The Greenstone Belts occur as belts of deformed volcanic and sedimentary strata and get their name from the presence of
green minerals (Actinolite,amphiboles,Chromium muscovite “fuchsite”, epidote, green chlorite and serpentine).
These ancient rocks are among the oldest in the World.
The Barberton Greenstone belt is one of the oldest and best exposed Archaean greenstone belts on Earth and is almost 3.5 billion years old.
The small and beautiful "Makhonjwa Mountain Range"close to Barberton, where gold and asbestos deposits occur, stretches from Jeppe’s Reef to Oshoek and from
Shiyalongubo Dam to Queen’s river. It is known world wide in geological circles as a treasure house of other significant geological phenomenae.
This range is also referred to as the ‘Genesis of Life’,because it's geology includes the best preserved ancient Achaean rocks on earth.
These ancient rocks are 3.5 billion years old and they are so well preserved that their fossils accurately record the earliest life forms on the planet, as well as evidence of the first massive meteorite impact on record, possibly related to the formation of our moon.
If you were able to travel back in time to visit Earth during the Archaean period you would not recognize it as the same planet we inhabit today. FOR MORE CLICK HERE http://www.windows.ucar.edu/tour/link=/earth/past/Archean.html
The atmosphere was very different from today it most probably consisted of methane, ammonia, and other gases which would be toxic to most life on earth today.
It was during this time, that the Earth's crust cooled enough in order for rocks and continental plates to begin forming.
The first forms of life appeared on Earth during the early Archaean period.
The periods can roughly be divided as follows:-
Early Archaean 3.9 - 3.3. billion years ago; Mid Archaean 3.3 - 2.9 billion years ago; Late Archaean 2.9 - 2.5 billion years ago.
The oldest known fossils date back to about 3.5 billion years ago, and consist of bacteria microfossils. All life during the Archaean period was bacterial.
Stromatolites, were colonies of photosynthetic bacteria which today have been found as fossils in the early Archaean rocks of Barberton.
Stromatolites were common during the late Archaean age.