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  • United States
  • Alaska
  • Stratovolcano
  • 1814 CE
  • Country
  • Volcanic Region
  • Primary Volcano Type
  • Last Known Eruption
  • 57.751°N
  • 156.368°W

  • 1474 m
    4835 ft

  • 312130
  • Latitude
  • Longitude

  • Summit

  • Volcano

The Global Volcanism Program has no activity reports for Ugashik-Peulik.

The Global Volcanism Program has no Weekly Reports available for Ugashik-Peulik.

The Global Volcanism Program has no Bulletin Reports available for Ugashik-Peulik.

Basic Data

Volcano Number

Last Known Eruption



1814 CE

1474 m / 4835 ft


Volcano Types

Lava dome(s)

Rock Types

Andesite / Basaltic Andesite
Basalt / Picro-Basalt

Tectonic Setting

Subduction zone
Continental crust (> 25 km)


Within 5 km
Within 10 km
Within 30 km
Within 100 km

Geological Summary

The Ugashik-Peulik volcanic complex lies south of Becharof Lake and east of Upper Ugashik Lake. Late-Pleistocene caldera formation at Ugashik volcano was followed by the emplacement of at least 5 Holocene lava domes within the 4.5-km-wide caldera. Most of the caldera walls consist of basement sandstones of Jurassic age. Following caldera formation the small, 3 cu km Peulik stratovolcano grew 2.5 km to the north to a height of 1474 m, more than 500 m above that of Ugashik. Lava flows from Peulik cover the caldera rim to the south and extend to Becharof Lake, 6 km to the north. A small lava dome at 1200 m elevation on the east flank of Peulik was the source of a small block-and-ash flow. The summit of Peulik volcano contains a 1.5-km-wide crater breached to the west that is partially filled by a lava dome. Debris-avalanche deposits cover a 75 sq km area to the NW. A single documented historical eruption took place from Peulik volcano in 1814.


The following references have all been used during the compilation of data for this volcano, it is not a comprehensive bibliography.

Coats R R, 1950. Volcanic activity in the Aleutian Arc. U S Geol Surv Bull, 974-B: 35-47.

Detterman R L, Wilson F H, Yount M E, Miller T P, 1987. Quaternary geologic map of the Ugashik, Bristol Bay, and western part of Karluk quadrangles, Alaska. U S Geol Surv Map, I-1801.

Fierstein J, 2007. Explosive eruptive record in the Katmai region, Alaska Peninsula: an overview. Bull Volc, 69: 469-509.

IAVCEI, 1973-80. Post-Miocene Volcanoes of the World. IAVCEI Data Sheets, Rome: Internatl Assoc Volc Chemistry Earth's Interior..

Kienle J, Swanson S E, 1983. Volcanism in the eastern Aleutian Arc: late Quaternary and Holocene centers, tectonic setting and petrology. J Volc Geotherm Res, 17: 393-432.

Miller T P, 1984. Two-stage volcanism at the Ugashik-Peulik volcanic center, Alaska Peninsula. Geol Soc Amer Abs Prog, 16: 322.

Miller T P, 2004. Geology of the Ugashik-Mount Peulik volcanic center, Alaska. U S Geol Surve Open-File Rpt, 2004-1009: 1-19.

Miller T P, McGimsey R G, Richter D H, Riehle J R, Nye C J, Yount M E, Dumoulin J A, 1998. Catalogue of the historically active volcanoes of Alaska. U S Geol Surv Open-File Rpt, 98-582: 1-104.

Motyka R J, Liss S A, Nye C J, Moorman M A, 1993. Geothermal resources of the Aleutian arc. Alaska Div Geol Geophys Surv, Prof Rpt, no 114, 17 p and 4 map sheets.

Smith R L, Shaw H R, Luedke R G, Russell S L, 1978. Comprehensive tables giving physical data and thermal energy estimates for young igneous systems of the United States. U S Geol Surv Open-File Rpt, 78-925: 1-25.

Smith W R, Baker A A, 1922. The Cold Bay-Chignik district, Alaska. U S Geol Surv Bull, 755-D: 156-157 & 191-192.

Wood C A, Kienle J (eds), 1990. Volcanoes of North America. Cambridge, England: Cambridge Univ Press, 354 p.

Eruptive History

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

Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
[ 1852 ] [ Unknown ] Uncertain     Peulik
1814 Unknown Confirmed 3 Historical Observations Peulik
1050 ± 100 years Unknown Confirmed   Radiocarbon (uncorrected) Peulik
5850 BCE (?) Unknown Confirmed   Radiocarbon (uncorrected) Peulik
6550 BCE (?) Unknown Confirmed   Radiocarbon (uncorrected) Peulik

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.


Puyulek | Bocharova (?) | Smoky Mountain


Feature Name Feature Type Elevation Latitude Longitude
Peulik Stratovolcano 1474 m 57° 45' 3" N 156° 22' 5" W


Feature Name Feature Type Elevation Latitude Longitude
Ugashik Pleistocene caldera 914 m 57° 43' 43" N 156° 22' 10" W

Photo Gallery

Mount Peulik is a 1474-m stratovolcano that was constructed immediately north of Ugashik caldera. It is seen here from NW near Ukinrek Maars. The hummocky terrain in the middle distance is a debris-avalanche deposit produced by collapse of ancestral Peulik volcano. Only one historical eruption, in 1814, is known from Peulik.

Photo by Christina Neal, 1993 (Alaska Volcano Observatory, U.S. Geological Survey).
The 4.5-km-wide Ugashik caldera was formed during the late Pleistocene. Five unglaciated Holocene lava domes occupy the caldera, seen here from the east with Upper Ugashik Lake in the background. The small Peulik stratovolcano was constructed immediately north of the caldera, out of view to the right, and partially overtops the caldera rim. Puelik has a summit crater that is breached to the west and contains a dacitic lava dome.

Photo by Betsy Yount (Alaska Volcano Observatory, U.S. Geological Survey).

Smithsonian Sample Collections Database

The following 5 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 117233-100 Dacite
NMNH 117233-101 Dacite
NMNH 117233-102 Basalt
NMNH 117233-103 Basalt
NMNH 117233-99 Dacite

Affiliated Sites

Large Eruptions of Ugashik-Peulik Information about large Quaternary eruptions (VEI >= 4) is cataloged in the Large Magnitude Explosive Volcanic Eruptions (LaMEVE) database of the Volcano Global Risk Identification and Analysis Project (VOGRIPA).
WOVOdat WOVOdat is a database of volcanic unrest; instrumentally and visually recorded changes in seismicity, ground deformation, gas emission, and other parameters from their normal baselines. It is sponsored by the World Organization of Volcano Observatories (WOVO) and presently hosted at the Earth Observatory of Singapore.
EarthChem EarthChem develops and maintains databases, software, and services that support the preservation, discovery, access and analysis of geochemical data, and facilitate their integration with the broad array of other available earth science parameters. EarthChem is operated by a joint team of disciplinary scientists, data scientists, data managers and information technology developers who are part of the NSF-funded data facility Integrated Earth Data Applications (IEDA). IEDA is a collaborative effort of EarthChem and the Marine Geoscience Data System (MGDS).
MODVOLC - HIGP MODIS Thermal Alert System Using infrared satellite Moderate Resolution Imaging Spectroradiometer (MODIS) data, scientists at the Hawai'i Institute of Geophysics and Planetology, University of Hawai'i, developed an automated system called MODVOLC to map thermal hot-spots in near real time. For each MODIS image, the algorithm automatically scans each 1 km pixel within it to check for high-temperature hot-spots. When one is found the date, time, location, and intensity are recorded. MODIS looks at every square km of the Earth every 48 hours, once during the day and once during the night, and the presence of two MODIS sensors in space allows at least four hot-spot observations every two days. Each day updated global maps are compiled to display the locations of all hot spots detected in the previous 24 hours. There is a drop-down list with volcano names which allow users to 'zoom-in' and examine the distribution of hot-spots at a variety of spatial scales.
MIROVA Middle InfraRed Observation of Volcanic Activity (MIROVA) is a near real time volcanic hot-spot detection system based on the analysis of MODIS (Moderate Resolution Imaging Spectroradiometer) data. In particular, MIROVA uses the Middle InfraRed Radiation (MIR), measured over target volcanoes, in order to detect, locate and measure the heat radiation sourced from volcanic activity.