Ancient Earth

The rocks that first formed the Earth’s surface have been destroyed by erosion and plate tectonics. The oldest known crystals are tiny zircons (zirconium silicate) that formed about 4.3 billion years ago in the very early crust of the Earth. They were later eroded and then reformed into sandstones about 3 billion years ago. Today these sandstones are found in Western Australia.


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How the Moon formedEarth's StructureTectonic Plates