1. Circum-Pacific Belt: This is the largest and most active zone, often called the "Ring of Fire". It encircles the Pacific Ocean and is characterized by subduction zones where denser oceanic plates are pushed under continental plates. This process creates friction, leading to frequent earthquakes and volcanic eruptions.

2. Mediterranean-Alpine Belt: This zone stretches from the Mediterranean Sea to the Himalayas. It is associated with the collision of the African and Eurasian plates, causing mountain building and seismic activity.

3. Mid-Atlantic Ridge: This is a major underwater mountain range that runs down the center of the Atlantic Ocean. It marks a divergent plate boundary where new oceanic crust is being created. This process involves magma rising from the Earth's mantle, causing volcanic activity and earthquakes.