Cool Earth - 4.4 Billion Year Old Australian Zircon Reveals The Early Genesis Of The Planet
Sunday, February 23, 2014 - 23:20
in Earth & Climate
Zircon crystals from Western Australia's Jack Hills region crystallized 4.4 billion years ago, building on earlier studies that used lead isotopes to date Australian zircons and identify them as the oldest bits of the Earth's crust. The microscopic zircon crystal is now confirmed to be the oldest known material of any kind formed on Earth. A new study strengthens the theory of a "cool early Earth," where temperatures were low enough for liquid water, oceans and a hydrosphere not long after the planet's crust congealed from a sea of molten rock. The study reinforces the belief that Earth had a hydrosphere before 4.3 billion years ago and possibly life not long afte. read more