Lesson 1. Plate Tectonics

• What are the main layers of the Earth?

  Lithosphere, Asthenosphere, Mesosphere
• What is the lithosphere?

  The hard outer layer of the Earth, also known as the crust
• What is the asthenosphere?

  The liquid upper mantle of the Earth
• Who first proposed the Tectonic Plate Theory?

  Alfred Wegener
• What does the Tectonic Plate Theory state about the lithosphere?

  The lithosphere is broken into hard plates that float over the molten asthenosphere
• What is one piece of evidence for the Tectonic Plate Theory?

  Continents fit together like a puzzle (Pangea)
• How do ancient fossils support the Tectonic Plate Theory?

  Fossils and rocks can be found on distant continents that were once connected
• What geological features occur at plate boundaries?

  Tsunamis, volcanoes, mountains, and ridges
• What are the two types of crust mentioned?

  Continental crust and oceanic crust
• What are hotspots in geology?

  Weak spots in the Earth's lithosphere where magma rises to the surface
• Give an example of an oceanic hotspot.

  The Hawaiian Islands
• Give an example of a continental hotspot.

  Yellowstone National Park
• What happens at convergent plate boundaries?

  Plates move towards each other, resulting in trenches and volcanoes
• What is formed at an oceanic + oceanic convergent boundary?

  Trenches and volcanoes
• What is formed at an oceanic + continental convergent boundary?

  Mountains and trenches
• What is formed at a continental + continental convergent boundary?

  Mountains and earthquakes
• What occurs at divergent plate boundaries?

  Upwelling of magma and formation of new crust
• What is an example of a divergent boundary?

  The African Rift Valley
• What happens at transform plate boundaries?

  Plates slide past each other, causing tension and earthquakes
• What is an example of a transform boundary?


  The San Andreas Fault in California
• How do earthquakes occur?

  Fault lines lock up, building stress until plates move and release energy
• What instrument measures the energy waves from earthquakes?

  Seismograph
• How is a tsunami formed?

  Underwater fault slips release energy, causing waves to form
• What happens to tsunami waves as they approach shallow water?

  Waves become larger as they reach shallow water
• Where can volcanoes be found?

  At convergent subduction zones, divergent plate boundaries, and hotspots
• What are the possible outcomes of volcanic eruptions?

  Eruptions can be mild or deadly, emitting ash and rocks
• What gases are primarily emitted by volcanoes?

  Water vapor, carbon dioxide, and sulfur dioxide
• What is one effect of ash from volcanic eruptions?

  Ash can block sunlight needed for photosynthesis
• What can sulfur dioxide cause after a volcanic eruption?

  Global cooling and climate effects
• How can volcanic eruptions affect global temperatures?

  They can decrease global temperature by 0.5-1 degrees for 1-3 years
• What are the types of plate boundaries and their characteristics?

  1. Convergent:

  • Plates move towards each other
  • Forms trenches, volcanoes, and mountains

  1. Divergent:

  • Plates move away from each other
  • Causes upwelling of magma and new crust formation

  1. Transform:

  • Plates slide past each other
  • Causes tension and earthquakes
• What are the effects of volcanic eruptions on the environment?

  • Ash can block sunlight, affecting photosynthesis
  • Sulfur dioxide can lead to global cooling
  • Eruptions can emit gases and particulates that impact climate