Question

Why does density play a key role in subduction?

Answer 1

Answer and explanation;

• Density plays an important role in the study of Earth. It affects Earth's climate, plate tectonics, and subduction.
• Subduction occurs at the convergent plate boundaries. Density plays a major role for subduction to take place. Subduction is driven by the excess density of the lithosphere compared to the underlying asthenosphere.
• Oceanic plates are denser and colder than continental plates, because the ocean cools them. Subduction can occur between an oceanic plate and a continental plate, or two oceanic plate or two continenetal plates.
• During subduction between oceanic and continental plates, mantle convection drags the denser oceanic plate downwards and forces it down into the asthenosphere.
• During subduction between two oceanic plates, mantle convection drags the older, denser oceanic plate downwards and forces it into the asthenosphere.
• During subduction between two continental plates, there is no mantle convection, because the two plates are of similar densities.