The earth formed about 4.5 billion years ago.
Here is a short but good outline of earth changes from its formation to its differentiation into layers (core, mantle), the development of an atmosphere and oceans, and the beginning of continent-development.: http://www.globalchange.umich.edu/globalchange1/current/lectures/first_billion_years/first_billion_years.html
And here's a more technical outline with nice illustrations: http://astrobiology.ucla.edu/pages/res3a.html
Two slightly different scenarios for very early surface environment: There is one prevailing view that the surface was a hot, volcanic environment until about 3.8 billion years ago. A more recent interpretation of data is that " Earth began a pattern of crust formation, erosion, and sediment recycling as early in its evolution as 4.35 billion years ago," according to Bruce Watson of Rensselaer Polytechnic Institute. The planet would still have been quite hot, and the atmosphere would have consisted only of carbon dioxide, water, and volcanic gases.--idea and supporting data presented in the well-respected journal Science in 2005.
More at :
http://www.livescience.com/forcesofnature/050505_early_earth.html
2007-03-09 04:12:08
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answer #1
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answered by luka d 5
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Yes. But no.
I think you are referring to the continents eons ago - Pangia and Gundawanaland. However, life was in existence at some level even then.
When first formed, the Earth was a molten ball of ash and methane on a volcanic landscape.
2007-03-07 09:03:26
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answer #2
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answered by Anonymous
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