Earthquake monitoring technique

Edinburgh University scientists have developed a seismic interferometry technique to monitor movements beneath the Earth’s surface.

The new method, which uses data collected from earthquakes, could potentially allow the Earth’s seismic activity to be mapped more comprehensively.

When an earthquake occurs within the Earth, waves are sent out in all directions. These eventually come to the surface where they are recorded by seismometers. The recordings provide an indication of how the earthquake 'sounded' once the sound propagates to the surface of the Earth.

Now, Prof Andrew Curtis at Edinburgh University has shown that by using the knowledge gained about how energy from a first earthquake travels from its epicentre to the surface, it is possible to 'back-project' the recordings of a second earthquake from the surface down to the location of the first.

The result is a calculation of how the second earthquake would have 'sounded' at the location of the first, turning the first earthquake into a virtual seismometer.