3 point of importance of crust
******importance not definition******
Answers
Answer: After the formation of the Earth 4.5 billion years ago, the heavier objects like iron moved to the core and the lighter elements like water settled at the crust. The rocks get redistributed inside the crust during natural process of eruption of lava, consolidation of rock particles, erosion, solidification and re‐crystallization of porous rock. This layer of Earth is very thin when compared to other layers of the Earth.
In general, the Earth's crust is made of metals and minerals like iron (32%), oxygen (30%), silicon (15%), magnesium (14%), sulfur (3%), nickel (2%) and some traces of aluminum, calcium. The temperature of the Crust is around 870°C where the rocks start to melt.
The crust of the Earth is broken in to many pieces called plates. These plates float on the mantle (next layer) smoothly, but sometimes they stick together to build up pressure and the rocks bend ultimately leading to an Earth quake. Tectonics is the theory that deals with the movement of these plates.
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