Shallow-marine carbonates were deposited in Central Iraq during the Late Campanian-Maastrichtian. These carbonates consist of foraminiferal- shoal and bryozoan-algal-rudist bank deposits, separated by argillaceous, oligosteginal wackestones and mudstones. The build-ups are believed to have developed on block-faulted topographic highs, while marly limestones were deposited in the intervening basinal lows. Based on facies analysis and log characteristics, these sediments are here divided into eight lithostratigraphic units. Recent exploration activities suggest that Upper Cretaceous carbonates represent a promising petroleum ＇＇play＇＇ in Central and West Iraq, areas in which oil has not previously been discovered These carbonates differ from those in their type locality in southern lung, and in Central Iraq are assigned to the Hartha Formation. The shallow-marine carbonates of the Hartha Formation have produced oil from a well in western Iraq, and good oil shows were also indicated in the Last Baghdad and Ahdab oilfields.