Abstract

A magnetostratigraphic and biostratigraphic comparison was made between latest Cretaceous to early Paleocene strata exposed in the Red Deer Valley of Alberta and in the Missouri Valley of North Dakota. Extinctions of latest Cretaceous palynomorphs such as Aquilapollenites, taken as the Cretaceous-Tertiary boundary indicator, occur between 0.7 and 1.0 m above the No. 13 (Nevis) coal in the Red Deer Valley, and within 0.2 m of the base of the lowest coal in the Ludlow Formation in the Missouri Valley section. This extinction level occurs in the upper half of reversed polarity zone 29 r in both sections. The exposed lower 40 m of the early Paleocene marine Cannonball Formation in the North Dakota section encompasses part of polarity zone 29 r as well as all of 29,28 r and at least part of 28. Sedimentation rates in the North Dakota section were about two-thirds of those in the fluvial Alberta section.