50 years ago, scientists thought they had found Earth’s oldest rocks
Excerpt from the July 21, 1973 issue of Science News
![photo of bedrock in Canada](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2023/07/070723_lsh_oldest-rock_feat.jpg?fit=1030%2C580&ssl=1)
The oldest known rock on Earth, dating to about 200 million years after the planet formed, lies within bedrock in northeastern Canada (shown).
Jonathan O'Neil/NSF