Fig. 2.

(A) Simplified stratigraphy of the BT showing the stratigraphic location of the dated samples. Adapted from ref. 16. (B and C) The (B) plateau and (C) isochron dates produced by single sanidine incremental heating, which are equivalent for all crystals. A weighted mean calculated from all of either the plateau or isochron dates yields a high MSWD, indicating neither is a geologically meaningful age for the Bishop Tuff. Error bars are 2σ analytical uncertainties. (D) Probability density curves for the plateau and isochron dates illustrating that the populations are highly similar.