Biostratigraphy and Paleoecology of the Anah Formation in Kurdistan Region, Iraq

Abstract

In the current study, biostratigraphy and paleoecology of the Anah Formation have been investigated.The study area is located in the Sulaimanyah Governorate, Kurdistan Region, Northeast Iraqwhere the Darzila section hasbeen sampled. Twenty-five species of larger foraminifera and skeletal fragments of coral, echinoid spine, pelecypods,and gastropods are described in seven samples collected from the Darzila section. Based on the distribution of the larger-benthic foraminifera andother skeletal grains, two assemblage biozones of the Late Oligocene–Early Miocene age have been recognized. According to the paleoecological parameters,such as temperature, nutrients, depth, and salinity in the study area, the Anah Formation hasdeposited the euphotic zone, abundant imperforate foraminifera are present, sub-tropical waters under oligotrophic to mesotrophic middle ramp environment with normal to a higher salinity inner ramp setting and at water depths that ranged from 40 m to 80 m, anda temperature about 18–25ºC.