A recent study has revealed hidden geomagnetic reversals in the Earth’s magnetic history using advanced statistical modeling techniques. Researchers from the University of Tokyo and the Geological Survey of Japan used fixed-bandwidth kernel density estimation (KDE) to uncover previously undetected geomagnetic transitions.
The study found four previously unknown geomagnetic polarity reversals, named the Lima-Limo reversals, in Ethiopian flood basalts dated to approximately 31 million years ago during the Oligocene epoch. These findings suggest that additional undetected reversals may exist in the Earth’s magnetic history.
Using fixed-bandwidth KDE, researchers were able to capture finer details in the geomagnetic record and detect short-lived reversals that were previously missed or averaged out by adaptive-bandwidth KDE models. This approach ensures that subtle variations in reversal frequency are preserved, allowing for a more accurate representation of the Earth’s magnetic field evolution.
The discovery of the Lima-Limo reversals has refined our understanding of the Earth’s magnetic history and challenged earlier assumptions about long periods of stable magnetic polarity. The study suggests that these extended periods may contain unrecognized reversals, requiring further paleomagnetic analysis to uncover hidden transitions.
The use of fixed-bandwidth KDE has demonstrated its potential as a powerful tool for identifying subtle features in geomagnetic records, enhancing our ability to reconstruct the Earth’s magnetic field behavior over millions of years.
Source: https://watchers.news/2025/02/05/hidden-geomagnetic-reversals-found-in-earths-magnetic-history