. Katmai remained at Concern Color Code Green.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


17 September-23 September 2003 Citation IconCite this Report


According to the National Weather Service, strong winds on 21 September in the Katmai area picked up old, loose volcanic ash and carried it E over Kodiak Island. AVO received reports that some of this material fell in Kodiak. This was not the result of volcanic activity and no eruption occurred. Re-suspended volcanic ash should be considered as hazardous as primary volcanic ash, and a threat to aircraft. The volcanoes in the Katmai cluster remained at Concern Color Code Green.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


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.

09/2003 (BGVN 28:09) Strong winds resuspend old ash deposits, causing a large plume and distant ashfall




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


September 2003 (BGVN 28:09) Citation IconCite this Report


Strong winds resuspend old ash deposits, causing a large plume and distant ashfall

According to the National Weather Service, strong winds in the Katmai area on 21 September 2003 picked up old, loose volcanic ash and carried it E. Reports of minor ashfall were reported from Kodiak Island, ~ 100 km from Katmai. This phenomenon was not the result of volcanic activity and no eruption occurred.

Andrea Steffke of the Geophysical Institute, University of Alaska Fairbanks, reported a relatively large ash cloud observed in satellite images coming from the Katmai area on 21 September 2003. The cloud was first seen in satellite imagery (AVHRR, GOES, and MODIS) extending ~ 69 km to the SE. The maximum temperature difference observed was -1.46°C. Dave Schneider of the Alaska Volcano Observatory reported on 22 September 2003 that at its greatest extent the cloud was detectable for ~ 400 km. It was initially observed by an overflying (high-altitude) jet, and subsequently identified in split-window images from AVHRR, MODIS, and GOES satellites. Additional pilot reports placed the cloud top at ~ 2.1 km altitude.

The Katmai Group of volcanoes are seismically monitored by AVO, so it was possible to quickly confirm that an eruption had not taken place. SIGMETS were issued by the Alaska Aviation Weather Unit (AAWU) for this event and an AVO Information Release was distributed that indicated that this cloud of re-suspended ash was potentially hazardous to aircraft. This event is unusual in its intensity and extent of transport. The Katmai region is characterized by frequent high winds that can be strong enough to re-suspend large (several centimeters in size) pumice fragments, yet these events typically don't produce large, extensive airborne ash clouds.

Information Contacts: Alaska Volcano Observatory (AVO), a cooperative program of the U.S. Geological Survey, 4200 University Drive, Anchorage, AK 99508-4667, USA (URL: http://www.avo.alaska.edu/), the Geophysical Institute, University of Alaska, PO Box 757320, Fairbanks, AK 99775-7320, USA, and the Alaska Division of Geological and Geophysical Surveys, 794 University Ave., Suite 200, Fairbanks, AK 99709, USA.

The Global Volcanism Program has no synonyms or subfeatures listed for Novarupta.

Eruptive History


There is data available for 3 Holocene eruptive periods.

Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
[ 1950 Jul 5 ± 4 days ] [ Unknown ] Discredited    
[ 1949 May 19 ] [ Unknown ] Discredited    
1912 Jun 6 1912 Oct (?) Confirmed 6 Historical Observations

Deformation History


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


Deformation during 1995 - 2010 [Subsidence; Observed by InSAR]

Start Date: 1995 Stop Date: 2010 Direction: Subsidence Method: InSAR
Magnitude: Unknown Spatial Extent: 5.00 km Latitude: 58.000 Longitude: -155.000

Remarks: Localized subsidence on the Novarupta dome is likely due to thermoelastic contraction of the dome and thick ashflow tuff. There is a gap in InSAR data coverage between 2000 and 2004, but the subsidence is likely continuous.

Figure (see Caption)

Averaged deformation images of the Mount Martin?Mount Mageik area produced by stacking high- quality ERS-1 and ERS-2 interferograms for 1995?2000 from two ascending tracks, 021 and 250. Ellipse outlines an area of subsidence near Novarupta dome. A full cycle of colors (i.e., one interferometric fringe) represents 28 mm/year of LOS surface displacement. Areas of loss of InSAR coherence are not colored. See Fig. 6.197 for meanings of labels

From: Lu and Dzurisin 2014.


Reference List: Lu and Dzurisin 2014.

Full References:

Lubis, A. M., 2014. Uplift of Kelud Volcano Prior to the November 2007 Eruption as Observed by L-Band Insar. Journal of Engineering and Technological Sciences, 46(3), 245-257.

Emission History


There is no Emissions History data available for Novarupta.

Photo Gallery


A 65-m-high, 380-m-wide lava dome lies within a circular ejecta ring and caps the 1912 vent of Novarupta volcano. A 60-hour-long eruption beginning on June 6, 1912, the Earth's largest eruption during the 20th century, produced The Valley of Ten Thousand Smokes ash-flow deposit, which forms the flat ground at the right. The face of Falling Mountain, behind Novarupta dome, was sheared off by a 2-km-wide collapse around the Novarupta vent. This view from the NE shows snow-capped Mageik volcano in the background.

Photo by Tom Miller (U.S. Geological Survey, Alaska Volcano Observatory).
See title for photo information.
Mount Mageik (left) and steaming Mount Martin (distant right) tower above the flat-bottomed floor of the Valley of Ten Thousand Smokes (VTTS). The VTTS was formed by ash flows during the 1912 eruption of Novarupta volcano, the Earth's largest eruption of the 20th century. Glacier-clad Mount Mageik has a broad summit capped by 4 knobs, each of which is a spatter and lava-flow vent.

Photo by Game McGimsey (U.S. Geological Survey, Alaska Volcano Observatory).
See title for photo information.

Smithsonian Sample Collections Database


The following 14 samples associated with this volcano can be found in the Smithsonian's NMNH Department of Mineral Sciences collections, and may be availble for research (contact the Rock and Ore Collections Manager). Catalog number links will open a window with more information.

Catalog Number Sample Description Lava Source Collection Date
NMNH 108924 Rhyolite -- --
NMNH 116660-1 Andesite-Dacite Pumice -- --
NMNH 116660-2 Andesite-Dacite Pumice -- --
NMNH 116660-3 Andesite Pumice -- --
NMNH 116660-5 Rhyolite Pumice -- --
NMNH 117233-84 Tuff -- --
NMNH 117233-85 Tuff -- --
NMNH 117233-86 Tuff -- --
NMNH 117233-87 Tuff -- --
NMNH 117259-20 Fumarole Deposit -- --
NMNH 117259-21 Fumarole Deposit -- --
NMNH 117259-22 Fumarole Deposit -- --
NMNH 117259-23 Fumarole Deposit -- 2 Aug 1919
NMNH 117259-24 Fumarole Deposit -- 2 Aug 1919

Affiliated Sites