Figure F10. Residue in the >63-Ám fraction shows rapid increase at the Cretaceous/Paleogene (K/Pg) boundary indicating improvement of planktonic foraminiferal preservation. This implies rapid deepening of the CCD at the K/Pg boundary. The carbonate content record shows that precessional cycles are replaced by eccentricity cycles in the early Paleogene. VPDB = Vienna Peedee belemnite.