Palynofacies and paleoenvironment of the Early Cretaceous deposits in the Koppeh-Dagh Basin, Iran
Palinofacies y paleoambiente de los depósitos del Cretácico temprano en la Cuenca de Koppeh-Dagh, Irán
Fariba Foroughi1,* , Saeed Maleki2,* , Elnaz Lesan–Khosh1, Sepideh Babaee1, Ebrahim Ghasemi–Nejad1,✝
1 Department of Geology, Faculty of Sciences, University of Tehran. Azar St, Tehran, 16, Iran.
2 Histoire Naturelle de l’Homme Préhistorique, Muséum national d’Histoire naturelle. 57 Rue Cuvier, 75005 Paris, France.
* Corresponding author: (F. Foroughi) This email address is being protected from spambots. You need JavaScript enabled to view it. (S. Maleki) This email address is being protected from spambots. You need JavaScript enabled to view it.
How to cite this article:
Foroughi, F., Maleki, S., Lesan-Khosh, E., Babaee, S., & Ghasemi–Nejad, E. (2026). Palynofacies and Paleoenvironment of the Early Cretaceous deposits in the Koppeh-Dagh Basin, Iran. Boletín de la Sociedad Geológica Mexicana, 78(1), A010825. https://doi.org/10.18268/BSGM2026v78n1A010825
Manuscript received: June 26, 2025. Corrected manuscript received: July 21, 2025. Manuscript accepted: July 31, 2025.
ABSTRACT
We used the palynomorphs from the Early Cretaceous deposits in the Koppeh-Dagh Basin in the Neo-Tethyan province of northeastern Iran to investigate the site’s paleoenvironmental conditions and depositional settings. The AOM–Phytoclast–Palynomorph (APP) ternary diagram highlighted three distinct palynofacies: Type I, II, and IVa. We can accordingly conclude that the depositional environments of the basin included a highly proximal shelf, a marginal basin, and a shelf-to-basin transition. Palynofacies analysis of the Sarcheshmeh and Sanganeh formations of the Koppeh-Dagh Basin revealed that the two formations were deposited in a shallow marine setting characterized by conspicuous input of plant material from nearby land. By comparing these results with those from adjacent sections, two paleoenvironmental trends are present in the Koppeh-Dagh Basin: the eastern side was more turbulent, and the western side was quieter. A previous calcareous nannofossil analysis from the section has been used to date the studied interval of the Sarcheshmeh and Sanganeh Formations, indicating a Late Barremian to Late Albian age.
Keywords: palynofacies, Cretaceous, Koppeh-Dagh Basin, Sarcheshmeh Formation, Sanganeh Formation, Iran.