Slab Pull: The force exerted by the weight of the subducted slab on the plate it is attached to. Ridge Push: The pressure exerted by the excess height of the mid-ocean ridge.
What is slab pull theory?
What is Slab Pull? Slab pull is the pulling force exerted by a cold, dense oceanic plate plunging into the mantle due to its own weight. The theory is that because the oceanic plate is denser than the hotter mantle beneath it, this contrast in density causes the plate to sink into the mantle.
What is slab pull quizlet?
Slab pull. The process that results when a dense oceanic plate sinks beneath a more buoyant plate along a subduction zone, pulling the rest of the plate that trails behind it. convection.
What is slab pull a level geography?
Slab pull occurs where older, denser tectonic plates sink into the mantle at subduction zones. As these older sections of plates sink, newer and less dense sections of plate are pulled along behind. Sinking in one place leads to plates moving apart in other places.
Is slab pull a form of convection?
The motion of tectonic plates is driven by convection in the mantle. … There are three main forces that determine the rate at which tectonic plates move as part of the mantle convection system: slab pull: the force due to the weight of the cold, dense sinking tectonic plate.
What is ridge push theory?
Ridge push (also known as gravitational sliding) or sliding plate force is a proposed driving force for plate motion in plate tectonics that occurs at mid-ocean ridges as the result of the rigid lithosphere sliding down the hot, raised asthenosphere below mid-ocean ridges.
What affects slab pull?
What is the effect of slab pull? The effect of slab pull is a force generated by denser oceanic plate subducting under a continental plate, and gravitationally being pulled into the upper mantle. The gravitational force generated by slab pull pulls the rest of the oceanic plate along with it.
What is the difference between Ridge pull and slab pull?
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.
Is slab pull a result of mantle convection?
The ridge push / slab pull model also relies on mantle convection, but in this case it is not simply the traction from the convection cell that moves the plates.
Which of the following are characteristics of Slab Pull?
The following are characteristics of slab pull: Subducting plates move faster than non-subducting plates. Gravity is a major force in slab pull. Subducting oceanic lithosphere is denser than asthenosphere.
Which of the following sentences best describes Slab Pull?
Which of the following sentences best describes slab pull? Cold oceanic lithosphere is pulled down into the mantle by gravity.
What is ridge push and Slab Pull quizlet?
ridge-push. a mechanism that may contribute to plate motion; it involves the oceanic lithosphere sliding down the oceanic ridge under the pull of gravity. slab-pull. a mechanism that contributes to plate motion in which cool, dense oceanic crust sinks into the mantle and “pulls” the trailing lithosphere along.
How does slab pull cause tectonic plates to move?
One explanation for plate movements is slab pull. Plates are extremely heavy so gravity acts upon them, pulling them apart. Alternatively, as shown in the diagram, convection currents under the Earth’s crust transfer heat, which rises through the surface and cools back down in a circular motion.
Is the continental drift?
Continental drift is the hypothesis that the Earth’s continents have moved over geologic time relative to each other, thus appearing to have “drifted” across the ocean bed. … The speculation that continents might have ‘drifted’ was first put forward by Abraham Ortelius in 1596.
What causes ridge pull?
plate tectonics
(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…
What causes convection?
Convection currents are the result of differential heating. Lighter (less dense), warm material rises while heavier (more dense) cool material sinks. It is this movement that creates circulation patterns known as convection currents in the atmosphere, in water, and in the mantle of Earth.
What is a slab pull apex?
Slab Pull. Slab Pull. As a crustal plate moves further from an oceanic ridge, it cools and becomes increasingly dense. This causes it to sink beneath the continental crust in a subduction zone.
What is trench suction?
Trench Suction is thought to result from small-scale convection in the mantle wedge, driven by the subducting lithosphere. This force is difficult to isolate from other forces because of how little we know about mantle convection in the shallow subsurface (Ziegler, 1993). Related to Trench Suction is Slab Roll-Back.
Where does slab suction occur?
Slab suction occurs when a subducting slab drives flow in the lower mantle by exerting additional force down in the direction of the mantle’s convection currents. This flow then exerts shear tractions on the base of nearby plates.
What is the reason why slab pull resist in subducting?
Collisional Resistance
This force directly opposes the slab pull force. It occurs as the heavy basaltic plate is pulled down into the mantle. The collisional force occurs because the mantle, although less dense than the subducting plate, still resists subduction to some extent due to friction.
What do the lithospheric plates move?
Convection currents in the mantle cause the heating of Earth’s plates and therefore, cause them to move. When warm material rises up, the cold material sinks down and this pattern repeats over and over. This causes the plates to rise and move.
What is the effect on a plate when a slab sinks?
As a slab sinks, it pulls on the rest of the plate with a force called slab pull. Scientists are still uncertain about which force has the greatest influence on plate motion. As a slab sinks, it pulls on the rest of the plate with a force(slab pull).
Why is convection current important?
Why is convection important in earth science? Convection currents transfer heat from one place to another by mass motion of a fluid such as water, air or molten rock. The heat transfer function of convection currents drives the earth’s ocean currents, atmospheric weather and geology.
Which plate boundary is destructive?
A destructive plate boundary is sometimes called a convergent or tensional plate margin. This occurs when oceanic and continental plates move together. The oceanic plate is forced under the lighter continental plate. Friction causes melting of the oceanic plate and may trigger earthquakes.
Why does the edge of the plate sink?
The heavier oceanic lithosphere is overridden by the leading edge of the other plate. … This sinking is driven by the temperature difference between the slab and the surrounding asthenosphere, as the colder oceanic lithosphere has, on average, a greater density.
Who proposed the slab pull theory?
In 1975 Forsyth and Uyeda used the inverse theory method to show that, of the many forces likely to be driving plate motion, slab pull was the strongest. Plate motion is partly driven by the weight of cold, dense plates sinking into the mantle at oceanic trenches.
What are the 3 main types of plate boundaries?
- Divergent boundaries — where new crust is generated as the plates pull away from each other.
- Convergent boundaries — where crust is destroyed as one plate dives under another.
- Transform boundaries — where crust is neither produced nor destroyed as the plates slide horizontally past each other.
What is plate boundary?
A plate boundary is a three-dimensional surface or zone across which there is a significant change in the velocity (speed or direction) of motion of one lithospheric plate relative to the adjacent lithospheric plate.
How does convection current and slab pull work together?
As one plate subducts, it sets up convection currents in the upper mantle that ‘exert a net trenchward pull’ ie, acts to suck both the plates together (Wilson, 1993). Associated with the slab suction force is the idea of trench roll-back.
Does the earth crust move?
Earth’s crust, called the lithosphere, consists of 15 to 20 moving tectonic plates. … The heat from radioactive processes within the planet’s interior causes the plates to move, sometimes toward and sometimes away from each other. This movement is called plate motion, or tectonic shift.
Which type of boundary does ridge push occur?
The ridge-push force is created by tectonic plates moving away from a divergent boundary due to their higher elevation than the surrounding ocean floor. These forces are influenced by the high rates of volcanism occurring beneath mid-ocean ridges.
How does gravity affect plate movement?
The main driving force of plate tectonics is gravity. If a plate with oceanic lithosphere meets another plate, the dense oceanic lithosphere dives beneath the other plate and sinks into the mantle: this process is called subduction. … Such convection cells exist inside the Earth’s mantle.