Early cretaceous microfossils associations (foraminifera, ostracoda, calcareous algae, and coral) from the Garagu Formation, Duhok Area, Kurdistan Region, Northern Iraq (original) (raw)

Microfossils from an outcrop of the Garagu Formation at Gara Mountain, Duhok Governorate, Kurdistan Region, Northern Iraq, indicate a shallow marinewith normal to hypersaline conditions, shelf lagoonal environment, and open platform. Twenty samples were collected from unbroken succession of the Garagu Formation. The thickness of the succession is 90mand it consists mainly of different colored limestone beds with different fauna contents. The lower boundary with a gradational and conformable nature is with Chia Gara Formation (Tithonian-Berriasian) and the upper boundary is gradational with Sarmord Formation (Valanginian- Aptian). The microbiota associations are mostly composed of species of foraminifera, ostracods, calcareous algae, and coral, with dissociated elements and skeletal fragments of gastropods, pelecypods, bryozoans, sponge spicules, crinoid debris, and echinodermata spines. Sixty species are recorded in this study; the combined stratigraphic ranges of the microfossil species identified from the studied section of the Garagu Formation support an age determination of the Late Valanginian-Barremian.