3-5 billion years of Earth

3-5 billion years of Earth - Earths history is divided into...

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Earth’s history is divided into two main parts, the Precambrian and the Paleozoic. The Precambrian lasted from roughly 5 billion to 540 million years ago. And the Phanerozoic began at 540 million years ago and continues to today. The main distinction between the two is that, the Phanerozoic begins the evolution of abundant, multi-celled organisms with complex life histories. Organism in the Precambrian were sparse and relatively simple. A lot of what is known of Earth’s Hadean derives from study of lunar rocks & impact features… The Earth was very dynamic and hot, but with internal differentiation… The Hadean is often metaphorically described as “Hell on Earth” and interpreted as a period of heavy bombardment from meteors Geologic age of zircons from Australia indicate the existence of continental land masses at about 4.4 billion years ago. Continental rock consists of what is called granite. Granites have a distinctive composition of the minerals quartz, feldspar, mica and
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3-5 billion years of Earth - Earths history is divided into...

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