Long Island
Complex in Papua New Guinea
Key Facts
Elevation
1,263 m (4,144 ft)
Type
Complex
Location
-5.314°, 147.105°
Region
Bismarck Volcanic Arc
Rock Type
Andesite / Basaltic Andesite
Tectonic Setting
Subduction zone
Location
Loading map...
Overview
The broad profile of Long Island is dominated by two steep-sided stratovolcanoes, Mount Reaumur in the north and Cerisy Peak in the south. Collapse of the basaltic-andesitic volcanic complex produced a large 10 x 12. 5 km caldera, now filled by Lake Wisdom.
Caldera formation occurred during at least three major explosive eruptions, about 16,000, 4,000, and 300 years ago. The most recent deposited andesitic tephra across the New Guinea Highlands, prompting legends of a "Time of Darkness. " Post-caldera eruptions have constructed a small cone, Motmot Island, in the south-central part of Lake Wisdom.
Moderate explosive eruptions have occurred during the 20th century from vents at and near Motmot Island.
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 | 33 years ago | Recent | Recently active |
Monitoring & Alert Status
Monitoring Networks
Current Status
Nearby Volcanoes in Southwestern Pacific Volcanic Regions
Quick Info
- •Smithsonian ID: 251050
- •Evidence: Eruption Observed
- •Epoch: Holocene
About the Photo
The broad profile of Long Island, seen here from the E, is composed of two steep-sided edifices, Mount Reaumur to the north (center) and Cerisy Peak to the south. Collapse of the volcanic complex during at least three major explosive eruptions about 16,000, 4,000, and 300 years ago produced a large 10 x 12.5 km caldera, whose low rim appears at the right.
Photo by Russel Blong, 1976 (Macquarie University).
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.