Balbi

Stratovolcano in Papua New Guinea

Key Facts

Elevation

2,715 m (8,907 ft)

Type

Stratovolcano

Location

-5.916°, 155.001°

Region

Bougainville Volcanic Arc

Rock Type

Andesite / Basaltic Andesite

Tectonic Setting

Subduction zone

Location

Loading map...

Overview

The complex andesitic Balbi stratovolcano on Bougainville Island includes a large number of coalesced cones and lava domes. Five well-preserved craters occupy a NW-SE-trending ridge north of the summit cone, which also contains a crater. Three large valleys with steep headwalls dissect the flanks.

The age of the most recent eruption is not known precisely. An oral tradition of a major eruption during the 19th century is thought to be in error, but could refer to minor eruptive activity. Fumaroles are located within 600-m-wide Crater B and on its W flank.

Volcanic Hazards & Risk Assessment

Primary Hazards

Pyroclastic flows
Lava flows
Volcanic bombs and ballistics
Lahars and mudflows

Risk Level

Population at RiskModerate

Infrastructure RiskModerate

Aviation RiskSignificant

Geological Composition & Structure

Rock Types

Primary

Andesite / Basaltic Andesite

Silica Content

Intermediate (57-63% SiO₂)

Tectonic Setting

Subduction zone

Formed by oceanic plate subduction, typically producing explosive eruptions due to water-rich magmas.

Age & Formation

Epoch

Holocene

Evidence

Evidence Credible

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	Unknown	Historical	Historically active

Monitoring & Alert Status

Monitoring Networks

Global Volcanism Program

International eruption database

Current Status

Normal

No recent activity. Routine monitoring continues.

Nearby Volcanoes in Southwestern Pacific Volcanic Regions

Regional Volcanic Activity

The Southwestern Pacific Volcanic Regions contains multiple active volcanic systems. Cross-regional magma interactions and tectonic stresses can influence eruption patterns across the entire arc. Monitor regional seismic activity and volcanic alerts.

Quick Info

•Smithsonian ID: 255010
•Evidence: Evidence Credible
•Epoch: Holocene

About the Photo

Balbi volcano forms the highest point on Bougainville Island and is part of a large number of coalesced cones and lava domes. Five well-preserved craters occupy a NW-SE-trending ridge N of the summit, which also has a crater. Crater C, containing a small lake, is seen here from the E. A plume from a fumarole field on the W flank of 600-m-wide Crater B is visible to the left. The latest eruption may have been as recent as the mid-19th century.

Photo by Wally Johnson, 1987 (Australia Bureau of Mineral Resources).