Built a vast Network of Radon-Thoron helps us predict earthquakes better

In 2011,just before an earthquake struck the east coast of Japan,nearby researchers recorded surprisingly high concentrations of the radioactive isotope pair: radon and thoron.As stress builds up in the crust right before an earthquake,microfractures allow these gases to escape to the surface.These scientists think that if we built a vast network of radon-thoron detectors in earthquake-prone areas,it could become a promising warning system–potentially predicting quakes a week in advance.