Plate tectonics is primarily caused by Earth's cooling mechanism, which generates convection currents in the planet's mantle that trigger slow but constant tectonic plate movement. This phenomena occurs on the boundaries of adjacent plates, which are classified as divergent, convergent and transform boundaries.Know More
The Earth's outermost mechanical layer is referred to as the lithosphere. This rigid stratum comprises the planet's crust and topmost portion of the mantle. The lithosphere is broken into massive, constantly shifting blocks called plates. The two types of plates are called continental plates and oceanic plates.
Two of the sources of Earth's internal heat are the primordial thermal energy it retained during the planet's initial formation and the decay of radioisotopes. Extreme temperatures within Earth's core generate convection cells that cause the mantle to move. A convection current is produced when warm material moves up, cools and then moves down. As it sinks, the material is re-heated and it moves up again, causing the entire process to repeat. The constant movement of the mantle triggers the plates that are located on top of it to constantly move as well.
Two forces that are influenced by and also initiate mantle convection are known as "ridge push" and "slab pull," or "subduction pull." New crustal plates are formed due to a ridge push, while old plates sink down due to a slab pull. A combination of a ridge push and a slab pull causes oceanic plates to move.Learn more about Plate Tectonics
Without plate tectonics, there would be no mountains, earthquakes, volcanoes, tsunamis or continental drift. If the Earth did not move, there may not be any continents at all.Full Answer >
According to the Physics Department of the University of Tennessee Knoxville, evidence for plate tectonics has been found by studying continental shapes and comparing fossils. It notes that modern evidence for plate tectonics is much stronger than when it was first offered as a theory.Full Answer >
Very slow currents in the relatively plastic lower mantle, or aesthenosphere, are thought to push the crustal plates along and drive the process of plate tectonics. These currents are caused by convection, with the mantle rock being heated from below via radioactive decay and thus becoming less dense than the rock above. These hotter rocks move slowly upward, displacing the rock above and forcing it down in an elliptical motion.Full Answer >
Plate tectonics theory, formerly known as the theory of continental drift, is well supported in geology, geography and biology. It has the power to explain many phenomena, such as volcanoes and earthquakes. The theory provides a working model for analyses of phenomena that scientists observe. This explanatory power is, itself, strong evidence that the theory is correct.Full Answer >