Not that weâd expect less after the cliffhanger last season. If you havenât yet watched the September 23rd premiere of Chicago Fire, and somehow have managed not to find out who died, donât keep reading. If you have, please join me in my misery.
The Precambrian Super-Eon lasted from the formation of Earth 4,567 million years ago until the start of the Pharerozoic Eon 542 million years ago. It lasted 4.025 billion years. 90% of Earth's history.
Pre-Cambrian (0.6 to 4.6 bya). The PreCambrian represents the first 4 billion years of earth history (approx. 85%). Mostly obscured by a relatively thin veneer of Phanerozoic sedimentary, igneous, and metamorphic rocks.ther portions of PreCambrian terrains include sections of relatively un-metamorphosed volcanics and sediments. These sedimentary sequences reflect the surface conditions at the time of formation and are important to our understanding of PreCambrian terrains and events.