Friday, October 3, 2008

Oldest known rock on Earth is discovered

Scientists using geochemical testing say Canadian bedrock more than 4 billion years old4.28 billion years for rock samples taken from the Nuvvuagittuq greenstone belt, making it 250 million years more ancient than any previously discovered rocks.
The Nuvvuagittuq greenstone belt -- an expanse of bedrock exposed on the eastern shore of Hudson Bay in northern Quebec -- was first recognized in 2001 as a potential site of very old rocks. By measuring minute variations in the isotopic composition of the rare earth elements neodymium and samarium in the rocks, the rock samples were found to range from 3.8 billion to 4.28 billion years old. Before this study, the oldest dated rocks were from a body of rock known as the Acasta Gneiss in the Northwest Territories, which are 4.03 billion years old.

Courtesy: United Press International

No comments: