Slab pull is that part of the motion of a tectonic plate caused by its subduction. 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. This force and slab suction account for almost all of the force driving plate tectonics. The ridge push at rifts contributes only 5 to 10%.Carlson et al. (1983) in Lallemandet al. (2005) defined the slab pull force as:
K is 4.2g (gravitational acceleration = 9.81 m/s2) according to McNutt (1984);
Δρ = 80 kg/m3 is the mean density difference between the slab and the surrounding asthenosphere;
L is the slab length calculated only for the part above 670 km (the upper/lower mantle boundary);
A is the slab age in Ma at the trench.The slab pull force manifests itself between two extreme forms:
The aseismic back-arc extension as in the Izu–Bonin–Mariana Arc.
And as the Aleutian and Chile tectonics with strong earthquakes and back-arc thrusting.Between these two examples there is the evolution of the Farallon Plate: from the huge slab width with the Nevada, the Sevier and Laramide orogenies; the Mid-Tertiary ignimbrite flare-up and later left as Juan de Fuca and Cocos plates, the Basin and Range Province under extension, with slab break off, smaller slab width, more edges and mantle return flow.
Some early models of plate tectonics envisioned the plates riding on top of convection cells like conveyor belts. However, most scientists working today believe that the asthenosphere does not directly cause motion by the friction of such basal forces. The North American Plate is nowhere being subducted, yet it is in motion. Likewise the African, Eurasian and Antarctic Plates. Ridge push is thought responsible for the motion of these plates.
The subducting slabs around the Pacific Ring of Fire cool down the Earth and its core-mantle boundary. Around the African Plate upwelling mantle plumes from the core-mantle boundary produce rifting including the African and Ethiopian rift valleys.
i have a neobydium magnet of grade n40 , the diameter of magnet is 15mm and thickness is 10 mm ,
now i want to calculate the pull force between this magnet and a steel plate when there is no gap between them ;
& in second case i want to calculate the pull force when i put a 0.15mm copper plate...
Hi guys,
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I've bought a spring scale that measures max 50 gram, so very accurate.
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For an undergraduate project, I need a magnet with a magnetic dipole strength of 0.3 A*m^2. However, all distributors I can find only list their magnets in terms of "pull force" which appears to be defined as the force between a magnet and a steel plate. How do I find a magnet with the dipole I...
Hello! I'm posting this because I cannot find this type of question and analysis anywhere!
What are the force and torque equations describing the following?
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2. The cylindrical tube is...
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I am proposing using...
Hi Guys,
I am going to restart the discussion in the following thread
https://www.physicsforums.com/threads/calculate-pull-force-of-magnet.162157/
I working on similar system where i am interesting to calculate the pull force of permanent magnet on nanoparticles in water suspension. I am not...
Hi,
Can somebody give me the formula for pull force of ring magnet(permanent. not solenoid or electric) on a metal rod.
Also is the formula for pull force by a solenoid given below correct. If not let me know the correct one for the below.
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N =...
Homework Statement
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I am suppose to provide an equation to calculate the force that a disk magnet pulls a steel ball with respect to the distance between those two objects.
My idea is to calculate the difference between the energy density with and without the ball and then calculate...
I'm trying to predict the possible pull force of some electromagnets from the following equation:
FPull= ( n x I ) 2 μ0\frac{A}{(2 g ) ^ 2}
F : Force.
n : Number of turns.
I : Current.
μ0 : permeability of air.
A: Area in m2
g : the gap that is separating the electromagnet and the object...
Coverting Amp to pull force??
I am trying to figure out a way to covert amps to pull force(lbs). I have a known amp that I would like to find out the pull force in lbs.
I have 2.8 amp @ 120v and would like to know the pull force that is needed to turn this type of amperage.
Hallo all,
I've been looking around to find the best way to calculate the magnetic field generated by current flowing through copper wire... There were many sites I've found but its kinda confusing
One of the laws:
I thought it was simple to determine the magnetic field... Is there...
Hello. I'm a cabinetmaker and my college physics courses are 25 years behind me now. I'd consider it a kindness if someone would answer a question for me regarding magnetism.
I have a magnetic strip that is described as having 6.2 lb. of magnetic pull force per lineal foot, 1" wide and 0.020"...
Hi PF,
A disclaimer, I am no good at Physics or math.
My question:
When calculating the pull force between two magnets it seems to always be calculated at an angle perpendicular to the surface of the magnet.
I was wondering what effect on the force required to "pull" one magnet away...
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Homework Statement
What would be the necessary magnetic field strength needed to pick up a 0.1543 lb. magnetic object 0.238 meters away? (I am trying to find a permanent magnet, not an electromagnet to accomplish this)
(the pull force of the permanent magnet I am using is 4.7 lb)Homework...
Okay i am new to this site so i figured this would be the best place to post this. I need an equation for my project i am working on.
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