THE PRECAMBRIAN ERA

The Precambrian sub-divided into:

The Archean Era (about 3960-2500 Mya)

The Proterozoic Era (about 2500-540 Mya)

ACTIVITIES IN THE ARCHEAN ERA

Extensive Orogenesis

The prokaryotes, bacteria and blue-green algae emerged

Formation of Greenstone belts and banded iron ores

Shallow seas appeared.

ACTIVITIES IN THE PROTEROZOIC ERA

Eukaryotic cells and multicellular lives emerged

The Earth experienced warm and moist conditions

The Earth experienced Dry and Cold climate

Soft-bodied marine invertebrates (Earliest known fossils) e.g. Annelids, Sponges, Sea anemones emerged

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THE AGE OF THE EARTH - THE OLDEST MAN ON EARTH IS THE EARTH

THE AGE OF THE EARTH Hey … Just as we celebrate our birthdays to commemorate the day we were born, has it ever occurred to you to ponder on the age of the earth? Don’t you think that there was a day (way back) when the earth was formed? Don’t get it twisted!!! This is no myth. It is a reality. It is REAL!!! The Earth is approximately 4.6 billion years old!!! Sounds absurd??? Well, this figure did not come as a result of fiction or imagination – but by radiometric dating in the early 20 th century. Lead in uranium-rich minerals when dated by early scientists, were able to discover that they were billions of years old. Another pointer to this is that small crystals of Zircon obtained from Jack Hills, Western Australia when dated, was around 4.4 billion years old. One may ask: “How is this possible”? Rocks are aggregate of minerals. Some of these minerals have radioactive elements like Uranium and Thorium. In the process of their decay (radioac...

Lead in Drinking / Groundwater

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GEO SOLUTIONS

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