Planktonic Foraminiferal Biostratigraphy of Shiranish Formation in Dohuk Area/ Northern Iraq

Abstract

The litho-and biostratigraphy of Shiranish Formation have been investigated within a well-exposed section at the southern limb of Bekhair anticline, Dohuk area, Northern Iraq. The studied section consists mainly of marl, marly limestone, and limestone. The Formation unconformably overlies Bekhme Formation and it is overlain unconformably by the Kolosh Formation. The samples of the section under investigation yielded rich and well diversified planktonic foraminiferal taxa, where 55 planktonic species belonging to 16 genera have been recognized, the detailed foraminiferal investigation permits the recognition of 8 well defined zones. These are from older at the base: 8. Plummerita hantkeninoides Total range Zone (Part). 7. Pseudoguembelina palpebra Partial range Zone. 6. Pseudoguembelina hariaensis Interval Zone. 5.Racemiguembelina fructicosa Interval Zone. 4. Planoglobulina acervulinoides Partial range Zone. 3. Contusotruncana contusa Interval Zone. 2. Gansserina gansseri Interval Zone. 1. Globotruncana aegyptiaca Interval Zone (Part). The Planktonic zones were correlated with other zonal schems in and outside Iraq. They are considered to be extending from middle Late Campanian to latest Maastrichtian.