Earth's outer layer may have once a solid shell before it was broken up into huge tectonic plates and trigger extreme events like Earthquake and volcanic eruptions. The new study has published from University of Maryland, Curtain University and the Geological Survey of Western Australia.

According to LIVE SCIENCE, the Earth was not always a dynamic planet. The planet's first outer layer was a single, solid but deformable shell. The new study finds support for the idea that the Earth's crust as "a stagnant lid" that is formed the planet's outer shell early in Earth's history. The study co-author Michael Brown from the University of Maryland has reported the news.

Indian Express has reported, to investigate the history of Earth's outer shell. Brown and his colleagues have studied the planet's ancient rocks, specifically from a large area of Ancient crust in Western Australia. The researchers also studied the ancient rocks that are related to the volcanic activity which occurs the borders of tectonic plates.

The researchers have stated that the ancient crust's Pilbara granite rocks have a chemical composition that is similar to coucal basalt rocks in the region. The scientists looked into whether the ancient basalt could have created the granite without a volcanic source, therefore forming the crust without plate tectonic activity.

The scientists have created experimental models, which they used to replicate how the Earth's outer layer could have formed without planet tectonics. The scientists formed the models by using the Coucal basalts and Pilbara granites from the ancient crust.

The basalts could have formed the Pilbara granites in a so-called stagnant lid in the scenario. The study found that the pressure and temperature of a single shell covering the planet would have stimulated the melting of basalts to form granites.

However, scientists believe that a multi-stage process produced Earth's first continents in a 'stagnant lid'. The details research is published online in the Journal Nature.