Lithofacies and Nannobiostratigraphy of Fat'ha Formation, Perman Anticline, Northern Iraq

Abstract

A surface section of the Fat'ha Formation (Middle Miocene) was studied in the Shaqlawa area, Erbil Northern Iraq. It consists of Clastic (mudstone), and carbonates (marly, marly limestone and limestone). These sequences variable thickness based on rocky differences. The lower boundary is unconformatiy with Pelispi Formation to founded basal conglomerate. The upper boundary sequence with the Injana Formation is conformable. The sedimentary structures were distinguished in the formation within the Shaqlawa region include, mudstone flaser, lamination and lenses also marly Planar and lamination bedding with sequencec marly limestone planar, thinly to laminated and flaser bedding, wavy laminations stromatolites and limestone thinly, massive bedded.

Calcareous nannofossils assemblages are diagnosed from twenty one samples from Fat'ha Formation at Perman anticline, Northeastern Iraq. The objective of this study is to determine the geologic age of this formation which is detailed investigation is carried out, during which eighteen species of calcareous nannofossils identified. The recorded calcareous nannofossil assemblages include one biozone which are from the section, Helicosphaera ampliaperta Interval Biozone. This biozone is correlated with other calcareous nannofossils biozones from both local and regional sections that lead to conclude the age of the Early Miocene (Burdigalian). Our detailed analysis of the sedimentary succession focuses on the two main lithofacies (siliciclastics, carbonates).