Fig. 2: Measurement results from coral samples.

\(^{236}\)U/\(^{238}\)U (black squares) and \(^{233}\)U/\(^{238}\)U atom ratio (gray dots) in the Kume coral core as a function of time. The measurement uncertainties shown are ±1 \(\sigma\) (s.e.m.). The data points are connected by solid lines (bold for \(^{236}\)U) to guide the eye. The maximum at 1955 is not statistically significant and thus, not linked to the neighboring points.