Types of Earthquakes
There are many diverse types of earthquakes: tectonic, volcanic, and explosion. The type of earthquake depends on the area where it occurs and the geological makeup of that region.
(i) The most common ones are the tectonic earthquakes. These are generated due to sliding of rocks along a fault plane. A tectonic earthquake is one that occurs when the earth’s crust breaks due to geological forces on rocks and adjoining plates that cause physical and chemical changes.
(ii) A special class of tectonic earthquake is sometimes recognized as a volcanic earthquake. A volcanic earthquake is an earthquake that results from tectonic forces which occur in conjunction with the volcanic activity. However, these are confined to areas of active volcanoes.
(iii) In the areas of intense mining activity, sometimes the roofs of underground mines collapse causing minor tremors. A collapse earthquake is small earthquakes in underground caverns and mines that are caused by seismic waves produced from the explosion of rock on the surface. These are called collapse earthquakes.
(iv) Ground shaking may also happen due to the explosion of chemical or nuclear devices. Such tremors are called explosion earthquakes. An explosion earthquake is an earthquake that is the result of the detonation of a nuclear and/or chemical device.
The earthquakes that happen in the areas of large reservoirs are referred to as reservoir-induced earthquakes.