The continuous movement of the Earth's surface does not occur without traumas for our planet. The direct result of the Earth's inner vitality is the most dangerous catastrophe for Man: the earthquake. But, just how does an earthquake start? The thrusts that force various parts of the land surface to move in a certain direction generally do not cause an immediate shift: there are areas where these forces are gradually accumulating. Slowly, the rocks rise and bend, until suddenly, they break and shift. The result is a seismic jolt that is sometimes destructive, and at other times, so insignificant that it can only be perceived by the most sensitive seismograph. The first true seismographs appeared only at the beginning of this century. However, since that time, very effective methods have been developed to determine where a specific earthquake has occured on the Earth's surface. The first earthquake distribution charts clearly show that earthquakes are very frequent in certain areas of the Earth and very rare in others. Indeed, earthquakes are exclusively concentrated in long, narrow areas that divide regions where earthquakes are uncommon. Now we know why: they are concentrated exactly along the edges of the large, moving plates of the Earth's surface where they collide, move away from, and slide against each other.
The continuous movement of the Earth's surface does not occur without traumas for our planet. The direct result of the Earth's inner vitality is the most dangerous catastrophe for Man: the earthquake. But, just how does an earthquake start? The thrusts that force various parts of the land surface to move in a certain direction generally do not cause an immediate shift: there are areas where these forces are gradually accumulating. Slowly, the rocks rise and bend, until suddenly, they break and shift. The result is a seismic jolt that is sometimes destructive, and at other times, so insignificant that it can only be perceived by the most sensitive seismograph. The first true seismographs appeared only at the beginning of this century. However, since that time, very effective methods have been developed to determine where a specific earthquake has occured on the Earth's surface. The first earthquake distribution charts clearly show that earthquakes are very frequent in certain areas of the Earth and very rare in others. Indeed, earthquakes are exclusively concentrated in long, narrow areas that divide regions where earthquakes are uncommon. Now we know why: they are concentrated exactly along the edges of the large, moving plates of the Earth's surface where they collide, move away from, and slide against each other.
