White Lion
Oil Painting
One day of Assistant
My low back pain was almost healed.
Today I went swimming with Motohiro today .
Fortunately the day we plan to go to the zoo will be fine by the forecast.
The Earth
Our Earth was born 4.6 billion years ago.
The most continent has been formed up from 4.4 billion years ago to 3.0 billion years ago.
But the rocks of the seabed is formed 0.2 billion years ago.
The thickness of the continental crust is 20- 70 km average density 2.8 g / cubic cm
The average thickness of the oceanic crust is about 6 km average density 3.0 g / cubic cm
So we can imagine that continental plates are afloat on the mantle.
The other place of the earth is occupied by the oceanic plate of heavy specific gravity .
Moreover, the movement of the sea floor plate is so much earlier than the continental plate.
It is that the interior of the Earth are constantly moving.
This is what we must not forget.

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