Late Cretaceous palynology and paleoenvironment of the Razzak-3 well, North Western Desert, Egypt

Palynological analysis of the Bahariya and Abu Roash Formations from the Razzak-3 (RZ-3) well, North Western Desert, Egypt, has yielded rich and very-well-diversified spores, pollen and dinoflagellate cysts which allow subdividing the studied rock units into four pollen/spore (PS) zones and three dinoflagellate cyst (D) zones. Miospores are abundant in the Cenomanian, while dinoflagellates predominate the Turonian-Santonian. A barren interzone delineates the oceanic anoxic event 2 and embraces member “F” of the Abu Roash Formation. The marine/nonmarine palynomorph ratio in the studied samples indicate that the Bahariya Formation was deposited in a nearshore paleoenvironment affected by continental sources with an arid to semiarid hinterland having local or seasonal humid conditions. Deposition of the Abu Roash Formation took place in the transitional zone between the inner and outer shelf. Dinoflagellate cysts in this study are of the Tethyan Realm.