0Introduction:
The movement of the earth's plate relative to each other due to the adiabatic force generated by the thermal energy from the earth's interior is called plate tectonics. The earth's plate can generally be of 2 types - Continental plate (which is wholly located in the continental part, e.g. Eurasian plate) and Oceanic plate (which is entirely located in the ocean plate, e.g. Pacific plate). Due to plate tectonics, many geophysical phenomena occur resulting formation of many geomorphic landforms.
Plate tectonics can broadly be classified into three major types as under-
1) Convergent Plate Tectonics:
When two plates move towards each other, i.e. converge, they collide with a release of a strong wave of energy in the form of an earthquake. Due to this collision, one plate moves over another and more substantial plate subducts into the other plate, thereby, undergoing a process called folding of plates resulting in the formation of Fold Mountains. When this type of tectonics occurs in the middle of the ocean, the resultant earthquake is coupled with the creation of a gigantic wave of water called Tsunami.
Example: Formation of the Himalayas due to the convergent plate tectonics of Indian Plate and the Eurasian plate which causes folding of the plates resulting in the distinct formation of 3 folds as the three essential ranges of the Himalayas as the Himadri, the Himachal and the Siwalik.
2) Divergent Plate Tectonics:
When one plate moves away relative to another adjacent plate creating a vent or gap between them, it is called Divergent Plate Tectonics. It occurs both in the continental surface as well as the oceanic surface. Due to this tectonics, a gap is generated between the plates from which magma from the asthenosphere comes out in the form of volcanos and results in the formation of volcanic mountains. If this happens in the middle of the ocean, it results in the creation of mid-oceanic ridges.
Example: Ring of Fire in the Pacific Ocean is the adjoining regions of many plates such as Indian Plate, Pacific Plate, Sunda Plate, Philippines Plate, etc. which is prone to volcanic activities, earthquake and tsunamis.
3) Transform Plate Tectonics:
When one plate slides over another plate perpendicularly, it is called Transform Plate Tectonics. Due to this tectonics, faulting occurs, which is a process by which a portion of land gets displaces from its earlier position.
Example: Formation of San Andreas Fault in California due to the transform plate tectonics of the Pacific Plate and the North American Plate.
Thus, plate tectonics is a natural phenomenon which results in the Continental drift (proposed by Alfred Wegener) and Sea Floor spreading (offered by Henry Hess) and island forming in nature.
