The Glacial Earthquakes of Greenland
Seismometers around the world kept picking up slow, rumbling earthquakes from Greenland, where there should be none. They were coming from the ice.
What was reported
In 2003, seismologists studying global earthquake records found dozens of unusual events coming from Greenland, a place with very little earthquake activity. They were slow, lasting up to a minute, and had gone unnoticed because standard detection methods missed them.
The events were concentrated at the mouths of Greenland's great glaciers, and they became more frequent over the years.
Explanations offered
Researchers found that the quakes happen when glaciers calve huge icebergs into the sea. As a vast block of ice capsizes, it pushes the glacier backwards and shakes the ground. Their increase is linked to faster-moving glaciers as the climate warms.
- When
- Discovered in 2003
- Where
- Helheim Glacier, east Greenland
- Witnesses
- Seismometers worldwide
- Status
- Explained
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