As the world shrinks relative to the growth of the human population, the goal of reducing the destructive power of earthquakes becomes more and more sought-after. On the positive side, all buildings in accordance with the 1981 building code survived. Although geologist are not capable of pinpointing the time and location of an earthquake, they have made some progress in long range forecasting. In the time leading up to an earthquake, radon gas builds up in ground water as cracks form exposing decaying uranium. Seismic waves slow down as cracks form and interupt their movement.
Water soon fills the space and the waves speed up again.
As the water, a good conducter of electricity, fills these cracks, electrical resistance is decreased. By monitoring these four precursor phenomena, scientists gain data that might someday lead to advancements in the field of earthquake forecasting. Our Geologic Environment .