An Analysis Of The Ranges Of Globigerinina (Foraminiferida) Genera And Their Bearing On The Cretaceous-Tertiary Boundary

Abstract

An analysis of the Globigerinina genera from the Middle Jurussic to Holocene, using the method of Cutbill & Funnell, indicates that a major break of the Globigerinina genera occurred at the Maastrichtian-Paleocene boundary (loss) and at the Oligocene-Miocene boundary (gain). This break seems to be marked by an abnormally high rate of extinction of most genera followed by an accession of new ones at the Maastrichtian-Paleocene boundary and at the end of the Oligocene.