What happen during an earthquake?

Answer 1

Earthquakes are caused by sudden movements of the rock layers under the Earth's surface along planar structures called fault planes.

The Earth is a dynamic body and heat form the core causes convective movements in Earth's Mantle which shift around the tectonic plates forming Earth's crust. This movement progresses at about the speed your fingernails grow.

In the stiff, brittle rocks near the Earth's surface the movement does not proceed continuously ans the stresses build up and build up over time with the rocks deforming elastically until the stored energy overcomes either the strength of the rock (new fractures form) or the friction across existing fractures (fault planes).

When this happens sudden displacement occurs across the fault plane in one place (the epicentre) and this propagates along the fault plane thereafter. The movement also releases sound energy in the form sets of pressure waves which spread away form the epicentre. There are felt in other locations as a shaking of the ground - an Earthquake!

The amplitude of these determines the magnitude of the earthquake and if great can cause devastation to structures on the Earths surface.

Also if the displacement of the fault alters the topography of the seabed, the earthquake can set off a Tsunami.

Large earthquakes are usually followed by aftershocks as the movement on the first earthquake sets of instabilities across other related fault planes in the vicinity.

The largest earthquakes are usually very deep and related to the subduction of oceanic crust beneath continental crust in destructive plate boundary areas. However destructive earthquakes can also occur at shallower depths where Building are built on unconsolidated ground.

Answer 2

Deep under ground, plates rub against each other. The plates have jagged edges, and so when they rub against each other, they get stuck. Since plates constantly move, the plates that are stuck create great tension, and when they are finally free, a huge amount of energy is released. Shock waves move from focus in all directions, and it causes the earth to vibrate.

Answer 3

During an earthquake, the Earth's crust shakes due to the release of built-up tension along faults. This can result in various levels of damage to buildings, infrastructure, and the natural environment. Earthquakes can also trigger landslides, tsunamis, and aftershocks, leading to further destruction and potential hazards for those in the affected area.

Answer 4

Because the Earth isn't solid. The core of the Earth is molten rock and iron, and the crust of the Earth is shattered like the cracked shell of a hard-boiled egg.