• 1 Meaning & Historical aspects
• 2 Key principles
• 3. Modern plate tectonic theory
• 4 Types of plate boundaries
o 4.1 Transform (conservative) boundaries
o 4.2 Divergent (constructive) boundaries
o 4.3 Convergent (destructive) boundaries
• 5 Driving forces of plate motion
o 5.1 Friction
o 5.2 Gravitation
o 5.3 External forces
o 5.4 Relative significance of each mechanism
• 6 Current plates
o 6.1 Major plates
o 6.2 Minor plates
• 7 Plate Movement
• 8 Explanation of magnetic striping
• 9 Plate tectonics on other planets
o 9.1 Venus
o 9.2 Mars
o 9.3 Galilean satellites
o 9.4 Titan
• 10. Bibliography
1. Meaning & Historical aspects:-
□ Tectonics term is taken from the Late Latin tectonicus, from the Greek: τεκτονικός "pertaining to building".
□ This theory describes the large scale motions of Earth's lithosphere.
□ A similar process likely takes place on other celestial objects when they are sufficiently similar to Earth.
□ The theory builds on the bases of the older concepts of continental drift, developed during the first decades of the 20th century by Alfred Wegener, and seafloor spreading theory, by Hess and Deitz in the 1960s.
2. Key principles:-
□ The key principle of plate tectonics is that the lithosphere exists as separate and distinct tectonic plates, which ride on the fluid-like (visco-elastic solid) asthenosphere.
□ Tectonic plates consist of lithospheric mantle overlain by either of two types of crustal material: oceanic crust (in older texts called sima from silicon and magnesium) and continental crust (sial from silicon and aluminium).
□ Average oceanic lithosphere is typically 100 km thick, its thickness is a function of its age: as time passes, it conductively cools and becomes thicker. Because it...
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