Stratigraphy and Nannofossil Biozonation of Sarmord Formation on the Qaywan Anticline in Sulaymaniyah Governorate, Northern Iraq
The Sarmord Formation is one of the overlooked formations that require more investigations than that achieved before. There are many problems in its definition, age, stratigraphy and aerial distribution. Previously in most parts of the Sulaymaniyah, it is not mapped and its outcrops combined with Balambo Formation while in the present study it is differentiated, mapped in the field on the Qaywan anticline and its problems discussed in details with a suggestion of solutions. For laboratory studies, 31 samples are taken on the Qywan Mountain (anticline) at 23 km north of the Sulaimani city for nannofossils biozonation. This study identified 19 species of the recorded calcareous nannofossils, the studied section reveals three biozones arranged from oldest to youngest as follows: Cretarhabdus loriei Interval Biozone, Lithraphidites bollii Interval Biozone, Micrantholithus hoschulzii Interval Biozone. These nannobiozones are correlated with other calcareous nannofossils biozones from both local and regional sections leading to conclude the age of Late Valanganian to Barremian.