What is the main cause of earthquakes?

ALTHOUGH movement of the plates (B) is responsible for 90% of global earthquakes, the other factors play a significant role as well: - Movement of tectonic plates: Most quakes happen in areas where large pieces of the Earth’s crust are meeting, sliding past one another, colliding with one another, or moving apart. - Volcanic Activity: When the position of the magma changes, it may crack rocks and alter pressure, thereby causing volcanic earthquakes and/or tremors. - Tectonic dislocation: This is a sudden break or shift in rocks, taking place on a fault line.