Paleocene (SBZ1-4)

SBZ 4 (late Thanetian)
Defined by the biostratigraphic range of : Glomalveolina levis, Hottingerina lukasi, Miscellanea meandrina, Daviesina garumnensis, Dictyokathina simplex, Nummulites catari, Assilina azilensis and Ass. yvettae. The lower boundary is located in the lower part of Chron 25r [Serra-Kiel et al., 1994]. The biozone is correlated to the upper part of NP8 and the lower part of NP9 [Kapellos and Schaub, 1973; Schaub, 1973, 1981], and rides on the P4-P5 boundary [Hillebrandt, 1965 in Schaub, 1969; Hillebrandt, 1975 in Tambareau, 1994; Tambareau, 1972; Tambareau and Toumarkine, 1974; Robador, Orue-Etxebarria and Serra-Kiel, 1991].

SBZ 3 (early Thanetian)
Defined by the biostratigraphic range of: Glomalveolina primaeva, Periloculina slovenica, Coskinon rajkae, Fallotella alavensis, Cribrobulimina carniolica, Vania anatolica, Miscellanea yvettae, Pseudomiscellanea primitiva, Ranikothalia bermudezi, Nummulites heberti and Discocyclina seunesi. The lower boundary imprecise, located in the lower part of Chron 26r [Serra-Kiel et al., 1994]. This biozone corresponds to interval NP5-NP8 [Seyve, 1984 in Tambareau, 1994; Schaub, 1973, 1981] and P4 [Hillebrandt, 1965 in Schaub, 1969; Robador, Orue-Etxebarria and Serra-Kiel, 1991].

SBZ 2 (Selandian)
Defined by the biostratigraphic range of: Miscellanea globularis, Ornatononion minutus, Paralockhartia eos, and Lockhartia akbari. Lower boundary imprecise, located in the upper part of Chron 26r and within P3 according to Robador, Orue-Etxebarria and Serra-Kiel [1991].

SBZ 1 (Danian)
Defined  by the biostratigraphic range of Laffitteina bibensis and Bangiana hanseni. The lower boundary corresponds to the  Cretaceous-Tertiary boundary. This biozone is characterized by the presence of Laffitteina, the only survivor among the Cretaceous complex forms with canal systems.

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith