Ostracoda and benthic foraminifera of Tertiary sequence of western part of İstanbul

Abstract

The samples, derived from the various drillings located at the western part of the İstanbul, were examined systematically and ostracod assemblages were evaluated. Pliocene-Late Miocene and Oligocene-Late Eocene aged sediments have been observed from the top the bottom at the 5 drilling holes. The first drilling hole (Jawa tank), is situated in the north of Merfer in Bakırköy basin, has 163.00 m thickness. The determined ostracod and benthic fauna of this drilling are found between Late Miocene and Oligocene-Late Eocene. Secondly, the samples belonging to the two drilling holes located at the western part of Bakırköy basin (surroundings of Ataköy) were carefully analyzed. The sequence is in Pliocene, Late Miocene and Late Eocene age, and has 292.00 m thickness at this drilling; in addition; the other drilling, representing only Late Eocene according to the ostracod and benthic foraminifera, is 210.00 m thickness in this region. Finally, there are two drilling holes 400 m eastern part of the Jawa tank. Both of the drilling holes are 175.00 m thickness; and the number one has Pliocene age, in accordance with ostracod and benthic foraminifera content, also, the number two is found Late Miocene and Late Eocene age interval. In this study, age and environmental changes of Tertiary sequence located in the western part of İstanbul were investigated depending on the ostracod and benthic foraminifera.