How does plate tectonics relate to volcanism?

Volcanic activity is closely linked to plate tectonics, occurring predominantly along plate margins where crust is created or destroyed. At convergent boundaries, subducting plates release water into the asthenosphere, causing partial melting and generating volcanoes. Meanwhile, rifting within plates can also split continents apart and trigger localized volcanic activity.

What we know

• Most volcanic activity takes place on plate margins, and geologists agree this activity is well explained by plate tectonics. [4]
• As a cool subducting slab sinks at a convergent boundary, it heats up and releases water into the asthenosphere, leading to partial melting and volcanism. [5]
• The West Antarctic Rift System is splitting the Antarctic plate apart and is responsible for all recent volcanism in Antarctica. [2]
• Plate tectonics is driven by mantle convection cells fueled by radioactive decay heat and the return of cool surface materials. [5]

Still open

• The precise origins of volcanic activity that occurs away from plate margins remain controversial among geologists.

Where to go next

• how it workedWhat happens at convergent plate boundaries?
• what caused itWhy does intraplate volcanism happen away from plate edges?
• a case in pointHow does the Antarctic Plate move and interact with other plates?
• what followedHow is the Somali plate separating from Africa?
• the bigger pictureHow do mantle convection cells drive global tectonic movements?
• an unexpected connectionHow does a splitting continent cause volcanoes?The Antarctic continent is splitting apart along an internal rift system rather than colliding with another plate, yet this stretching still drives recent local volcanism.

Sources

• [1]Antarctic Plate (Wikidata Q501705) · CC0 1.0
• [2]Antarctic plate · CC BY-SA 4.0
• [3]Somali plate · CC BY-SA 4.0
• [4]Intraplate volcanism · CC BY-SA 4.0
• [5]Convergent boundary · CC BY-SA 4.0