BIOSTRATIGRAPHY OF THE MISHRIF FORMATION FROM WELL AMARAH-1 SOUTHEASTERN IRAQ

Abstract

The fossils of the Mishrif Formation for well Amarah-1 in southeastern Iraq was studied, where 312 thin sections have been used for litho-and biostratigraphic studies. Two biozones have been distinguished within the studied succession; these are from older to younger:1- Praealveolina cretacea partial range zone2- Praealveolina tenuis range zoneAccording to these zones, the age of formation was Late Cretaceous (Cenomanian – Early Turonian). Microfacies analysis showed six environmental indicative facies associations within the Mishrif carbonate platform; these are: deep open marine, shallow open marine, shoal barriers environment, rudisted barriers, back barrier and restricted marine environments.