Katmai

Photo of this volcano
  • United States
  • Alaska
  • Stratovolcano
  • 1912 CE
  • Country
  • Volcanic Region
  • Primary Volcano Type
  • Last Known Eruption
  • 58.28°N
  • 154.963°W

  • 2047 m
    6714 ft

  • 312170
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

Most Recent Weekly Report: 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)


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


2011: May
2010: November
2005: November
2003: September


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.

Eruptive History


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


Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
[ 1931 May 8 ] [ 1931 Jul ] Discredited    
[ 1929 Dec ] [ Unknown ] Discredited    
[ 1921 Nov 27 ] [ Unknown ] Discredited    
[ 1920 Mar 9 ] [ Unknown ] Discredited    
[ 1914 Jul ] [ Unknown ] Discredited    
1912 Jun 6 1912 Jul 21 (in or after) Confirmed 3 Historical Observations

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


Katmai caldera, a collapse feature formed during the catastrophic eruption of the nearby Novarupta vent in June 1912 is seen here in an aerial view from the NE. The steep-walled, 1.5-km-wide Katmai caldera truncates a formerly 2290-m-high cluster of overlapping stratovolcanoes. The caldera is partially filled by a blue-green lake that is about 250 m deep and rising. Beyond the caldera are the multiple peaks of Trident volcano; Mageik volcano is the snow-and-ice-covered cone on the skyline.

Photo by Chris Nye, 1991 (Alaska Division of Geological and Geophysical Surveys, Alaska Volcano Observatory).
See title for photo information.
Katmai caldera, seen here from its west rim, is a 3 x 4.5 km wide caldera that formed in 1912. Little if any eruptive activity took place at Katmai itself, which prior to collapse was a complex of 4 small overlapping stratovolcanoes. Hydraulic draining of magma away from Katmai to Novarupta volcano (10 km to the west) during the catastrophic 1912 eruption caused the collapse of the unsupported summit(s) of Katmai. The 250-m-deep caldera lake covers a small lava dome and tuff ring that were erupted on the floor of the caldera.

Photo by Game McGimsey, 1990 (Alaska Volcano Observatory, U.S. Geological Survey).
See title for photo information.

Smithsonian Sample Collections Database


The following 76 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 116509-1 Glass
NMNH 116509-10 Andesite
NMNH 116509-11 Glass
NMNH 116509-12 Basalt
NMNH 116509-13 Glass
NMNH 116509-14 Basalt
NMNH 116509-15 Dyke rock
NMNH 116509-16 Obsidian
NMNH 116509-17 Rhyolite
NMNH 116509-18 Tuff
NMNH 116509-19 Basalt
NMNH 116509-2 Syenite
NMNH 116509-20 Obsidian
NMNH 116509-21 Granite
NMNH 116509-22 Lava
NMNH 116509-23 Quartz-porphyry
NMNH 116509-24 Glass
NMNH 116509-25 Dacite
NMNH 116509-26 Rhyolite
NMNH 116509-3 Pumice
NMNH 116509-4 Glass
NMNH 116509-5 Quartz-porphyry
NMNH 116509-6 Andesite
NMNH 116509-7 Trachyte
NMNH 116509-8 Tuff
NMNH 116509-9 Pumice
NMNH 116550-1 Pumice
NMNH 116550-10 Granite
NMNH 116550-2 Pumice
NMNH 116550-3 Pumice
NMNH 116550-4 Tuffaceous-sand
NMNH 116550-5 Tuffaceous-sand
NMNH 116550-6 Pumice
NMNH 116550-7 Pumice
NMNH 116550-8 Pumice
NMNH 116550-9 Pumice
NMNH 116660-4 Dacite pumice
NMNH 117259-1 Fumarole deposit
NMNH 117259-10 Fumarole deposit
NMNH 117259-11 Fumarole deposit
NMNH 117259-12 Fumarole deposit
NMNH 117259-13 Fumarole deposit
NMNH 117259-14 Fumarole deposit
NMNH 117259-15 Fumarole deposit
NMNH 117259-16 Fumarole deposit
NMNH 117259-17 Fumarole deposit with halite and opal
NMNH 117259-18 "Fumarole deposit with opal, pyrite, and others"
NMNH 117259-19 Fumarole deposit with pyrite and marcasite
NMNH 117259-2 Fumarole deposit
NMNH 117259-25 Fumarole deposit
NMNH 117259-26 Fumarole deposit
NMNH 117259-27 Fumarole deposit
NMNH 117259-28 Fumarole deposit
NMNH 117259-29 Fumarole deposit
NMNH 117259-3 Fumarole deposit
NMNH 117259-30 Fumarole deposit
NMNH 117259-31 Fumarole deposit
NMNH 117259-32 Fumarole deposit
NMNH 117259-33 Fumarole deposit
NMNH 117259-34 Fumarole deposit
NMNH 117259-35 Fumarole deposit
NMNH 117259-36 Fumarole deposit
NMNH 117259-37 Fumarole deposit
NMNH 117259-38 Fumarole deposit
NMNH 117259-39 Fumarole deposit
NMNH 117259-4 Fumarole deposit
NMNH 117259-40 Fumarole deposit
NMNH 117259-41 Fumarole deposit
NMNH 117259-42 Fumarole deposit
NMNH 117259-43 Fumarole deposit
NMNH 117259-44 Fumarole deposit
NMNH 117259-5 Fumarole deposit
NMNH 117259-6 Fumarole deposit
NMNH 117259-7 Fumarole deposit
NMNH 117259-8 Fumarole deposit
NMNH 117259-9 Fumarole deposit

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