Earth and Planetary Science
EPS Geophysics

MAY 2008 - Pinpointing the dinosaurs' demise

EPS faculty member Paul Renne and colleagues at the Berkeley Geochronology Center, the Free University of Amsterdam, and Utrecht University, are fine-tuning geochronology to unprecedented levels of accuracy. By calibrating the uniquely versatile 40Ar/39Ar radioisotopic dating method with climate proxy signals tracking Earths orbital cycles, the team reported a ten-fold increase in accuracy. As an illustration of the consequences of their study, reported in Science (reprint), the age of the Cretaceous/Tertiary boundary, and the extinction of the dinosaurs, has been adjusted by almost 500,000 years to 65.95 Ma. UC Berkeley news release.