Convergent plate boundaries occur when tectonic plates move towards and strike one another.
As these plates move towards one another you may get Earthquakes and volcanoes and deep trenches are formed.
There are three types of convergent boundaries.
Oceanic and Continental
Oceanic and Oceanic
Continental and Continental
Oceanic/Continental
Oceanic and continental convergent boundaries occur when oceanic crust subducts beneath continental crust.
The oceanic crust has a greater density than continental crust and as it collides with the continental crust it subducts beneath the continental crust. As it sinks magma begins to rise to the surface and may form volcanic mountains. Earthquakes may also occur and deep trenches are formed
An example is The oceanic Nazca plate subducts beneath the continental South American plate. At this location, The Atacama trench has been formed in the ocean and the volcanic mountain Lascar is located on the land.
Oceanic/Oceanic
When the oceanic lithosphere collides with the oceanic lithosphere a similar event occurs. The older oceanic crust is denser than the younger crust and subducts underneath. As it subducts magma begins to rise to the surface and this creates volcanic island arcs.
An example is a portion of the North American plate covered with water subducts underneath the pacific oceanic plate. The Aleutian Islands have been created from this collision.
Continental/Continental
When continental strikes continental lithosphere neither crust subducts nor do magma or volcanoes occur. The two plates buckle and create mountains.
An example is the Indian plate colliding into the Eurasian plate and creating the Himalayan mountains.
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