Divergent Plate Boundaries

Question 1

What are divergent plate boundaries (oceanic)

Answer 1

A new crust is formed at these boundaries e.g. Mid ocean ridges. This is also called sea-floor. spreading This happens when 2 plates pull apart. The movement is caused by convection currents in the asthenosphere flowing away from each other. The American and Eurasian plate began to pull apart from each other 100 million. As the plates continued to pull apart, molten magma rose up to fill the gap and hardened to form new crust at this boundary. This is the Mid Atlantic Ridge a long chain of active volcanoes beneath the Atlantic Ocean. The Atlantic Ocean is widening at approx 3cm a year.

Question 2

What are divergent plate boundaries (continental)

Answer 2

A continental plate can sometimes split and the two halves are pulled apart by convection currents, e.g. African Plate. The crust can be stretched, weakened and finally fractures (cracks) along fault lines. The land between the fault lines sinks to form a rift valley. Example: the African continent is being pulled apart along the East African Rift Valley.