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Stromatolite fossil dating

Some minerals have magnetic properties and are directed towards the north magnetic pole when in aqueous suspension, for example clays.

But when laid on the ground, they are fixed to the position that the north magnetic pole was at the time.

Most living things could not have survived breathing the air of that time.

So, there are different types of fossils: Obviously fossils became more common after the appearance of hard parts (shells, teeth, bones …), 543 million years ago (Cambrian Explosion).Billions of cyanobacteria producing oxygen, constantly, over many millions of years made an atmosphere that could support life as we know it.The beginning of the Cambrian Period Marked a time of decrease for the stromatolites but oxygen breathing life forms exploded in the oceans of that period.This unique fossil is also very ancient, dating back to the boundary of the Archean and the Proterozoic in Precambrian time.This was a time on Earth when the environment was still hostile to life as we know it today.If we look at what coordinates are oriented such minerals at the site, we can associate it with a particular time.This dating is used on clay remains and as the magnetic north pole has been several times in the same geographical coordinates, you get more than one date.Description: Precambrian stromatolite is the oldest of all fossils, and with much labor (cutting and polishing), it is most beautiful.The banding that commonly appears in stromatolite is a record of the growth patterns of colonies of microorganisms, principally photosynthetic cyanobacteria.It is the process of photosynthesis combined with the growth of the cyanobacteria that creates the distinctive dome-shaped, finely layered rocks we call stromatolites.As the cyanobacteria grows it uses up the carbon dioxide in the surrounding water.

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