Divergent Plate Boundaries in the Oceans

A divergent plate boundary occurs when two tectonic plates move away from each other, either beneath the ocean or on land.

Let's focus on divergent plate boundaries in the oceans. There are convection currents in the Earth's mantle, which cause two oceanic plates to move apart gradually.

As the plates separate, magma from the mantle rises through the gap. Because of the low density of magma, it moves upward and reaches the seafloor.

When the hot magma contacts the cold ocean water, it cools and solidifies, forming new oceanic crust.

Over time, this crust accumulates, creating an underwater ridge system. As new crust forms, it pushes the older crust outward in opposite directions.

This repeated process of magma eruption and cooling creates mid-ocean ridges, which are the longest mountain ranges on the ocean. This phenomenon is called seafloor spreading.

One of the largest mid-ocean ridges is the Mid-Atlantic Ridge, which stretches across the Atlantic Ocean. In Iceland, a small section of this ridge emerges above the water and is visible on land.