Study of paleoecology and paleoceanographic condition of Khangiran Formation based on the lack of Morozovella (Index genera of Eocene planktonic foraminifera)

Subject Areas :

M.A Salahi ¹ , Mohammad Vahihinia ²

1 - دانش آموخته کارشناسی ارشد چینه شناسی و فسیل شناسی، دانشگاه فردوسی مشهد
2 - استاد یار گروه زمین شناسی، دانشکده علوم، دانشگاه فردوسی مشهد

Received: 2016-09-07 Accepted : 2016-09-07 Published : 2012-12-21

Keywords: Eocene, Kopet-Dagh basin, Khangiran Formation, Morozovella,

Abstract :

Kopet-Dagh basin is located in north and northeast of Iran. Khangiran Formation is one of the most importantformations of Paleogene deposits. For study of Khangiran Formation, Chehelkaman Syncline section wasselected. This section located in southwest of Sarakhs city, east of Kopet-Dagh basin. Thickness of this section is136 meters and lithology of this section composed alternation of olive green Marl and limy yellow Marl. In thisresearch foraminifera fauna of Khangiran Formation was studied. The age of this section is Early-MiddleEocene, and planktonic foraminifera fauna of this section shows anomaly. Based on this anomaly, lack ofMorozovellids, that are index fossils of Eocene, was observed. Eutrophic condition of this Formation as for theplanktonic and benthonic foraminifera study is the reason of this subject that it's the result of changes in thepaleoceanographic conditions such as situation of stratification of water column and nutrient changes. As far theMorozovellids can't accordance with eutrophic condition, lack of the species mans of this genus observed forKhangiran Formation. Khangiran Formation condition is comparable with Caucasus basin and this subject can beindicating of same condition of this two basin at least during the Eocene time.