how are earthquakes formed?

Answer 1

Earthquakes arent formed. They are the effect of when a fault gets caught and when the two ends snap, it causes what we know as an earthquake. It also happens when massive amounts of magma break through the plug in a volcano, causing an eruption and a tremor or earthquake.

Answer 2

The earth's crust is made up of large plates floating on top of the liquid magma. The seams between these plates are called faults. An earthquake happens when one of these plates either slides along the one next to it, or slides up over or under the one next to it.

The plates are pushed along by convection currents in the magma underneath, but they bind together at the point where they contact another plate. When the pressure gets great enough, they break loose and slip.

The best known example of a fault is the San Andreas Fault in California. The plate on the west side of this fault is gradually moving north a few inches a year. That's why California has so many earthquakes.

The link below shows how this works

Answer 3

Most naturally occurring earthquakes are related to the tectonic nature of the Earth. Such earthquakes are called tectonic earthquakes. The Earth's lithosphere is a patchwork of plates in slow but constant motion caused by the heat in the Earth's mantle and core. Plate boundaries grind past each other, creating frictional stress. When the frictional stress exceeds a critical value, called local strength, a sudden failure occurs. The boundary of tectonic plates along which failure occurs is called the fault plane. When the failure at the fault plane results in a violent displacement of the Earth's crust, the elastic strain energy is released and seismic waves are radiated, thus causing an earthquake. This processes of strain, stress, and failure is referred to as the Elastic-rebound theory. It is estimated that only 10 percent or less of an earthquake's total energy is radiated as seismic energy. Most of the earthquake's energy is used to power the earthquake fracture growth and is converted into heat. Therefore, earthquakes lower the Earth's available potential energy, though these losses are negligible[1].

Earthquakes occurring at boundaries of tectonic plates are called interplate earthquakes, while the less frequent events that occur in the interior of the lithospheric plates are called intraplate earthquakes.

The majority of tectonic earthquakes originate at depths not exceeding a few tens of kilometers. In subduction zones, where older and colder oceanic crust descends beneath another tectonic plate, earthquakes may occur at much greater depths (up to hundreds of kilometers). These seismically active areas of subduction are known as Wadati-Benioff zones. Deep focus earthquakes are another phenomenon associated with a subducting slab. These are earthquakes that occur at a depth at which the subducted lithosphere should no longer be brittle, due to the high temperature and pressure. A possible mechanism for the generation of deep focus earthquakes is faulting caused by olivine undergoing a phase transition into a spinel structure[2].

Earthquakes may also occur in volcanic regions and are caused by the movement of magma in volcanoes. Such quakes can be an early warning of volcanic eruptions

Answer 4

Earthquakes are formed when plates beneath the earths surface move and collide

Answer 5

earthquakes usually form when earth changes its shapes. when earth changes it shape two plates that are inside the earth which are basically bringing change generates electric feild and the other generates magnetic feild so they attrach and the lower plate of electric feild comes above the magnetic feild,in short one plates come above the other and then we feel that earth quake or after shocks are coming.
it most destroys the population near to its centrral or main area from where the earth quake has been formed.
in the research it is also been seen that process of up and downs of waves of sea is been created in response of moon 's waves attraction then waves of sea comes up and shake the aerth too

Answer 6

movement of the earth's layer inside the earth..causes earthquakes.
they process of moving of earth layers is of two types folding and faulting.