via PNAS, 16 March 2021: A new paper in PNAS outlines how the earth’s magnetic field changed during the 12-14th centuries, as reflecting in the iron-smelting site of Tonle Bak in Cambodia.
Extensive spatial and temporal distribution of high-quality data are essential for understanding regional and global behaviors of the geomagnetic field. We carried out chronological and archaeomagnetic studies at the Angkor-era iron-smelting site of Tonle Bak in Cambodia in Southeast Asia, an area with no data available to date. We recovered high-fidelity full-vector geomagnetic information from the 11th to 14th century for this region, which fill gaps in the global distribution of data and will significantly improve the global models. These results reveal a sharp directional change of the geomagnetic field between 1200 and 1300 CE, accompanied by an intensity dip between 1100 and 1300 CE. The fast geomagnetic variation recorded by our data provides evidence for the possible existence of low-latitude flux expulsion. Related discussions in this paper will inspire a new focus on detailed geomagnetic research in low-latitude areas around the equator, and exploration of related dynamic processes.
See also:
- Thousand-Year-Old Furnace in Cambodia Shows How Earth’s Magnetic Field Shifts | Inside Science, 09 March 2021
- TO PREDICT A CATACLYSMIC FUTURE, SCIENTISTS EXPLORE EARTH’S GEOMAGNETIC PAST | Inverse, 11 March 2021
