* Earth's Structure: The Earth's outer layer, the lithosphere, is broken into large pieces called tectonic plates. These plates constantly move, interacting with each other at their boundaries.
* Stress and Strain: The movement of plates creates immense stress and strain along their edges. This stress builds up over time until it exceeds the strength of the rocks, causing them to suddenly break or slip.
* Types of Plate Boundaries:
* Convergent Boundaries: Plates collide. This can cause subduction (one plate slides beneath another) or continental collision (two continents crash together). Earthquakes are common at these boundaries, especially along subduction zones.
* Divergent Boundaries: Plates move apart. This creates new crust and often results in volcanic activity, as well as shallow, less powerful earthquakes.
* Transform Boundaries: Plates slide past each other horizontally. These boundaries are known for their powerful and destructive earthquakes, like the San Andreas Fault in California.
In summary:
* Plate boundaries are zones of intense geological activity.
* The movement of tectonic plates creates stress and strain that eventually leads to earthquakes.
* The type of plate boundary determines the characteristics of the earthquakes that occur there (depth, magnitude, frequency).
Important Note: While most earthquakes occur at plate boundaries, some can also occur within plates, called intraplate earthquakes. These are less common but can still be significant.
