There's a test for this: there must be an unconformity exactly
under the K-Pg boundary glauconite.
I should have read on! There _is_ one in that very core:
"The absence of an Ir anomaly at the KT boundary is due to a hiatus that
spans the lower Danian (lower part of Pla) and probably the uppermost
Maastrichtian interval."
At the end of page 2, Keller assumes a drastic spike in Deccan volcanism
right at the boundary. This is strange, as is the absence of any temperature
change at the same time in the same picture. I've never read about this
anywhere... and Keller herself doesn't tell it either, at least not on this
or the next page.