Tristan da Cunha
Shield in United Kingdom
Key Facts
Elevation
2,060 m (6,759 ft)
Type
Shield
Location
-37.092°, -12.280°
Region
Southern Atlantic Volcano Group
Rock Type
Trachybasalt / Tephrite Basanite
Tectonic Setting
Rift zone
Location
Loading map...
Overview
Tristan da Cunha is a 13-km-wide island volcano lying about 500 km E of the crest of the Mid-Atlantic Ridge just south of the latitudes of Buenos Aires and Cape Town. The shield volcano is bounded on most sides by high cliffs. Lava flows dominate both the low-angle base and the steep upper flanks, although pyroclastic cones ringing the central cone are scattered around the lower flanks.
Eruptions have occurred from the 300-m-wide summit crater, Queen Mary's Peak, which contains a small lake, and from numerous flank vents, some of which occurred from radial fissures. Radial dike swarms are prominently exposed on all sides of the island. Numerous Strombolian cinder cones occur on the flanks along both concentric ring structures and NNW- and ENE-trending radial fissures.
The only historical eruption occurred during 1961 from a north shore vent and forced the evacuation of the island's only settlement.
Volcanic Hazards & Risk Assessment
Primary Hazards
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 | 64 years ago | Historical | Recently active |
Monitoring & Alert Status
Monitoring Networks
Current Status
Nearby Volcanoes in Atlantic Ocean Volcanic Regions
Quick Info
- •Smithsonian ID: 386010
- •Evidence: Eruption Observed
- •Epoch: Holocene
About the Photo
The southwest side of Tristan da Cunha volcano rises above the southern Atlantic ocean. The summit cone Queen Mary’s Peak towers above high cliffs along most of the 12-km-wide island. Lava flows dominate both the low-angle base and the steep upper flanks, although pyroclastic cones ringing the central cone are scattered around the lower flanks. An eruption in 1961 occurred from a vent on the northern coast, just east of the island's only settlement, Edinburgh of the Seven Seas, forcing its evacuation.
Photo by Vicky Hards, 2004 (British Geological Survey, copyrighted NERC).
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.