Mantelliceras mantelli Zone
Base: Base of the zone is mostly coincident with the base of the Chalk Group, except where earliest Cenomanian deposits comprise glauconitic sandstones (eg. locally in South-east Devon), where it is within the highest part of the Upper Greensand Formation.
Top: The top of the zone is immediately below the first appearance of Mantelliceras dixoni (Gale, 1995).
Range of Index species: Common in nominate zone, rare in overlying M. dixoni Zone (Wright & Kennedy, 1984).
|I. crippsi (locally abundant)|
|Mantelliceras spp. (except M. dixoni)|
|Schloenbachia spp. (locally abundant)|
Faunal abundance & preservation: Typically rich and phosphatised fauna near base of zone.
Bio-markers: (see under subzones)
Subzones: Mantelliceras saxbii
Age: Early Cenomanian