Subduction is what type of plate boundary

At a divergent plate boundary - also known as a constructive plate boundary, the plates move apart from one another.

When this happens the magma from the mantle rises up to make or construct new crust. The movement of the plates over the mantle can cause earthquakes. Rising magma can also create shield volcanoes. Landforms at a divergent plate boundary include ocean ridges , eg the Mid-Atlantic ridge where the Eurasian plate and the North Atlantic plate are moving apart from each other under the Atlantic Ocean , rift valleys eg the East African Rift Valley and shield volcanoes.

At a conservative plate boundary , the plates slide past each other in opposite directions, or in the same direction but at different speeds. As the plates try to move, friction occurs and plates become stuck. Pressure builds up because the plates are still trying to move.

When the pressure is released, it sends out huge amounts of energy causing an earthquake. To watch a simulated fly-by along New Zealand's plate boundary check out this video. Subduction zones occur when one or both of the tectonic plates are composed of oceanic crust. The denser plate is subducted underneath the less dense plate. The plate being forced under is eventually melted and destroyed. Where oceanic crust meets ocean crust Island arcs and oceanic trenches occur when both of the plates are made of oceanic crust.

Zones of active seafloor spreading can also occur behind the island arc, known as back-arc basins. These are often associated with submarine volcanoes. Where oceanic crust meets continental crust The denser oceanic plate is subducted, often forming a mountain range on the continent. The Andes is an example of this type of collision. Where continental crust meets continental crust Both continental crusts are too light to subduct so a continent-continent collision occurs, creating especially large mountain ranges.

The most spectacular example of this is the Himalayas. The space created can also fill with new crustal material sourced from molten magma that forms below. For example, moving at about 2 inches 5 centimeters per year, in our lifetime the Pacific Plate moves 10 to 15 feet 3 - 5 meters past the North American Plate along the San Andreas Fault, a transform plate boundary in California. Plate Tectonics and Our National Parks. Divergent Plate Boundaries. Convergent Plate Boundaries. Transform Plate Boundaries.

Oceanic Hotspots. Continental Hotspots. Text and Illustrations by Robert J. Explore This Park. Types of Plate Boundaries.