World Seismicity and Earthquake Hazards

Earthquakes are caused by relative movements between tectonics plates. The stress increase up until bond friction is broken and rupture occurs realizing energy in form of waves through the earth.

The point where is originated the fault is called focus, and the point immediately upper in the ground is called epicenter. Other terms are hypocentral distance, epicentral distance.

Faults can be generated by a combination of strike-slip and dip-slip. Strike slip is a horizontal movement between plates, which could it be strike left or right. If the fault is vertical, then it is called dip-slip, which could it be reverse if that rock moves up the fault and normal if it moves downward. Thrust fault when the dip angle is shallow, usually in subduction zones.

Magnitude of Earthquakes is measured using the Richter scale.  The Richter scale measured the amplitude of the wave by means of seismograph, and corrected using a logarithmic scale. For instance, an increase in 1 degree means an increase in 10 times in energy released.

Earthquakes Hazards could it be: shaking due to ground vibrations, mudflows, liquefaction of soils, tsunamis, floods, fire.