You can use the raw sensors if you wish,but for most cases, youll want to usethe cmdevicemotion class to minimizethis and other forms of noise. Nazca ridge push slab pull b north american ridge push slab pull c indianaustralian ridge push slab pull d eurasian ridge push slab pull 1. This synthesis links many seismic and tectonic processes at subduction zones, including great subduction earthquakes, to the sinking of subducted plate. The importance of slab pull and a global asthenosphere to plate motions. Geoscience videos quiz for rates of plate motion 1. The process is continuous because forces cause opposite sides of the midocean ridge to constantly move apart, making new room for the process to repeat. Plate tectonicswhat are the forces that drive plate tectonics. Plate tectonicswhat are the forces that drive plate. Although it is called ridge push, the term is somewhat misleading. Red areas are the youngest rocks created at midocean ridges. If diving slab pull is the primary driver of plate motion, i dont. Its still in the curriculum though ridge push and slab pull now get a minor mention.
There were slappush earthquakes along mexico and chile. Push technology refers to servers that initiate information updates to clients. Slab pull demo how tectonic plates can pull on each other to speed subduction using paper clips. This force is created as the plate begins to sink into the earths mantle and serves to pull the lower plate further away from the volcanic ridge where it is formed. However, this small contribution causes plates to move too slowly on average unless mantle viscosity is a factor of. Slab pull is a key force acting on plate motion because it has been proven to.
Slab pull demo how tectonic plates can pull on each other to speed subduction using paper clips duration. The sea floor slopes down from the midocean ridge to lower elevations, which are shown in blue. The mantle convection is also involved in slabpull which is caused by the subducting oceanic plate that has been thrusted beneath another plate at a destructive plate margin. Instructor even when the sensors exist,theres a problem with the sensors. These are certainly not a list of all the questions, but it should help guide your studying. Seafloor spreading is the continuous process of forming new igneous rock at midocean ridges by injection of magma that forms new seafloor. Voyage of the indian subcontinent since pangea breakup and. Geologists now believe that the tectonic plates are an active driver of the. This has been the case since the failure of wegeners ideas about polflucht to explain continental drift to the seminal papers by elsasser, solomon and sleep, and forsyth and uyeda on slab pull and ridge push. Ridgepush forces are thought to be second in importance only to the forces of slab pull. The concept of push and pull arent unique to software development the idea originates from logistics and supply chain management. What is the differences between slab pull and ridge push.
This is because it cools as it moves away from the ridge and the boundary between the solid lithosphere and slightly molten asthenosphere becomes deeper the. This is the traditional way to structure a clientserver architecture. Raw sensors do not distinguishbetween earths gravity compared to user accelerations. A push and pull system is differentiated by the schedule of production which, in the context of software, is the schedule of implementation e. Ridge push and slab pull are thought to be the major forces driving the motion of oceanic plates. Oceanic crust is created at a midocean ridge by igneous material being extruded. It shows how the continents moved apart and, in some cases, stitched back together.
Slab pull and the seismotectonics of subducting lithosphere. The process that results when magma rises at a midocean ridge and pushes oceanic plates in two different directions away from the ridge 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. However, ridge push is still considered to be of significance, especially where there is little or no slab pull acting on the plate eg the antarctic plate mentioned above. Ridgepush and slabpull forces are probably the main forces that drive plate motion. Subduction, ridge push, slab pull flashcards quizlet. The energy source for plate tectonics is earths internal heat while the forces moving the plates are the ridge push and slab pull gravity forces. The process that results when magma rises at a midocean ridge and pushes oceanic plates in two different directions away from the ridge slab pull the process that results when a dense oceanic plate sinks beneath a more buoyant plate along a subduction. The feasibility of the slab pull mechanism is also conditioned by the length of the slab. The pacific ocean floor moves much quicker than the atlantic because it has both slabpull and ridge push acting on it, while the atlantic only ha ridge push probably the weaker of the two forces. The heat expelled by the magma expands the lithosphere. Ridge push and slab pull forces are probably the main. This causes it to sink beneath the continental crust in a subduction zone. It was once thought that mantle convection could drive plate motions. Ridgepush is the pushing force exerted by the plates as they move away from the divergent boundary.
The energy source for plate tectonics is earths internal heat while the forces moving the. As the plates pull apart, hot molten material can rise up this newly formed pathway to the surface causing volcanic activity. Ridge push is the lifting and pushing apart of the plates at spreading zones. For the love of physics walter lewin may 16, 2011 duration. In plate tectonics, a divergent boundary is a linear feature that exists between two tectonic plates that are moving away from each other. As a crustal plate moves further from an oceanic ridge, it cools and becomes increasingly dense. Pull technology refers to clients that make requests to servers. Forces that cause what drives plate motion several mechanisms contribute to plate motion that include slab pull, ridge push, and slab suction. Lithospheric plates are part of a planetary scale thermal convection system. Mechanisms of plate motion the university of sydney. 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 midocean ridges as the result of the rigid lithosphere sliding down the hot, raised asthenosphere below midocean ridges. Mantle convection currents, ridge push and slab pull are three of the forces that have been proposed as the main drivers of plate movement based on what drives the plates.
Dynamic earth mantle convection this page from the university of leeds gives an introduction to the drivers of plate tectonics, including links to illustrations depicting ridge push slab pull, ridge bathymetry, mantle tomographic data, plumes, and other topics. The tectonic plates that make up the earths crust are in constant motion. Slab pull is the force exerted by a dense oceanic plate sinking into the mantle at a convergent plate boundary. Seafloor spreading animation earthguide online classroom.
The weight of this sinking, cooling plate causes a major pulling action, which causes the rest of the plate to be pulled downwards as well. Interactions between the forces that drive and resist plate motions cause spatially and temporally localized. Plate motion by alham ahmadzai transform a transform fault or transform boundary, is a type of fault whose relative motion is. As the magma wells up, a number of forces act upon the plate on either side, including gravity, which pulls the new rock down the slope as lava extrudes from the top of the ridge. Slab pull is more important than ridge push 80% vs 20%. The difference between a push and a pull system is how the units of work are assigned to the person who will be carrying out that unit of work. Forces that drive plate motion by alham ahmadzai on prezi. The weight of the plate gradually pulls it deeper into the mantle, and combined with ridgepush it is a major part of the tectonic plate theory. Slab pull is caused by the negative buoyancy of the subducting plate. Animation speculating on the movements of the continents over the.
Ridge push is caused by the potential energy gradient from the high topography of the ridges. 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. This force, which acts to push the plates apart, is nowhere near as strong as the slab pull force, which acts in the subduction zones where plates are destroyed. The ridge pushslab pull model also relies on mantle convection, but in. Driving forces of plate motion department of earth and. Earthquake data and tectonic modeling for subduction zones indicate that the slab pull force is much larger than the ridge push force. The final task involves ipads but you could easily replace with information sheets. Slab pull is considered a boundary force, and from most estimates is responsible for some of the largest forces, or torques in the. Understanding how these forces work provides important insights into how plate boundaries will evolve through time. A lesson to outline the movement of tectonic plates. This lesson covers slab pull, which is one of the forces that affect. Plate motion is partly driven by the weight of cold, dense plates sinking into the mantle at oceanic trenches. Slab pull is that part of the motion of a tectonic plate caused by its subduction.
The history of the development of plate tectonics is centrally tied to the question of what drives plate motions. Ridge push means that the belowcrest magma is light enough and liquid enough to flow to. This force is regarded as a secondary force and is referred to by some as ridge push. Mantle convection currents, ridge push and slab pull are three of the forces that have been proposed as the main drivers of plate movement based on what. These areas can form in the middle of continents or on the ocean floor. According to columbia university, faults where subduction is occurring result in a force known as slab pull. How can slabpull and ridgepush contribute to the movement of a plate at the same time. What is a simple definition of slab pull and ridge push. However, this idea has now changed with the main mechanism determined to be slab pull. Approximately how far would a tectonic plate travel in an average human lifetime.
Mechanisms for plate motion geosciences libretexts. There are a number of competing theories that attempt to explain what drives the movement of tectonic plates. Ridge push or sliding plate force is a proposed mechanism for plate motion in plate tectonics. What is the difference between ridge push and slab pull. This animation illustrates the slabpush and slabpull processes at work at an. Slab pull means the descending plate is dense enough and solid enough to pull the rest of the oceanic plate along, pulling the ridgecrest open to allow magma to the surface.
Use the wall of words, bell ringers, earlier quizzes, types of plate boundaries. This animation of seafloor spreading and plate tectonic evolution of the planet since 200 million years ago is from noaas science on a sphere series. Fast moving plates 5 cmyr, are attached to subducting slabs e. The importance of slab pull and a global asthenosphere to. Slab pull is thought to be a more significant gravitational force acting on plates. There have been two main models of ridge push proposed by geologists. Learn vocabulary, terms, and more with flashcards, games, and other study tools. The difference between push and pull technology comes down to who initiates information updates. Slab pull is caused by the weight of a subducting plate pulling the trailing slab into the subduction zone much like a tablecloth slipping off the table can pull articles off with it. Slab pull, slab trench suction and ridge push forces drive plate motion slab resistance, continental reistance, transform fault resistance and basal drag oppose plate motion when resisting forces become greater than the driving forces, collision between the plates will eventually cease. Because midocean ridges lie at a higher elevation than the rest of the ocean floor, gravity causes the ridge to push on the lithosphere that lies farther from the ridge as molten magma rises at a midocean ridge it heats the rocks around it. In the current understanding of plate motion the movement is driven by the weight of cold, older, dense plate material sinking into the mantle at deep ocean trenches and.
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