What are the characteristics of divergent boundaries?
Effects that are found at a divergent boundary between oceanic plates include: a submarine mountain range such as the Mid-Atlantic Ridge; volcanic activity in the form of fissure eruptions; shallow earthquake activity; creation of new seafloor and a widening ocean basin.
Divergent boundaries in the middle of the ocean contribute to seafloor spreading. As plates made of oceanic crust pull apart, a crack in the ocean floor appears. Magma then oozes up from the mantle to fill in the space between the plates, forming a raised ridge called a mid-ocean ridge.
- Most active divergent plate boundaries occur between oceanic plates and exist as mid-oceanic ridges. Divergent boundaries also form volcanic islands which occur when the plates move apart to produce gaps which molten lava rises to fill.
- Plates move away from one another at divergent boundaries. This happens at mid-ocean ridges. Plates move towards one another at convergent boundaries; one plate is forced below another in a process called subduction. Earthquakes and composite volcanoes are common at this type of boundary.
- A mid-ocean ridge or mid-oceanic ridge is an underwater mountain range, formed by plate tectonics. This uplifting of the ocean floor occurs when convection currents rise in the mantle beneath the oceanic crust and create magma where two tectonic plates meet at a divergent boundary.
Iceland is an example of a country undergoing a continental divergent boundary. The Mid-Atlantic Ridge divides Iceland and is the boundary between the North American and Eurasian tectonic plates. When divergent boundaries occur under continental plates, they form a rift valley.
- Visit the Interactive Plate Boundary Map to explore satellite images of divergent boundaries between oceanic plates. Two locations are marked: 1) the Mid-Atlantic Ridge exposed above sea level on the island of Iceland, and 2) the Mid-Atlantic Ridge between North America and Africa.
- In plate tectonics, a divergent boundary or divergent plate boundary (also known as a constructive boundary or an extensional boundary) is a linear feature that exists between two tectonic plates that are moving away from each other.
- At convergent plate boundaries, where two continental plates collide earthquakes are deep and also very powerful. In general, the deepest and the most powerful earthquakes occur at plate collision (or subduction) zones at convergent plate boundaries.
Updated: 12th November 2019