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Churchill

Stratovolcano in United States

Last Eruption: 847

Key Facts

Elevation

5,005 m (16,421 ft)

Type

Stratovolcano

Location

61.380°, -141.750°

Region

Wrangell Volcanic Arc

Rock Type

Dacite

Tectonic Setting

Intraplate

Location

Loading map...

Overview

The Bona-Churchill massif in the St. Elias Mountains has a 2. 7 x 4.

2 km summit caldera which was the source of the White River Ash, produced by two of the largest explosive eruptions in North America during the past 2,000 years (McGimsey et al. , 1992). The summit of Mount Bona lies 4 km across a high saddle from the younger Churchill.

The source vent of the widespread bi-lobate White River Ash deposit, which covers more than 340,000 km2 of eastern Alaska and NW Canada, was initially thought to be a pumice mound that is mostly buried beneath the Klutlan Glacier NE of Churchill volcano. Later work revealed thick young pumice deposits along the caldera rim that are mineralogically and chemically similar to the White River Ash deposits.

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
Dacite
Silica Content
Varied composition

Tectonic Setting

Intraplate
Continental rift or intraplate setting with varied eruptive styles.

Age & Formation

Epoch
Holocene
Evidence
Eruption Dated

Eruption Statistics & Analysis

MetricValueGlobal RankingSignificance
Total Recorded EruptionsUnknownLowModerately active volcano
Maximum VEIVEI UnknownMinorLocal impact potential
Recent Activity1179 years agoHistoricalHistorically active

Monitoring & Alert Status

Monitoring Networks

Global Volcanism Program
International eruption database

Current Status

Normal
No recent activity. Routine monitoring continues.

Nearby Volcanoes in North America Volcanic Regions

Regional Volcanic Activity
The North America 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: 315030
  • Evidence: Eruption Dated
  • Epoch: Holocene

About the Photo

A U.S. Geological Survey climbing party ascends the Klutlan Glacier headed towards Mount Churchill. Their field studies led to the discovery that this volcano was the site of two of the most voluminous eruptions in North America in the past 2,000 years. The White River Ash originated from the summit caldera of Churchill next to Mount Bona and comprises two voluminous ash units that extend across most of Canada and traces reached Europe.

Photo by Game McGimsey (U.S. Geological Survey, Alaska Volcano Observatory).

Basic Information

This page shows basic data from the Smithsonian Global Volcanism Program. For more detailed information, visit the official Smithsonian page.