Scientists have made a groundbreaking discovery that could revolutionize the field of geological dating. A research team from Germany, Australia, and the US has found an unexpected accumulation of a rare radioactive isotope called beryllium-10 (10Be) in samples taken from the Pacific seabed.
The 10Be isotope decays into boron over time and can be used to date geological archives spanning millions of years. However, current methods have limitations, such as being unable to date samples older than 50,000 years. The discovery of this anomaly offers a new tool for dating even older samples, potentially extending back over 10 million years.
The team analyzed the 10Be content using Accelerator Mass Spectrometry (AMS) and found that the concentration was significantly higher than expected around 10 million years ago. This anomaly may have been caused by changes in ocean currents or astrophysical events, such as a near-Earth supernova or a collision with an interstellar cloud.
The discovery has significant implications for geological dating and could serve as a global time marker. If confirmed, this finding would provide a new way to synchronize data sets from different archives and address the fundamental problem of common time markers in geology.
Source: https://phys.org/news/2025-02-anomaly-deep-sea-accumulation-rare.html