Geology » Plate Tectonics
View of Earth’s major lithospheric plates

The theory of plate tectonics is a unifying theory that helps explain many seeming unrelated geologic phenomena. The theory states that Earth’s lithosphere is broken into numerous slabs or plates which are in constant motion driven by heat flow from within the Earth’s interior (mantle and core). The theory of plate tectonics was first proposed in the 1960’s and was based on an earlier theory known as continental drift as well as discoveries about sea-floor bathymetry, heat flow, marine sediments, apparent polar wandering, sea-floor spreading, and magnetic anomalies.

In this lesson you will learn:

  • About the development of the theory
  • Types of plate boundaries
  • Tracking plate motion from space

Time requirement

This lesson will take about 45 minutes to complete.