Dinoflagellate Cysts and Miospores from the Albian - Cenomanian Sequence of the Qarun 2 - 1 Borehole, Western Desert, Egypt

Abstract

Rich distinctive dinoflagellate cyst assemblages together with significant numbers of miospores were recovered from seven cuttings samples in the Qarun 2 - 1 borehole between 2718 - 2854 m. This association represents a ? Middle / Late Albian to Early Cenomanian microflora deposited in a nearshore restricted marine or brackish water lagoonal environment. Paleozoic palynomorphs have been isolated from samples dominated by forms of Albian - Cenomanian age. The low abundance, clearly different colour and mixed ages (pre-Early Ordovician acritarchs assigned to Vulcanisphaera sp. at 2738-2740 m and post -Late Ordovician spores) indicate that ? Paleozoic reworking can be easily identified in the mid Cretaceous deposits. The significance of this apparent mixing of assemblages is discussed.