The Bakken Shale Formation—a 200,000-square-mile shale deposit below parts of Canada and North Dakota—has supplied billions of barrels of oil and natural gas to North America for 70 years. A new discovery reveals that the rocks also open a uniquely informative window into Earth’s complicated geological history.
Click here for original story, Major North American oil source yields clues to one of Earth’s deadliest mass extinctions
Source: Phys.org