The theory of plate tectonics proposes that the earth’s lithosphere is divided into seven major and several minor plates. The movement of the plates results in the building up of stresses within the plates and the continental rocks above, which leads to folding, faulting and volcanic activity. The major plates are surrounded by fold mountains, ridges, trenches and faults.
These plates have been moving very slowly across the globe throughout the history of the earth. Moreover, it may be noted that all the plates without exception, have moved in the geological past, and shall continue to move in the future as well.
Significance of Plate tectonic theory
- For geologists, it is a fundamental principle for study. It is the unifying theory of geology, which further explains large-scale geological phenomena, such as earthquakes, volcanoes, and the existence of ocean basins and continents.
- Plate tectonics theory explains why there are lots of volcanoes in Iceland and Japan, but far fewer in Russia and Africa. This is because Iceland was created by a mid-oceanic ridge. Similarly, Japan is located on a fault line. The constant pressure around the fault line causes many earthquakes and volcanic eruptions.
- For geographers, the theory of Plate tectonics aids in the interpretation of landforms. It ultimately explains why and where deformation of Earth s surface occurs.
- Further, the concept of plate tectonics explains mineralogy. New minerals pour up from the core along with the magmatic ejections. The plate boundaries are the pathways through which rocks from the mantle come out as deposits on lithosphere. These rocks are the source of many minerals. The famous Pacific Ring of fire known for its violent volcanic activity is also a ring of mineral deposits.