distribution of earthquakes

• Most earthquakes are found on plate boundaries - high concentration on the ring of fire. 
• Very few earthquakes found away from plate boundaries - intra-plate quakes. 
• Earthquakes are linked to active fault zones. 
• Attenuation is when the stored strain energy is released - transferred to kinetic and thermal energy, any energy left over is transmitted away with seismic waves. 
• Attenuation:

  As the wave travels through the rock the movement of rock particles causes friction between particles and some elastic energy is transferred to thermal energy. 

   
• Attenuation:

  High frequency waves have more oscillations per second so move more and attenuate more. Competent rocks cause the wave to lose less energy by attenuation compared to incompetent rocks.