Answer
Slab pull and ridge push are two forces that contribute to plate motion in the theory of plate tectonics.
Slab pull refers to the force exerted on a tectonic plate as it subducts into the mantle beneath another plate. As the denser oceanic lithosphere sinks into the mantle, gravity acts upon it, pulling the rest of the plate along with it. This creates a dragging force that contributes to the motion of the tectonic plate.
Ridge push, on the other hand, occurs at divergent plate boundaries, such as mid-ocean ridges. Here, the lithosphere is created as magma rises and solidifies, pushing the tectonic plates apart. The newly formed lithosphere is warmer and less dense than the surrounding older lithosphere, causing it to exert a downward force due to gravity. This downward force at the ridge pushes the tectonic plates away from the ridge, contributing to plate motion.
Both slab pull and ridge push play important roles in plate motion, but the relative contribution of each force can vary depending on the specific circumstances. However, in general, slab pull is considered to be the dominant force in plate motion. The sinking of denser oceanic lithosphere at subduction zones generates a strong pulling force, which is typically greater than the pushing force exerted by ridge push. Therefore, slab pull is believed to be the primary driver of plate motion in most cases.
Work Step by Step
Slab pull and ridge push are two forces that contribute to plate motion in the theory of plate tectonics.
Slab pull refers to the force exerted on a tectonic plate as it subducts into the mantle beneath another plate. As the denser oceanic lithosphere sinks into the mantle, gravity acts upon it, pulling the rest of the plate along with it. This creates a dragging force that contributes to the motion of the tectonic plate.
Ridge push, on the other hand, occurs at divergent plate boundaries, such as mid-ocean ridges. Here, the lithosphere is created as magma rises and solidifies, pushing the tectonic plates apart. The newly formed lithosphere is warmer and less dense than the surrounding older lithosphere, causing it to exert a downward force due to gravity. This downward force at the ridge pushes the tectonic plates away from the ridge, contributing to plate motion.
Both slab pull and ridge push play important roles in plate motion, but the relative contribution of each force can vary depending on the specific circumstances. However, in general, slab pull is considered to be the dominant force in plate motion. The sinking of denser oceanic lithosphere at subduction zones generates a strong pulling force, which is typically greater than the pushing force exerted by ridge push. Therefore, slab pull is believed to be the primary driver of plate motion in most cases.
