Describe the volcanic landforms associated with destructive plate margins and explain their formation.

2 parts to question: describe and explain

Volcanoes:

Formed where two plates meet and the less dense plate is forced under another in the Benioff zone - these may two oceanic plates, or continental and oceanic in which the oceanic plate is subducted. As subducted plate is destroyed, magma rises towards the surface creating the volcanic actvity.

An acid/dome volcano is formed where the lava is typically rhyolitic, meaning it has high viscosity and is very thick so does not travel far before it cools creating a steep-sided convex cone – these are evident in the Puy Region of France.

Where the lava is andesitic, slightly less viscous but still rather thick a composite cone volcano is formed which is pyramid shaped and made up of layers of lava and ash e.g. Mt Etna, Sicily.

Other volcanoes can also be found at destructive plate margins – calderas where a huge eruption has destroyed the summit of a volcano (e.g. Mt Krakatoa) and ash and cinder cones which are formed from the volcanic bombs, ash and cinders ejected from an existing volcano e.g. Paricutin, Mexico.