Divergent Plate Boundaries
Divergent Plate Boundary Continental Crust was once whole Over time the crust started spreading apart to create a Rift Valley. Ocean fills in The Ocean floor keeps spreading open
Divergent Plate Boundaries As plates move away from the ridge, the gaps are filled with molten rock that oozes up from the hot mantle. This adds new crust between the diverging plates.
Iceland is located on the Mid-Atlantic Ridge
Eyjafjallajokull volcano, Iceland The volcano had been dormant for 200 years. Before 2010
Eyjafjallajokull volcano, Iceland After 2010
Divergent Convergent Transform
Three types of convergent boundaries: Oceanic - Continental Oceanic - Oceanic Continental - Continental
Oceanic - Continental The plate which descends into the Mantle melts and turns into magma. This magma then rises back up to the surface.
The volcanic Andes Mountains were formed by oceanic-continental convergence, when the Nazca plate melted as it plunged beneath the continent of South America.
The Cascade Mountain Range, in western U. S. , is a volcanic mountain range that was formed as a result of oceanic-continental convergence. Eruption of Mount St. Helens in 1980
Oceanic – Continental Oceanic - Oceanic Continental - Continental
Oceanic - Oceanic Convergence When two oceanic plates converge, one subducts or descends beneath the other initiating volcanic activity (similar to the oceanic continental case), but the volcanoes form on the ocean floor rather than on continents.
Examples of island arcs are the island chains of the western Pacific Ocean, such as Japan. In the case of Japan, volcanic islands are being created by the collision of the Pacific plate with the Eurasian plate. The Pacific plate being subducted beneath the Eurasian plate.
Oceanic – Continental Forms Volcanic Arcs Oceanic – Oceanic Volcanoes form on the Ocean floor Continental – Continental Mountains form
Continental - Continental Convergence Mountains form from the collision of 2 continental plates.
India Colliding with Asia
Hot Spots Volcanoes not formed at Plate Boundaries
Hawaii- Hot Spot
World-Wide Hot Spot