Oldest Known Rock on Earth Discovered

Researchers find oldest rocks on Earth

Canadian bedrock more than four billion years old may be the oldest known section of the Earth's early crust. Scientists at the Carnegie Institution used geochemical methods to obtain an age of 4.28 billion years for samples of the rock, making it 250 million years more ancient than any previously discovered rocks. The findings, which offer scientists clues to the earliest stages of our planet's evolution, are published in the September 26 issue of Science.