Stratigraphy of the Tayarat Formation (Upper Cretaceous) in Selected Wells, Western Iraq

Abstract

The present investigation deals with the litho- and biostratigraphy of the Tayarat Formation (Upper Cretaceous) from five subsurface sections in Western Iraq. The studied formation composed lithologically of limestone, sometimes dolomitized. The benthonic foraminifera recorded from the Tayarat Formation permit the recognition of the following zones from base to top:1-Orbitoides tissoti-Orbitoides medius Zone.2-Orbitoides apiculatus Zone3-Lepidorbitoides socialis – Lepidorbitoides minor Zone.4-Pseudochrysalidina conica – Pseudolituonella reicheli ZoneThe present investigation indicates that the Tayarat Formation is Late Campanian-Late Maastrichtian in age.