The oldest known rock on Earth is found along the northeast coast of Hudson Bay, Canada.
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Courtesy of Jonathan O'Neil

Scientists Discover the Oldest Known Rock on Earth
News story originally written on September 26, 2008

Earth is more than four and a half billion years old. But there are very few things around from the Earth’s early days. That’s because our planet is a great recycler. Most of the rocks that were formed when Earth was young have been mashed, melted, or eroded into sand as plate tectonic forces move them around. So pieces of rock from the Earth’s early crust are not easy to find.

But recently, scientists found rocks from Canada that are 250 million years older than any other known rocks. The scientists studied the chemistry of the rocks to find out how old they are. Some of the rock samples were as young as 3.8 billion years old. Others were as much as 4.28 billion years old. These oldest rocks may have formed from ancient volcanoes.

These rocks come from an area on the eastern shore of Hudson Bay in northern Quebec called the Nuvvuagittuq greenstone belt. Scientists have known for several years that the rocks in this area were very old. Now we know how old!

Last modified September 26, 2008 by Lisa Gardiner.

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