Lesson 2

• What is the theory that explains the movement of the Earth's crustal plates?

  Plate Tectonics
• How were the present-day continents formed according to the study material?


  They came from a single large mass that has been broken down into pieces.
• What are the two main types of forces that influence the movement of tectonic plates?

  Driving forces and resisting forces.
• What is the average speed at which tectonic plates move?

  About 2.5 cm per year.
• What are the different types of driving forces mentioned in the study material?

  Mantle convection, slab pull, slab suction, and ridge push.
• What happens during slab/trench suction?

  Convection currents in the upper mantle suck both plates down when two plates collide, with one subducting underneath the other.
• What is slab resistance in the context of plate tectonics?

  It is the force that resists subduction when a heavy plate is pulled into the mantle due to friction.
• What is collisional resistance?


  It is the frictional force due to the opposing movement of plates moving past one another between two spreading centers.
• What is transform fault resistance?


  It is a type of resisting force that occurs along transform faults where plates slide past each other.
• What are the three types of resisting forces mentioned in the study material?

  Slab resistance, collisional resistance, and transform fault resistance.
• What is the significance of the question about continents converging into a single landmass after 250 million years?


  It prompts consideration of the long-term effects of plate tectonics on continental formation.
• How do we describe and relate the distribution of active volcanoes, earthquake epicenters, and major mountain belts to Plate Tectonic Theory?

  • Active volcanoes are often found at plate boundaries.
  • Earthquake epicenters are concentrated along fault lines.
  • Major mountain belts form where tectonic plates collide.
• What is the role of mantle convection in plate tectonics?

  It is one of the driving forces that influence the movement of tectonic plates.
• What is ridge push in the context of plate tectonics?

  It is a driving force that occurs at mid-ocean ridges where new crust is formed.
• What is drag force in relation to plate movements?

  It is a force that opposes the motion of tectonic plates.