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  • Archean - Wikipedia
    The Archean represents the time period from 4,031 to 2,500 Ma (million years ago) The Late Heavy Bombardment is hypothesized to overlap with the beginning of the Archean The oldest known glaciation occurred in the middle of the eon
  • Archean Eon | Atmosphere, Timeline, and Facts | Britannica
    Archean Eon, the earlier of the two formal divisions of Precambrian time (about 4 6 billion to 541 million years ago) and the period when life first formed on Earth
  • 8. 4: Archean Eon - Geosciences LibreTexts
    The Archean Eon, which lasted from 4 0–2 5 billion years ago, is named after the Greek word for beginning This eon represents the beginning of the rock record
  • The Archean Eon - Smithsonian Institution
    The Archean Eon (4 to 2 5 billion years ago) During the Archean Eon, methane droplets in the air shrouded the young Earth in a global haze There was no oxygen gas on Earth Oxygen was only in compounds such as water
  • Archean - New World Encyclopedia
    The Archean (or Archaean) eon is an interval of geologic time of about 1 4 billion years, beginning with the formation of Earth's crust and the oldest Earth rocks 3,960-3,800 million years ago (mya) and continuing until its boundary at 2,500 mya, with the Proterozoic eon
  • What is Archean? - Earth. com
    Although only a few mineral grains are known from the Hadean era, all rock formations exposed on the surface are from the Archean period Geologists have found Archean rocks throughout the world, in Greenland, Scotland, Brazil, India, Australia, and other regions
  • Introduction to the Archean Eon: Earth’s formative years
    Discover the fascinating history of Earth’s formative years in this comprehensive guide to the Archean Eon Explore the geology, life, and mysteries of this ancient era
  • The Archean Eon and the Hadean - University of California Museum of . . .
    Our oldest fossils date to roughly 3 5 billion years ago, and consist of bacteria microfossils In fact, all life during the more than one billion years of the Archean was bacterial The Archean coast was home to mounded colonies of photosynthetic bacteria called stromatolites
  • What Happened in the Archean Eon? [4. 0 to 2. 5 billion years ago]
    In the Archean Eon, oxygen filled the atmosphere, and most of the world’s iron ore was deposited Because the Earth’s conditions stabilized, eukaryotic and multicellular life could finally emerge in the Proterozoic Eon
  • The Archean Eon (4000-2500 Ma) - Maricopa Open Digital Press
    The Archean Eon lasted from 4 0 to 2 5 billion years ago and is named after the Greek word for beginning This eon represents the beginning of the rock record Although there is current evidence that rocks and minerals existed during the Hadean Eon, the Archean has a much more robust rock and fossil record Late Heavy Bombardment





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