Rocks are constantly on the move. Eroded by water, sinking into the sea, and ejected by volcanoes, rocks have their very own cycle of existence.
- The rock cycle is the process of rocks weathering away and creating new rocks.
- Over time weathering reduces rock to tiny grains of sand.
- The wind transports the sand, which builds up on seabeds and eventually becomes sedimentary rocks.
- Deep in the Earth, high pressure and temperature melt rocks into magma which is produced during volcanic eruptions.
This ordinary looking rock, found in northern Canada in 2008, is the oldest ever found on Earth.
It contains minerals dating back over 4 billion years.
Most rocks on Earth are a lot younger.
Because Earth's natural processes are constantly breaking down existing rocks...
And creating new ones.
This is ...
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