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Outer shell of Earth penetrated tectonic plates: scientists observe such phenomenon for the first time

Outer shell of Earth penetrated tectonic plates

The Scientists suggest that significant changes are taking place on our planet. They developed a theory confirming that the Earth's outer shell penetrated the tectonic plates. According to that theory, the entire outer shell of the planet is divided into plates that are constantly moving. Moreover, the greatest activity is observed at the boundaries between these plates. Until now, science has no exact knowledge of how plate tectonics formed and when exactly this process started.

Alexander Webb, who is a leading scientist in the Division of Earth and Planetary Sciences and the Space Research Laboratory at the University of Hong Kong, believes that the reason is in the heating of the outer shell. In the early stages of the planet's formation, it heated up to a process of expansion and formation of cracks.

All of them eventually united into a global network, dividing the early shell of the Earth into plates. The model created by the scientists demonstrated that process by tracking the stress and strain that the shell experiences. On average, it can withstand about 1 km of thermal expansion. But with additional expansion, rapid cracking occurs.

The model is very simple and contrasts with the basic physical principles of the Earth science. Until the 1960s, the soil processes and the distribution of oceans and continents were explained by various hypotheses, including the expansion hypothesis. The scientists argued that strong earthquakes, mountain building and land mass distribution could be a consequence of the expansion of the Earth.

But since the main internal source of Earth's heat is radioactivity, and the constant decay of radioactive elements means that less heat becomes available over time, the new hypothesis rules out thermal expansion and assumes the opposite process - thermal contraction. Alexander Webb and his colleagues believe that the early lithosphere of the Earth underwent thermal expansion when considering the main mechanisms of heat loss that may occurred in the early periods of the Earth.

A volcanic activity could become dominant. It has had an irreversible effect on the outer shell of our planet, forming cold soil materials that rise to the surface. But the Earth gradually cooled down and the production of internal heat and volcanic activity slowed down. New modeling suggests that if the Earth's solid lithosphere is thermally expanded enough, it will collapse, and the rapid growth of the fracture network will divide the Earth's lithosphere into plates.