Earth's Oldest Crust Dates to 4.4 Billion Years Ago
Earth's oldest known piece of continental crust dates to the era of the moon's formation.
Australia holds the oldest continental crust on Earth, researchers have confirmed, hills some 4.4 billion years old.
For more than a decade, geoscientists have debated whether the iron-rich Jack Hills of western Australia represent the oldest rocks on Earth. The new findings rely on atom-scale analyses of tiny crystals in rocks that solidified from lava there eons ago. (See also: "Oldest Rocks on Earth Discovered?")
"This confirms our view of how the Earth cooled and became habitable," said study leader John Valley of the University of Wisconsin-Madison, in a statement. "This may also help us understand how other habitable planets would form."
Earth itself is a bit more than 4.5 billion years old, and the researchers hope the new finding
