Keywords

• earthquake


  shocks or tremors in a part of the Earth's crust caused by endogenic forces
• Richter scale


  scale for measuring the strength of an earthquake
• epicentre


  the point where an earthquake breaks through the Earth's surface, directly above the hypocentre
• tsunami


  huge tidal wave caused by a seaquake that floods coastal areas
• aftershock


  smaller earthquake that occurs in the same place hours, days or even weeks after the main earthquake
• fault


  crack or fracture in the Earth's crust
• convergence


  when tectonic plates move towards each other
• oceanic plate


  tectonic plate that is at the bottom of the ocean
• continental plate


  tectonic plate that contains large land masses
• subduction


  when an oceanic plate slides underneath a continental plate
• strike-slip fault


  fault where 2 rock masses slide past one another horizontally
• reverse fault


  fault that occurs when a mass of rock breaks into 2 pieces and one piece is thrust upward
• normal fault


  fault that occurs when a mass of rock breaks into 2 pieces and one piece moves downward
• seismic gap


  area along an active fault where there has been little or no earthquake activity compared to other areas along the same fault
• magma

  hot, liquid rock inside the earth
• fold mountain range


  mountain range formed when the collision of tectonic plates creates folds in parts of the Earth's crust
• block mountain range


  mountain range formed in a region with many fault zones
• trench


  long, deep, narrow depression in the oceanic floor caused by the subduction of an oceanic plate
• divergence


  when tectonic plates move away from eachother
• hypocentre


  place deep in the earth's surface where an earthquake begins
• relief 


  differences in elevation in a landscape
• transform movement


  when tectonic plates slide past one another