Griggs
Griggs Eruption Timeline
Griggs
Spurr
Great Sitkin
Akutan
Aniakchak
Atka volcanic complex
Augustine
Cleveland
Dutton
Edgecumbe
Fisher
Gareloi
Great Sitkin
Griggs
Iliamna
Isanotski
Kanaga
Katmai
Little Sitkin
Mageik
Makushin
Martin
Novarupta
Pavlof
Redoubt
Semisopochnoi
Shishaldin
Snowy
Spurr
Takawangha
Tanaga
Trident
Ugashik-Peulik
Ukinrek Maars
Veniaminof
Westdahl
Wrangell
Adagdak
Addington volcanic field
Alagogshak
Amak
Amchixtam Chaxsxii
Amukta
Andrew Bay volcano
Basalt of Gertrude Creek
Behm Canal-Rudyerd Bay
Black Peak
Bobrof
Bogoslof
Buldir
Buzzard Creek
Camille Cone
Capital
Carlisle
Chagulak
Chiginagak
Churchill, Mt
Cone 3110
Cone 3601
Dana
Davidof
Denison
Devils Desk
Double Glacier
Douglas
Drum
Duncan Canal
Emmons Lake Volcanic Center
Espenberg
Folsoms Bluff
Fourpeaked
Frosty
Gas Rocks, the
Gilbert
Gordon
Gosling Cone
Hayes
Herbert
Imuruk Lake Volc Field
Ingakslugwat Hills
Ingenstrem Depression Volcanic Field
Ingrisarak Mtn
Iron Trig cone
Iskut-Unuk River cones
Jarvis
Jumbo Dome
Kagamil
Kaguyak
Kasatochi
Kejulik
Kialagvik
Kiska
Klawasi Group
Knob 1000
Kochilagok Hill
Koniuji
Kookooligit Mountains
Koyuk-Buckland volcanics
Kukak
Kupreanof
Lone basalt
Maclaren River volcanic field
Moffett
Monogenetic QT vents of WWVF
Morzhovoi
Nelson Island
Nunivak Island
Nushkolik Mountain volcanic field
Okmok
Pavlof Sister
Prindle Volcano
Rainbow River cone
Recheshnoi
Roundtop
Sanford
Seguam
Segula
Sergief
Skookum Creek
St. George volcanic field
St. Michael
St. Paul Island
Steller
Stepovak Bay 1
Stepovak Bay 2
Stepovak Bay 3
Stepovak Bay 4
Suemez Island
Table Top Mtn
Tanada Peak
Tanax̂ Angunax̂
Tlevak Strait
Togiak volcanics
Uliaga
Ungulungwak Hill-Ingrichuak Hill
Unnamed (near Ukinrek Maars)
Vsevidof
Western Cones
Wide Bay cone
Yantarni
Yunaska
Legend
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 | Red (Warning) |
| Orange (Watch) |
| Yellow (Advisory) |
| Green (Normal) |
| Uninstrumented |
 | Community |
| Webcam |
| Instrument |
| Earthquake Magnitude | |
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0
7+
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| Earthquake Age | |
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Last 2 Hours |
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Last 2 Days |
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Last 1 Week |
Facts
- Official Name: Mount Griggs
- Seismically Monitored: Yes
- Color Code: GREEN
- Alert Level: NORMAL
- Elevation: 2317m (7601ft)
- Latitude: 58.3572
- Longitude: -155.1037
- Smithsonian VNum: 312190
- Pronunciation:
-
Nearby Towns:
- Karluk 59 mi (96 km) SE
- King Salmon 61 mi (98 km) NW
- Kanatak 64 mi (104 km) SW
- Larsen Bay 70 mi (113 km) SE
- Igiugig 73 mi (117 km) NW
Distance from Anchorage: 268 mi (431 km)
Description
From Wood and Kienle (1990) [1] : "A spectacular, little-dissected cone, Mount Griggs towers 1,700 m above the north margin of the Valley of Ten Thousand Smokes, its summit only 10 km north of Novarupta. Uniquely among the stratovolcanoes of the Katmai district, it lies 10 km behind (northwest of) the remarkably linear (N66E-trending) volcanic front defined by Martin, Mageik, Trident, Katmai, and Snowy Mountain centers."Griggs's truncated summit is an expression of 3 concentric craters, the outermost of which is 1.5 km wide, breached to the southwest, and filled by a semi-annulus of ice wrapped around a young central cone containing the nested inner craters. The main outer crater probably originated by early Holocene collapse, and formation of a 1-cubic km-scale debris avalanche, remnants of which survive on the lower west-southwest flank and across the valley on Broken Mountain. Much of the amphitheater was subsequently filled by the nested inner cone. Outer slopes of the main and inner cones expose a few scoria flows and local scoria falls but principally consist of complexes of the thin brecciated lava tongues, overlapping and bifurcating in the manner so characteristic of summit-fed andesites on steep slopes. The total volume of Mount Griggs is ~25 cubic km.
"Griggs's products are chiefly olivine-pyroxene andesites; 27 samples range continuously from 54.5 to 63.5% SiO2. They are consistently more potassic than products of the other Katmai cluster volcanoes, their K2O contents being 1.3-1.4% at 57.5% SiO2 and 1.7-1.9% at 60%. Isotopic data also suggest a source mixture and plumbing system independent of the other nearby centers.
"Numerous SO2-rich fumarolic jets occur between 1,940-m and 2,180-m elevation atop the inner cone and along a steep chute on its upper southwest slope. Orifice temperatures (measured by Dave Johnston in 1978-9) range from 96 degrees to 108 degrees C, and their condensates have pH ~1. Each orifice is constructing its own mound of sulfur sublimate. Downhill fumaroles are hottest and loudest, their roar commonly audible from the valley floor."
Name Origin
Mount Griggs was named in 1956 by Gilbert Grosvenor, National Geographic Society, for Robert Fiske Griggs (1881-1952), botanist and leader of six National Geographic Society expeditions to the Katma District from 1915 to 1930. These expeditions lead to the 1918 creation of the Katmai National Monument. This volcano was previously called "Knife Peak" (Orth, 1971).
References Cited
[1] Volcanoes of North America: United States and Canada, 1990
Wood, C. A., and Kienle, Juergen, (eds.), 1990, Volcanoes of North America: United States and Canada: New York, Cambridge University Press, 354 p.Current Activity
No new updates for Griggs volcano since March 18, 2022, 3:33 pm.
Recent Updates
Color Code Timeline
Reported Activity
Modern Eruptions
5 Event Date(s)
Past Activity Legend:
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Eruption |
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Questionable eruption |
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Non-eruptive activity |
Map Images
By:
U.S. Geological Survey
Topographic shaded relief map of the southern part of the Katmai area, including Snowy, Griggs, Trident, Novarupta, Falling Mtn., Mt. Cerberus, Martin, and Mageik.
Topographic shaded relief map of the southern part of the Katmai area, including Snowy, Griggs, Trident, Novarupta, Falling Mtn., Mt. Cerberus, Martin, and Mageik.
By:
Miller, T. P.
Geologic map of Katmai Caldera region.
Geologic map of Katmai Caldera region.
By:
U.S. Geological Survey
Topographic map of mountains Martin, Mageik, Falling, Cerberus, Trident, Katmai, and Novarupta vent.
Topographic map of mountains Martin, Mageik, Falling, Cerberus, Trident, Katmai, and Novarupta vent.
By:
Schaefer, J. R. G.
Alaska Peninsula volcanoes.
Alaska Peninsula volcanoes.
By:
Cameron, C. E.
Index map showing the location of the Katmai group volcanoes relative to the State of Alaska and other seismically monitored Alaskan volcanoes. Figure modified from Adleman, Jennifer, 2002, The great eruption of 1912: National Park Service Alaska Park Science Winter 2002, Anchorage, AK, http://www.arlis.org/docs/vol1/52558645/52558645v1no1.pdf , p. 4-11.
Index map showing the location of the Katmai group volcanoes relative to the State of Alaska and other seismically monitored Alaskan volcanoes. Figure modified from Adleman, Jennifer, 2002, The great eruption of 1912: National Park Service Alaska Park Science Winter 2002, Anchorage, AK, http://www.arlis.org/docs/vol1/52558645/52558645v1no1.pdf , p. 4-11.
By:
Schaefer, Janet
Index map showing the location of Quaternary volcanoes on the Alaska peninsula.
Index map showing the location of Quaternary volcanoes on the Alaska peninsula.
Map References
Recently active volcanoes of Alaska, 2023
Cameron, C.E., Bull, K.F., and Macpherson, A.E., 2023, Recently active volcanoes of Alaska: Alaska Division of Geological & Geophysical Surveys Miscellaneous Publication 133 v. 6, 2 sheets. https://doi.org/10.14509/31086.
Historically active volcanoes of Alaska, v. 3, 2018
Cameron, C.E., Schaefer, J.R., and Mulliken, K.M., 2018, Historically active volcanoes of Alaska: Alaska Division of Geological & Geophysical Surveys Miscellaneous Publication 133 v. 3, 2 sheets. Http://doi.org/10.14509/30142
Historically active volcanoes of Alaska, 2014
Schaefer, J.R., Cameron, C.E., and Nye, C.J., 2014, Historically active volcanoes of Alaska: Alaska Division of Geological & Geophysical Surveys Miscellaneous Publication 133 v. 1.2, 1 sheet, scale 1:3,000,000.
This publication has been superseded. Newest version available at http://www.dggs.alaska.gov/pubs/id/20181 .
Geologic map of the Katmai volcanic cluster, Katmai National Park, Alaska, 2003
Hildreth, Wes, and Fierstein, Judy, 2003, Geologic map of the Katmai volcanic cluster, Katmai National Park, Alaska: U.S. Geological Survey Miscellaneous Investigation Series Map I 2778, unpaged, 1 sheet, scale 1:63,360.
full-text PDF 23.9 MB 
Preliminary volcano-hazard assessment for the Katmai volcanic cluster, Alaska, 2001
Fierstein, Judy, and Hildreth, Wes, 2001, Preliminary volcano-hazard assessment for the Katmai volcanic cluster, Alaska: U.S. Geological Survey Open-File Report 00-0489, 50 p., 1 plate, scale not applicable.
full-text PDF 28.8 MB 
Volcanoes of Alaska, 1998
Nye, C. J., Queen, Katherine, and McCarthy, A. M., 1998, Volcanoes of Alaska: Alaska Division of Geological & Geophysical Surveys Information Circular IC 0038, unpaged, 1 sheet, scale 1:4,000,000, available at http://www.dggs.dnr.state.ak.us/pubs/pubs?reqtype=citation&ID=7043 .
Volcanoes of Alaska, 1995
Alaska Division of Geological & Geophysical Surveys, 1995, Volcanoes of Alaska: Alaska Division of Geological & Geophysical Surveys Information Circular IC 0038, unpaged, 1 sheet, scale 1:4,000,000.
Geologic map of the Mount Katmai quadrangle and adjacent parts of the Naknek and Afognak quadrangles, Alaska, 1994
Riehle, J. R., Detterman, R. L., Yount, M. E., and Miller, J. W., 1994, Geologic map of the Mount Katmai quadrangle and adjacent parts of the Naknek and Afognak quadrangles, Alaska: U.S. Geological Survey Miscellaneous Investigations Series Map I 2204, unpaged, 1 plate, scale 1:250,000.
Geothermal resources of the Aleutian Arc, 1993
Motyka, R. J., Liss, S. A., Nye, C. J., and Moorman, M. A., 1993, Geothermal resources of the Aleutian Arc: Alaska Division of Geological & Geophysical Surveys Professional Report PR 0114, 17 p., 4 sheets, scale 1:1,000,000.
Quaternary geologic map of the Mount Katmai quadrangle and adjacent parts of the Naknek and Afognak quadrangles, Alaska, 1993
Riehle, J. R., and Detterman, R. L., 1993, Quaternary geologic map of the Mount Katmai quadrangle and adjacent parts of the Naknek and Afognak quadrangles, Alaska: U.S. Geological Survey Miscellaneous Investigations Series Map I 2032, unpaged, 1 sheet, scale 1:250,000.
Holocene volcanoes of the Aleutian Arc, Alaska, 1993
March, G. D., 1993, Holocene volcanoes of the Aleutian Arc, Alaska: Alaska Division of Geological & Geophysical Surveys Public-Data File PDF 93-85, unpaged, 1 sheet, scale 1:2,000,000.
Map showing potassium-argon ages from the Mount Katmai and adjacent parts of the Naknek and Afognak quadrangles, Alaska Peninsula, Alaska, 1992
Shew, Nora, and Lanphere, M. A., 1992, Map showing potassium-argon ages from the Mount Katmai and adjacent parts of the Naknek and Afognak quadrangles, Alaska Peninsula, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF 2021-E, unpaged, 1sheet, scale 1:250,000.
Preliminary geologic map of the Mt. Katmai quadrangle and portions of the Afognak and Naknek quadrangles, Alaska, 1987
Riehle, J. R., Detterman, R. L., Yount, M. E., and Miller, J. W., 1987, Preliminary geologic map of the Mt. Katmai quadrangle and portions of the Afognak and Naknek quadrangles, Alaska: U.S. Geological Survey Open-File Report 87-0593, unpaged, 1 sheet, scale 1:250,000.
Hard Copy held by AVO at FBKS - CEC shelf
Map showing distribution, composition, and age of Late Cenozoic volcanic centers in Alaska, 1986
Luedke, R. G., and Smith, R. L., 1986, Map showing distribution, composition, and age of Late Cenozoic volcanic centers in Alaska: U.S. Geological Survey Miscellaneous Investigations Series Map I 1091-F, unpaged, 3 sheets, scale 1:1,000,000.
Eruption of Trident Volcano, Katmai National Monument, Alaska, Feb.-June 1953, 1954
Snyder, G. L., 1954, Eruption of Trident Volcano, Katmai National Monument, Alaska, Feb.-June 1953: U.S. Geological Survey Circular C 0318, 7 p., 2 sheets, scale unknown.
Hard Copy held by AVO at FBKS - CEC file cabinet
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Before an eruption
Ashfall & Preparedness Information
- Ashfall impacts & preparedness (US Geological Survey)
- Volcanic health hazards & impacts (International Volcanic Health Hazards Network)
- Ash Alert! Pamphlet (AK Division of Homeland Security & Emergency Management)
- Volcanic Ashfall (AK Department of Environmental Conservation, Division of Air Quality)
During and After an Eruption
Ash Forecasting
Mathematical models developed by the USGS forecast various aspects of how a volcanic ash plume will interact with wind—where, how high, and how fast ash particles will be transported in the atmosphere, as well as where ash will fall out and accumulate on the ground. AVO runs these models when a volcano is restless by assuming a reasonable hypothetical eruption, to provide a pre-eruptive forecast of areas likely to be affected. During an ongoing eruption, AVO will update the forecast with actual observations (eruption start time and duration, plume height) as they become available.
View the current airborne ash cloud models for Griggs
Ashfall thickness forecast
The Ash3d model was developed by the USGS to forecast how a volcanic ash plume will interact with wind and where ash will fall out and accumulate on the ground. AVO runs these models twice daily when a volcano is restless by assuming a reasonable hypothetical eruption altitude and duration. The map shows the model results of ashfall thickness for areas that are likely to be affected, if one were to occur. During an ongoing eruption, AVO will update the forecast with actual observations (eruption start time and duration, plume height) as they become available, and these plots will be automatically updated. The National Weather Service Anchorage Forecast Office will issue the official ashfall warning product and post them at weather.gov/afc
THESE PRODUCTS MAY NOT BE CURRENT.During an actual eruption, see National Weather Service forecasts of ashfall:https://weather.gov/afc.
Ashfall Forecast
Ashfall Start Time
This map shows the modeled estimate of the time it would take for ashfall to begin following an eruption. It corresponds to the ashfall thickness forecast map shown above. This map uses the start time of either the twice-daily hypothetical model runs (time shown in the legend) or the actual eruption start time (if one were to occur). In the case of an actual eruption, the National Weather Service Anchorage Forecast Office will issue the official ashfall warning product that includes the ashfall start time and post them at weather.gov/afc
THESE PRODUCTS MAY NOT BE CURRENT.During an actual eruption, see National Weather Service forecasts of ashfall:https://weather.gov/afc.