07 October, 2011

Typhoons are recognised by the starting mechanism of slow earthquakes

In magazine Nature article that scientists have established that slow earthquakes can be started by typhoons is published.

Slow earthquakes are slow fluctuations of a terrestrial surface which some hours or some days can proceed. Seismologists studied the data about earthquakes of the 2002-2007 which have occurred in east part of Taiwan. As a result of the analysis, it was possible to establish that eleven of twenty earthquakes powerful typhoons preceded.

Within the limits of researches the mechanism of interrelation of these two processes has been defined. Taiwan settles down on a joint of the Euroasian and Philippine tectonic plates. In thickness of earth crust there is the mechanical pressure which result is earthquake. Typhoons, creating over earth crust regions the lowered atmospheric pressure, lead to pressure liberation.
As the safety valve, slow earthquakes liberate the energy which has collected in a bark, and interfere with formation of the pressure, capable to lead to catastrophic seismic consequences in magnitude eight points and above. Usually slow earthquakes have magnitude of 4-5 points and difficultly are registered, as seismographs do not notice them. To find out slow fluctuations of earth crust special gauges place in chinks depth of 200-270 metres, but such stations exist only in several regions of the world.

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