Istanbul prepares for major earthquake
By Jonathan Head BBC News, Istanbul
Rescue workers search for earthquake survivors in Ercis, 23 October 2011 Ercis is close to a fault-line caused by the collision of the Arabian and Eurasian tectonic plates
The precise time and place of an earthquake cannot be predicted - that is what you will hear from any seismologist charged with monitoring the grinding and shuddering of the earth's surface in geologically active regions.
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