Bogoslof
Stratovolcano in United States
Key Facts
Elevation
150 m (492 ft)
Type
Stratovolcano
Location
53.930°, -168.030°
Region
Aleutian Ridge Volcanic Arc
Rock Type
Trachyandesite / Basaltic Trachyandesite
Tectonic Setting
Subduction zone
Location
Loading map...
Overview
Bogoslof is the emergent summit of a submarine volcano that lies 40 km N of the main Aleutian arc. It rises 1,500 m above the Bering Sea floor. Repeated construction and destruction of lava domes at different locations during historical time has greatly modified the appearance of this "Jack-in-the-Box" volcano and has introduced a confusing nomenclature applied during frequent visits by exploring expeditions.
The present triangular-shaped, 0. 75 x 2 km island consists of remnants of lava domes emplaced from 1796 to 1992. Castle Rock (Old Bogoslof) is a steep-sided pinnacle that is a remnant of a spine from the 1796 eruption.
The small Fire Island (New Bogoslof), about 600 m NW of Bogoslof Island, is a remnant of a lava dome formed in 1883.
Volcanic Hazards & Risk Assessment
Primary Hazards
- Pyroclastic flows
- Lava flows
- Volcanic bombs and ballistics
- Lahars and mudflows
Risk Level
Geological Composition & Structure
Rock Types
Tectonic Setting
Age & Formation
Eruption Statistics & Analysis
| Metric | Value | Global Ranking | Significance |
|---|---|---|---|
| Total Recorded Eruptions | Unknown | Low | Moderately active volcano |
| Maximum VEI | VEI Unknown | Minor | Local impact potential |
| Recent Activity | 9 years ago | Very Recent | Currently active |
Monitoring & Alert Status
Monitoring Networks
Current Status
Nearby Volcanoes in North America Volcanic Regions
Quick Info
- •Smithsonian ID: 311300
- •Evidence: Eruption Observed
- •Epoch: Holocene
About the Photo
Bogoslof is the summit of a largely submarine volcano located in the Bering Sea, 50 km behind the main Aleutian arc. The island is about 1.5 x 0.6 km wide and due to its frequent eruptive activity and energetic wave action, has changed shape dramatically since it was first mapped in the late 1700s. The rounded lava dome and offshore spire at the northern tip of the island (bottom-center) formed in 1992. The circular, flat area at the right is a remnant of the 1927 lava dome, and the steep pinnacle is Castle Rock, a 1796 dome remnant.
Photo by Terry Keith, 1994 (Alaska Volcano Observatory, U.S. Geological Survey).
Authority Sources
Related Volcanoes
Basic Information
This page shows basic data from the Smithsonian Global Volcanism Program. For more detailed information, visit the official Smithsonian page.