Theistareykir

Shield in Iceland

Last Eruption: -900

Key Facts

Elevation

563 m (1,847 ft)

Type

Shield

Location

65.883°, -16.967°

Region

Iceland Neovolcanic Rift Volcanic Province

Rock Type

Basalt / Picro-Basalt

Tectonic Setting

Rift zone

Location

Loading map...

Overview

The Holocene Theistareykir fissure system, including the basaltic Theistareykjarbunga shield volcano, extends from north of Myvatn lake to the coast of Iceland. This is the northernmost subaerial volcanic system along the Eastern Volcanic Zone of Iceland. The 30 km3 Theistareykjarbunga shield volcano formed slightly after deglaciation; the youngest dated eruption produced the Theistareykjahraun lava flow about 2,400 years ago.

Volcanic Hazards & Risk Assessment

Primary Hazards

Risk Level

Population at RiskModerate

Infrastructure RiskModerate

Aviation RiskSignificant

Geological Composition & Structure

Rock Types

Primary

Basalt / Picro-Basalt

Silica Content

Low (45-52% SiO₂)

Tectonic Setting

Rift zone

Continental rift or intraplate setting with varied eruptive styles.

Age & Formation

Epoch

Holocene

Evidence

Eruption Dated

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	2926 years ago	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 Atlantic Ocean Volcanic Regions

Regional Volcanic Activity

The Atlantic Ocean 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: 373090
•Evidence: Eruption Dated
•Epoch: Holocene

About the Photo

Stóravíti crater, seen here from the SE, is 600 m across and 140 m deep. It is located in the summit area of the Holocene Theistareykjarbunga shield volcano, part of the northernmost subaerial volcanic system along the Eastern Volcanic Zone of Iceland. The youngest dated eruption in this system produced the Theistareykjahraun lava flow about 2,400 years ago.

Photo by Michael Ryan, 1984 (U.S. Geological Survey).