Warning over rise in quake risk for Chile

The risk of a new earthquake may have increased in an area of Chile's Pacific coast that suffered a massive quake and tsunamis last year that killed more than 500 people.

Scientists have said the 8.8 magnitude quake on 27 February had only partly broken stresses, deep in the Earth's crust in an area south of Santiago, that have been building since an 1835 quake witnessed by British naturalist Charles Darwin.

"Increased stress may have increased the probability of another major or great earthquake in the near future," they wrote in the journal Nature Geoscience yesterday.

A "major" earthquake is between magnitude 7 and 8, causing serious damage over large areas, and a "great" quake above 8. Chile's quake was the most powerful since the 2004 quake that caused a devastating tsunami in the Indian Ocean.

"It's impossible to predict when a new quake might happen," said study leader Stefano Lorito, of Italy's Istituto Nazionale di Geofisica e Vulcanologia.