Melt may trigger quakes

[thomas]

Earthquakes may be influenced by seasons.

Melting snows along Japan's mountainous backbone might trigger large earthquakes nearby, a new study shows. "It's been known for 20 years that we have more inland earthquakes in spring and summer," says geologist Kosuke Heki of the National Astronomical Observatory in Iwate, Japan. "This could be a confirmation of snow's role from a physical point of view," he says. Prevailing winds dump snow along the west-facing flanks of the mountain range running down the centre of the Japanese islands. The spring thaw lifts the weight of these vast snowdrifts - on average around one thousand kilograms per square metre - and the compressed ground rebounds. "It's just like taking a weight off a spring," says Heki.

=> http://www.nature.com/nsu/030210/030210-13.html