BGS Zone 23 (=UKB19 of Hart et al., 1989)

From Earthwise
Jump to navigation Jump to search

Base: Inception of Bolivinoides draco miliaris and B. sidestrandensis.

Top: Inception of Bolivinoides peterssoni.


  • Heterohelix complanata has its inception at the base of the zone.
  • Reussella szajnochae szajnochae occurs in flood proportion immediately below the Maastrichtian.
  • A number of species become extinct at the upper boundary of the foraminifera zone, including Reussella szajnochae szajnochae, Neoflabellina rugosa, Gavelinella monterelensis, Globorotalites hiltermanni and Osangularia cordieriana.

Macrofaunal correlation: upper B. mucronata Zone (= Paramoudra Chalk of East Anglia)

Age: Latest Campanian