Plate Tectonics

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The Plate which is known as the tectonics is from Late Latin word: that is the tectonicus from Ancient Greek.  It is said that tectonics pertaining to building is a scientific theory which is said to be describing the large-scale that is the motion of seven large plates. And the movements that are from the plates of a larger number which is also said to be of smaller plates of planet earth's lithosphere. The tectonic processes are said to begin on Earth which is between 3.3 and 3.5 billion years ago. The model that generally is said to be built on the concept of continental drift is the idea which was developed during the first decades of the 20th century. The geoscientific which we are aware of community accepted theory of the plate-tectonic after seafloor that is said to be spreading was validated in the late 1950s and early 1960s.

What are Tectonic Plates

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The lithosphere which is said to be one of the layers of the atmosphere is a rigid outermost shell of a planet that is the crust and upper mantle which is said to be broken into tectonic plates.

Tectonic plates are said to be able to move because the Earth's lithosphere has greater mechanical strength than the underlying asthenosphere. 

Plate Tectonic Theory

The outer layers of the Earth are said to be divided into the lithosphere and asthenosphere. The division of both the layers which is said to be based on differences in mechanical properties and in the method that is for the transfer of heat. The layer that is of the lithosphere is cooler and more rigid so we can say that  while the asthenosphere is hotter and flows more easily as compared to lithosphere. In terms of transfer of the heat the lithosphere loses heat by conduction method whereas on the other hand the asthenosphere also transfers heat by method of convection and has a nearly adiabatic temperature gradient as well.  We can say that this division conclude that it should not be confused with the chemical subdivision of these same layers into the mantle that is the comprising of both the asthenosphere and the mantle portion of the lithosphere and the crust which is said to be given piece of mantle may be part of the lithosphere.

The key principle of the plate which are the tectonics plates is that the lithosphere that generally exists as separate and distinct tectonic plates ride on the fluid-like visco-elastic solid asthenosphere. The motion of the Plate generally ranges up to a typical 10–40 mm/year that is the mid-Atlantic Ridge which is about as fast as fingernails grow to about 160 mm/year so we can say that the Nazca Plate is about as fast as hair grows. 

What is the Theory of Plate Tectonics

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It has generally been accepted that the plates which are known as the tectonic plates are able to move because of the relative density that is of oceanic lithosphere and the relative weakness of the asthenosphere. When there is a new crust in it then that generally forms at mid-ocean ridges  which forms the oceanic lithosphere. And it is initially less dense than the underlying asthenosphere and it becomes denser with age as it conductively cools and thickens. We can conclude that the greater density of the old lithosphere relative to the underlying asthenosphere that generally allows it to sink into the deep mantle at subduction zones that is providing most of the driving force for plate movement. The weakness which is of the asthenosphere generally allows the tectonic plates to move easily towards a subduction zone.

FAQ (Frequently Asked Questions)

Q1. Explain Where are the Tectonic Plates?

Ans: The outermost part of the planet that is Earth's structure is known as the lithosphere. The lithosphere generally consists of the crust and small portion of the upper mantle. The lithosphere is a layer which is said to be divided into a number of tectonic plates. These plates generally move and interact with one another and is  said to be driven by conventional forces within the Earth.

Q2. Explain What are the 7 Tectonic Plates?

Ans: There are some of the major as well as the minor and micro tectonic plates. There are seven major plates: that are as follows: African, Antarctic, Eurasian, Indo-Australian, North American, Pacific and South American.

Q3. Explain How Tectonic Plates are Formed?

Ans: The plates which we are talking about are the interlocking slabs of crust that float on Earth's viscous upper mantle and this is how they are formed. Now we see that the report says  that other researchers have estimated that a global tectonic plate system emerged around 3 billion years ago.

Q4. Explain Which is the Best Definition of a Tectonic Plate?

Ans: A tectonic plate which is also known as the  lithospheric plate is said to be massive which we can say that it is an irregularly shaped slab of solid rock that is generally composed of both continental and oceanic lithosphere.  By contrast we can say that  the crust which is the oceanic crust is composed of basaltic rocks which are much denser and heavier.