Define mantle plume and explain its role in plate tectonics. (150 words)
A mantle plume is an upwelling of abnormally hot rock within the Earth’s mantle. The heat from this extra hot magma causes melting and thinning of the rocky crust, which leads to widespread volcanic activity on Earth’s surface above the plume. The following are the roles of mantle plumes in plate tectonics:
- Mantle plumes transport primordial mantle material from below the zone of active convection that produces time-progressive volcanic chains.
- Mantle plumes act as a driving force for plate tectonics and play a crucial role in the Earth’s heat budget.
- Mantle plumes can break up continents and cause the formation of rift valleys and basins, which eventually lead to the formation of new oceans.
It is important to note that mantle plumes are different from plate tectonics, which describes the movement of the Earth’s lithospheric plates. However, mantle plumes and plate tectonics can interact, and mantle plumes can influence the movement of lithospheric plates. The Hawaiian Islands, for example, are believed to have formed from a mantle plume that caused a plate to move over it, resulting in a chain of volcanic islands.