How can you say the earth is still very active?

Question

Read the paragraph under the heading of “Internal structure of the earth” and answer the question.

Internal Structure of the Earth : 

Let us look at the internal structure of the Earth we live on. We can see the continuity from the early days of the formation of the earth as we try to look deep inside the Earth! It took us years of scientific investigation and analysis of data to form an understanding of the interior of the Earth. The main reason for this is that even the deepest mines we have dug do not go beyond a few kilometres under the surface while the radius or the distance to the centre of the earth is over 6000 kilometres.

How can you say the earth is still very active?

Answer 1

• The matter deep inside the mantle shoots up through volcanoes and fissures on ocean floors. 
• In many regions on the earth part of the earth’s crust enters into the mantle and once again becomes molten. 
• The crust is still being changed by earthquakes, volcanoes, subduction of land and rise of mountains due to the processes happening deep down the earth. 
• This constant process of formation and destruction of the earth’s crust explains the fact that the earth is still very active.