Earthquakes or earthquakes are more common than you might imagine , appearing frequently in some specific areas of the planet such as Japan , Indonesia and Chile and, to a lesser extent, in Peru, the United States, Mexico or Iran.
But how does an earthquake originate?
The tectonic plates of which the earth’s crust is formed are in continuous movement , but this is usually slow and imperceptible. However, when something obstructs this movement and they collide with each other, a large amount of energy begins to accumulate which is suddenly released when there is a sudden movement of these plates. This energy emerges on the earth’s surface in what we know as an earthquake. Earthquakes occur when energy is released when these plates slide past each other.
This type of earthquake, called tectonic , covers the vast majority of earthquakes that exist. The other less common type of earthquake is volcanic , which is produced by volcanic action due to the expansive force of gases and vapors that produce explosions when magma rises up the volcano’s chimney.
The ground moves
Despite appearancesthe ground beneath our feet is constantly in motion.Underneath is the mantle, which consists of a hot molten rock. Movement within the mantle is governed byconvection,which makes it comparable to the operation of a huge lava lamp. The hottest rock near the planet’s core is less dense and moves upward toward the surface. As the rock cools, it thickens and sinks.
These currents act like giant conveyor belts, pushing plate tectonics slowly but surely up to 10 cm per year.Although it may seem surprising, it is almost as fast as nails grow. When tectonic plates move against each other, friction sometimes causes two plates to jam when their ragged edges catch. When this happens, pressure builds, until eventually the rock gives way and the plates suddenly slide past each other.The stored energy is released abruptly and the vibrations travel in shock waves through the rock.
These seismic waves radiate in all directions from the underground point where the energy was released, known as the focus. Directly above it is the epicenter of the earthquake: the point on the earth’s surface where the earthquake will be most strongly experienced.
The result can be anything from an imperceptible shaking to a complete earthquake, depending on the amount of energy liberada.
Almost all earthquakes are confined to plate tectonic boundaries, butpredicting individual earthquakes is still nearly impossible. Fortunately, of the hundreds of thousands of earthquakes that occur each year, most are so weak that we don’t even notice them.
Effects of earthquakes
An earthquake damages buildings and land, causes tsunamis, and has many other disastrous effects. The violent shaking of an earthquake collapses buildings, causing the majority of deaths and casualties, destroys power lines and breaks natural gas supply lines, causing fires. The ground can also collapse or separate , causing more buildings to fall. Tsunamis occur after an earthquake on the ocean floor. The water shock wave travels through the ocean until it dissipates or meets the land. If the wave meets land, the water accumulates, creating a single wave or series of huge waves that sweep inland, causing death and destruction.
