How does mantle convection drive plate tectonics?

Mantle convection is the slow creeping motion of Earth's solid silicate mantle, driven by internal heat from radiogenic decay and primordial formation. This convective movement directly causes tectonic plates to form, move, and be consumed at plate boundaries. Specifically, sinking dense oceanic crust at subduction zones acts as the strongest downward driver of plate motion, while seafloor spreading adds new crust at divergent margins.

What we know

• Mantle convection is the very slow creep of Earth's solid silicate mantle caused by convection currents carrying heat from the interior to the surface. [1, 2]
• Earth's internal heat budget, driven by radiogenic and primordial heat sources, powers mantle convection and plate tectonics. [3]
• At subduction zones, cold and dense oceanic crust sinks down into the mantle, forming the downward convecting limb which serves as the strongest driver of plate motion. [4]
• Tectonic plates float across the ductile asthenosphere, where lateral density variations in the mantle result in ongoing convection currents. [4]

Still open

• The relative importance and interaction of specific factors like active convection, upwelling inside the mantle, and tidal drag of the Moon remain subjects of debate.
• Some subducted material reaches the lower mantle while other material is impeded from sinking further, possibly due to an endothermic phase transition.

Where to go next

• what caused itWhat powers Earth's internal heat budget?
• how it workedHow do subduction zones work?
• a case in pointWhat are large low-shear-velocity provinces?
• what followedHow does plate tectonics shape Earth's crust?
• the bigger pictureWhat is Earth's internal heat budget?
• an unexpected connectionHow are deep mantle superplumes named after plate tectonics pioneers?The two main large low-shear-velocity provinces in the lower mantle are named Tuzo and Jason after geologists Tuzo Wilson and W. Jason Morgan, linking deep mantle structures directly to foundational figures of plate tectonics.

Sources

• [1]mantle convection (Wikidata Q120005) · CC0 1.0
• [2]Mantle convection · CC BY-SA 4.0
• [3]Earth's internal heat budget · CC BY-SA 4.0
• [4]Plate tectonics · CC BY-SA 4.0
• [5]Large low-shear-velocity provinces · CC BY-SA 4.0

Your path

1. What is vernacular architecture?
2. /What is Levantine archaeology?
3. /How does mantle convection drive plate tectonics?