It is the first time that biostratigraphic zonations of calcareous nannoplankton
from Maestrichtian to Lower Tertiary deposits of Iran are reported. The required
samples from the north-eastem and western parts of the country were selected from
the stocks of the National Iranian Oil Company. Taxonomic descriptions were not
the main objectives, although a new species and genus are apparently present in the
assemblages. The main purpose of this study is to establish the biostratigraphic
zonations and correlate them with the universally accepted standard biozones. Both
petrographic and scanning electronic microscopes were used in this investigation