What is slab push ridge pull and convection?
In simple terms, convection is the idea that dense, cold things sink, and buoyant, warm things rise. slab pull: the force due to the weight of the cold, dense sinking tectonic plate. ridge push: the force due to the buoyancy of the hot mantle rising to the surface beneath the ridge.
What is the role of convection current for ridge push and Slab Pull?
Although ridge-push/slab-pull is the favored mechanism for plate motion, it’s important not to underestimate the role of mantle convection. Without convection, there would be no ridges to push from because upward convection brings hot buoyant rock to surface.
What is the difference between a ridge push and a Slab Pull?
‘Ridge Push’ and ‘Slab Pull’ are thought to be the major forces driving the motion of oceanic plates. Ridge push is caused by the potential energy gradient from the high topography of the ridges. Slab pull is caused by the negative buoyancy of the subducting plate.
How does ridge push and Slab Pull work?
Ridge push –magma rises as the plates move apart. The magma cools to form new plate material. Slab pull – The denser plate sinks back into the mantle under the influence of gravity. It pulls the rest of the plate along behind it.
What happens in Ridge push?
Ridge push is the result of gravitational forces acting on the young, raised oceanic lithosphere around mid-ocean ridges, causing it to slide down the similarly raised but weaker asthenosphere and push on lithospheric material farther from the ridges.
What are the effects of ridge push?
Is ridge push stronger than slab pull?
Further developments of the theory suggested that some form of ridge push helped supplement convection in order to keep the plates moving, but in the 1990s, calculations indicated that slab pull, the force that a subducted section of plate exerts on the attached crust on the surface, was an order of magnitude stronger …
Why do ridge push occur?
(the Mid-Atlantic Ridge), known as ridge push, in the Atlantic Ocean. This push is caused by gravitational force, and it exists because the ridge occurs at a higher elevation than the rest of the ocean floor. As rocks near the ridge cool, they become denser, and gravity pulls them away…
Why is ridge push important?
In plates with particularly small or young subducting slabs, ridge push may be the predominant driving force in the plate’s motion. This also causes the subducting Nazca slab to experience flat slab subduction, one of the few places in the world where this currently occurs.
How are ridge push and slab pull related to plate movement?
Explain ridge push and slab pull as a cause of plate movement. – Internet Geography Explain ridge push and slab pull as a cause of plate movement. Ridge push –magma rises as the plates move apart. The magma cools to form new plate material. As it cools It becomes denser and slides down away from the ridge.
What causes ridge push and Ridge convection in the mantle?
Mantle convection involves currents in the outer mantle carrying plates along on top. Ridge push is caused by the higher elevation new plate material at constructive plate margins pushing downwards and outwards. Slab pull is caused by old cold subducting plate sinking beneath subduction zones, pulling the rest of the plate behind it.
What happens to plates as they move away from a ridge?
Note that as the lithosphere slides down away from the ridge, tensional forces and normal fault earthquakes occur at the ridge axis where two plates are sliding (pulling) apart. “slab pull” As lithospheric plates move away from midocean ridges they cool and become denser.
What makes a plate bend at a subduction zone?
Friction between the converging plates and also the force required to bend a plate resist the movement of the plate at subduction zones. It seems likely that gravity drives the plates and the motions of the plates help to stir the mantle, rather than the convection of the mantle driving the plates.