Why and where do earthquakes happen?

How earthquakes happen?

• Do earthquakes oocur when 2 plates push against each other causing friction and than there is so much friction that it causes a explosion from the heat of the friction and the explosion causes the ground to shake (if this is true why don't scientist just measure the heat before the explosion to predict the earthquake)

• Answer:

  Most earthquakes are the result of strain which builds up in the earth due to the movement of its tectonic plates. Where plates meet, they move relative to each other. However, friction keeps the two plates from actually sliding past one another until the strain reaches a critical level, at which point the plates shift, producing the shock waves of an earthquake. Earthquakes can also occur in the middle of a plate; if the plate motion is uneven, stresses can develop within the plate and result in large-scale faulting. Volcanic activity can also cause earthquakes. The pressure caused by rising magma can fracture the rocks above it, and the movement of the magma itself also causes a specific type of earthquake called a harmonic tremor, which is an indicator that a volcanic eruption may occur soon. Shock waves can be produced in the earth even without actual earth movement. Heavy surf as well as explosions, mining, construction, and other human activities also produce measurable waves in the earth which can be recorded by seismometers. An earthquake isn't an explosion caused by heat, but temperature changes in a fault zone are one of many things being studied to see if they can be used to predict earthquakes. Unfortunately, although some earthquakes are preceded by noticeable changes, the changes don't occur consistently enough from one quake to the next to be used for predictive purposes at this time.