Our planet is made up of core at its centre that is then followed by mantle and finally the crust, which is the land that we see. The land has its foundations in the tectonic plates that are constantly in motion. However, when these tectonic plates get stuck or encounter some friction, we feel an impact on the land which is called an earthquake. It is the slip or fault felt by these tectonic plates that causes massive destruction or even tsunamis on the surface of the earth.
What is a tectonic plate and how does their movement cause earthquakes?
A lithospheric surface of our planet Earth makes the tectonic plate. These plates are massive, irregularly shaped slab of solid rock, and are made up of both continental and oceanic lithosphere.
These tectonic plates are constantly moving slowly, but they do get stuck at their edges due to friction. When the stress on the edge overcomes the friction, it results in an earthquake. Such a reaction releases energy in the form of waves that travel through the Earth's crust. This ultimately results in the shaking of the surface, as we feel it. These waves are also called seismic waves as they are generated by an earthquake, explosion, or similar source of equal magnitude and propagated within the Earth or along its surface.
What does an earthquake generate?
Earthquakes generate four main types of elastic waves. Two of them are known as body waves that travel within the Earth, whereas the other two are called surface waves that travel along its surface. The amplitude and frequency of seismic waves is recorded by an instrument known as seismographs. These instruments record and present information about the Earth and its subsurface structure.
Minor earthquakes are also created through man-made activities when data on oil and gas is being collected. It is through artificially generated seismic waves recorded during seismic surveys that some fossil fuel industries find data on natural gas and coal.
Natural earthquakes usually occur most often along geologic faults, which are planar or gently curved fractures in the rocks of Earth’s crust. They result in places where compressional or tension related forces cause relative displacement of these plates on the opposite sides of the fracture. The major fault lines of the world are located at the edges of these huge tectonic plates that make up Earth’s crust.