Mount Vesuvius eruption used to improve geological dating precision

Researchers from the Berkeley Geochronology Center, UC Berkeley, and the University of Padua have significantly improved the precision of argon-argon dating by using the historical eruption of Mount Vesuvius as a benchmark. By utilizing the detailed eyewitness accounts of Pliny the Younger regarding the 79 CE eruption, scientists were able to calibrate the radioactive dating method with unprecedented accuracy.

Applying the recalibrated method to sanidine minerals from Vesuvius, the team estimated the eruption occurred approximately 1,938 years prior to their 2025 analysis, which aligns closely with the historically recorded date. This breakthrough provides a nearly twofold improvement in the precision of the potassium-40 decay constant.

The enhanced dating method offers broader applications for geologists, paleontologists, and archaeologists. It allows for more accurate timelines for volcanic events in populated regions and serves as a vital tool for ground-truthing other methods, such as carbon-14 and uranium-lead dating, across various geological timescales.