Refining The Date Of Dinosaur Extinction And The Cretaceous-Tertiary Boundary

Thanks to a new calibration of the versatile argon-argon dating technique, geochronologists have established a more precise date for the dinosaur die-off at the end of the Cretaceous period: 65.95 million years ago, give or take 40,000 years. This improves on the previous date of 65.5 million years plus or minus 300,000 years, but more importantly, brings argon-argon dating into agreement with other dating methods.