They are among the most powerful natural disasters that can strike mankind. Earthquakes come out of the blue, completely unexpectedly and with tremendous destructive power.
By Tobias Aufmkolk and Hilmar Liebsch
The continents move
The earth shakes several hundred times every day. Such quakes are evidence of the enormous forces that prevail inside our planet. But why does the earth shake at all?
Earthquakes have always been scary to people. The ground under your feet starts to shake, cracks open up and houses fall down. For thousands of years, the wrath of the gods was blamed for them. Also many natural scientists of the modern times invented partly quite absurd seeming theories, how earthquakes could originate.
It was not until the beginning of the 20. At the beginning of the twentieth century, the solution came a decisive step closer. In 1912, German geoscientist Alfred Wegener theorized that individual continents are not firmly anchored to the Earth’s crust but are moving.
At the beginning Wegener was smiled at by his colleagues. But he laid with his considerations the foundation-stone for the theory of the plate tectonics, which was developed further only in the 1960er years crucially.
Earthquakes can also occur when two continental plates collide head on. Plates are shifting rock masses in these regions and uplifting mountains. Most earthquakes in India and China are due to the collision of two continental plates.