From the Los Angeles Times:
“Nearly 1.5 miles beneath Earth’s surface in Canada, scientists have found pockets of water that have been isolated from the outside world for more than 1 billion years.
The ancient water, trapped in thin fissures in granite-like rock, has been bubbling up from a zinc and copper mine for decades in Timmins, Ontario. Only recently have scientists been able to calculate the age of this water and determine that it is the oldest ever discovered — possibly as old as 2.6 billion years, when Earth was less than half its current age. And it may harbor life.”