What Was Happening on Earth at This Time The Precambrian is the earliest of the geologic ages, which are marked by different layers of sedimentary rock. Laid down over millions of years ...

The Precambrian eon is vast ... producing enough energy and heat to vaporize any water or melt any rock that may be present. Gravity also helps separate heavy elements from lighter ones.

In the desert areas of Namibia, Oman, and Saudi Arabia, research work has revealed unusual structures that are probably due ...

Paleontologists now know that the Precambrian actually did swarm with ... This makes it possible to tell if the carbon in a rock had ever been inside a living thing. Consider, for instance ...

Dolomite: Sedimentary rock composed of calcium magnesium carbonate ... dioxide into organic compounds using energy from sunlight. Precambrian: Geologic period extending from ~4.6–0.5 bya ...