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Even for a piece of rock, the Nuvvuagittuq greenstone belt has been around for a long, long time.

In fact, the expanse of bedrock in Canada has been named by scientists as the oldest known place on the Earth's surface.

After seven years of study, tests have shown that the ancient section of the planet's crust is 4.28billion years old, beating the previous oldest known specimen by 250million years.

The Nuvvuagittuq greenstone belt - a swathe of bedrock in Canada - has been identified as the oldest place in the world, dating back some four billion years
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The discovery, on the Eastern shores of the Hudson Bay in northern Quebec, gives scientists an unprecedented insight into how the Earth was formed.

While the age of the Earth itself is estimated at 4.6billion years, most of the original surface has been crushed and recycled through the movement of giant tectonic plates.
Scientists from America and Canada measured tiny variations in the composition of rare elements within the Nuvvuagittuq rocks and determined that the oldest samples were rocks known as 'faux amphibolite', which are thought to be ancient volcanic deposits.

Previously, the oldest known genuine rocks were from a body called the Acasta Gneiss in western Australia, which are 4.03billion years old.

Most of the planet's early surface has been smashed up several times by tectonic activity, making this discovery extremely rare



Jonathan O'Neil, of McGill University in Montreal and Dr Richard Carlson, from the Carnegie Institution for Science in Washington DC, led the study, published yesterday in the journal Science.

Dr Carlson said: 'These are the oldest whole rocks found so far. This gives us an unprecedented glimpse of the processes that formed the early crust.'

He added that the findings suggest continents formed very early in the Earth's history as the Nuvvuagittuq's chemical composition is like that of the volcanic rocks in places where tectonic plates crash together today.

PhD student Mr O'Neil said: 'When I went back this summer and walked there again, knowing they were the oldest rocks in the world, I have to say it was kind of special.'Scientists believe they have identified the oldest place on Earth - a chunk of Canada dating back more than four billion years.

The Nuvvuagittuq greenstone belt is a swathe of bedrock exposed on the eastern shore of Hudson Bay in northern Quebec.

By measuring tiny variations in the composition of rare elements, scientists determined that rock from the site was between 3.8 and 4.28 billion years old.


Source: Daily Mail UK, September 26, 2008