What Is Earthquake ?
Release of energy waves called seismic waves in the crust of earth, leads to the creation of a natural disaster called earthquake. Earthquakes can be recorded using an instrument called as seismometer. Richter scale is used to represent magnitude and intensity of earthquakes. Those earthquakes which show reading of 3 on Richter scale are usually not harmful as such, but earthquakes which show reading of 7 or more are extremely harmful. So, more the scale of reading more harmful is the earthquake.The origin point of seismic waves is called epicenter of earthquake. If epicenter is located near the sea then it can cause the creation of Tsunami waves. Earthquakes lead to severe shaking of earth’s surface, landslides etc. Earthquakes are generally results of natural phenomena like geological stress, volcanic eruptions, landslides etc but earthquakes can also be induced by some human activities like mine blasts and nuclear experimentation etc. the first rupture point of earthquake is called focus hypocenter and epicenter is the point at ground level exactly above the hypocenter.
Naturally occurring earthquakes and earthquake storms
Those earthquakes which occur due to some natural phenomena are generally more intensified and harmful. These Tectonic earthquakes can occur just anywhere in earth where enough elastic strain energy is stored to conduct fracture propagation at a fault plane. There are basically 3 types of faults, which cause creation of the earthquakes- reverse, strike-slip and normal. Reason of a certain displacement decides the intensity of the earthquakes. Earthquakes are classified as extreme destruction source of nature because an exact warning can’t be extracted about earthquakes. Even sometimes earthquakes can hit a region in a series. In this situation one new earthquake gets triggered due to displacement, shaking or stress induction by previous strike of earthquake. This situation is called earthquake storm. This is extremely detrimental for human life and property. reference
