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Introduction:
The most serious theory of the origin of life on Earth leverages on the existence of minerals from meteorites and the formation of the Earth.
A close link between life and geology:
Life has as origin a series of reactions and transformations of minerals and chemical elements into the oceans. These reactions have modified these components resulting in live products 3800 million years ago.
The earliest forms of life were unicellular structures and microbes: viruses, bacteria and cyanobacteria or blue-green algae.
However the first living beings live in oxygen-free environments: they are in anéorobie. Thus in Australia, we have found old stromatolites from 3,500 million years ago, it is calcareous concretions formed by the activity of cyanobacteria: they are able to release the oxygen in the oceans from solar energy.
But this oxygen does not enrich the aquatic environment or the atmosphere because it is determined by ferrous ions and uranium in solution.
The resulting oxidized iron and uranium were deposited to form the very important deposits of today.
Finally, 2 200 million years ago, a fundamental change took place: the appearance of oxygen in the atmosphere.
Reminder on "Earthcaches": There is no container or logbook on the given coordinates. Just visit the site and answer the questions by e-mail.There is no need to wait for my reply, feel free to log immediately after. If the answers are incorrect, I will let you know. Happy caching!
To validate your visit:
1-. What is the name given to the group of compounds which originated life?
2-. What are the names and locations of the major exploited deposit of oxidized iron and uranium?
3-. What is one of the consequences, at a geological level, of the appearance of oxygen in the atmosphere?
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