Subduction of Oceanic Lithosphere

The lithosphere is the outer 100 km or so of the Earth. The lithosphere is broken into plates that move around the Earth's surface. Sometimes one plate goes under its neighbour and sinks into the Earth as depicted here. This process is called "subduction".

This animation shows the deformation in a slab of subducted oceanic lithosphere as it impinges on a density interface at a depth of 670 km. The slab is 80 km thick and is subducted at 8 cm/yr for a period of 12 Myr in this animation. The slab is denser than its surroundings in the upper mantle, but it deforms and buckles when it meets resistance at the 670 km interface. These images are colour coded to show the variation of strain-rate within the slab.

These calculations are made using the finite element program "basil" .

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