Dating back to the precambrian era executive dating agencies brisbane
Resources and references * Dates from the International Commission on Stratigraphy's International Stratigraphic Chart, 2009. Speer created the original Archean page, 3/9/1997; Ben M.
Waggoner created the original Hadean page, 2/20/1996; Dave Smith combined the content into a single page, adapted it to the new site format, and made some content changes, 7/7/2011; Shark Bay photo courtesy of Allen Collins (?
That is why the traditional boundary between the distant geological past and the period of life on Earth, is defined at the start of Cambrian.
Cambrian is the first part of Phanerozoic, which traditionally denotes the era, where life has existed on Earth.
The Archean eon, which preceded the Proterozoic eon, spanned about 1.5 billion years and is subdivided into four eras: the Neoarchean (2.8 to 2.5 billion years ago), Mesoarchean (3.2 to 2.8 billion years ago), Paleoarchean (3.6 to 3.2 billion years ago), and Eoarchean (4 to 3.6 billion years ago).* If you were able to travel back to visit the Earth during the Archean, you would likely not recognize it as the same planet we inhabit today.
The atmosphere was very different from what we breathe today; at that time, it was likely a reducing atmosphere of methane, ammonia, and other gases which would be toxic to most life on our planet today.
Left: A Hubble Space Telescope image of a star-forming region of Nebula M16 (Eagle Nebula).
Sometime during the first 800 million or so years of its history, the surface of the Earth changed from liquid to solid.
The spacecraft was about 10,500 kilometers (6,500 miles) from the asteroid.
The sun formed within such a cloud of gas and dust, shrinking in on itself by gravitational compaction until it began to undergo nuclear fusion and give off light and heat.
Also during this time, the Earth's crust cooled enough that rocks and continental plates began to form.
It was early in the Archean that life first appeared on Earth.