Fig. 4.

A high-resolution XRF scan of the transverse section of GOR-76 featuring an unusual depletion of the element Ca. The mapped area was identified as the only significant elemental anomaly in the 16th century BC growth rings from this sample (a longer scan area is provided in SI Appendix, Fig. S3). This scan shows that a calcium depletion occurs from around 1562 to 1558 BC and is centered on an unusually wide, slightly pale in color growth ring at 1560 BC. A similar wide, pale ring occurs in 1550 BC but does not indicate the same degree of depletion.