March 14, 2013. System earthquake early warning is being tested in California, Pasadena.
This is a test program that will use thousands of sensors that warn people of impending shocks. Last scientists at Caltech managed prevent earthquake magnitude 4.7 points in Anza.
Before the earthquake, even a few seconds can affect the outcome of further rescue, seismologists said.
Such a program has been used in Japan since 2007. Thanks to this development were warned about 50 million inhabitants before the Fukushima earthquake in 2011.
Warning Scientists carried out in two stages: the station near the epicenter inform researchers about the first signal, which is a P-wave, then triggered multiple sensors that absorb vibration.
One station notifies the faster but less reliable than the second, which takes more time to warn seismologists, but gives more accurate information.
However, this warning systems have a significant negative
The tremors are moving along the ground at a speed of sound, or about eight kilometers per second. Therefore system will not have time to report on the earthquake, which are located within a radius of 20 kilometers from the epicenter, the area was called "blind spots" because of its proximity to the source.