Scientists have identified what could be the oldest rocks on Earth from a rock formation in Canada. The Nuvvuagittuq Greenstone Belt has long been known for its ancient rocks—plains of streaked gray stone on the eastern shore of Hudson Bay in Quebec—but researchers have disagreed on exactly how old they are, per the AP. The new study in Science suggests the rocks have been around about 4.16 billion years, nearly as long as Earth itself, notes Gizmodo.
Work from two decades ago suggested the rocks could be 4.3 billion years old, placing them in the earliest period of Earth's history. But other scientists using a different dating method contested the finding, arguing that long-ago contaminants were skewing the rocks' age and that they were actually slightly younger at 3.8 billion years old. In the new study, researchers sampled a different section of rock from the belt and estimated its age using the previous two dating techniques—measuring how one radioactive element decays into another over time. The different methods "gave exactly the same age," said study author Jonathan O'Neil of the University of Ottawa.
Earth formed about 4.5 billion years ago from a collapsing cloud of dust and gas soon after the solar system came into existence. Primordial rocks often get melted and recycled by the Earth's moving tectonic plates, making them extremely rare on the surface today. Scientists have uncovered 4-billion-year-old rocks from another formation in Canada called the Acasta Gneiss Complex, but the Nuvvuagittuq rocks could be even older. "To have a sample of what was going on on Earth way back then is really valuable," said Mark Reagan with the University of Iowa, who studies volcanic rocks and lava and wasn't involved with the new study.
,
uBlock 
,
and
Ghostery 
)
