Kerogen and Palynomorph Analyses of the Mid-Cretaceous Bahariya Formation and Abu Roash “G” Member, North Western Desert, Egypt

Bahariya Formation and Abu Roash “G” Member sediments in the Razzak Well #7, North Western Desert, Egypt contain abundant kerogen and fossil palynomorphs. In this study, we examined changes in these organic components and use them to interpret paleoenvironmental conditions and biostratigraphy. Terrestrial organic components dominate the Bahariya Formation and basal Abu Roash "G" Member, in particular degraded phytoclasts. Since the dinoflagellate cysts in these units are dominantly peridinioids such as Subtilisphaera, the sediments were likely deposited in nearshore, moderate to high-energy conditions. In contrast, amorphous organic matter and marine palynomorphs are more abundant in the upper part of the Abu Roash "G" Member, suggesting deeper depositional conditions. The overall palynomorph composition is typical of the mid-Cretaceous "African-South American" Province (ASA). There is a noticeable variation in the abundance of certain palynomorph taxa such as Afropollis jardinus and trilete spores, which are fewer toward the top of the Abu Roash “G” Member. This variation may be a reflection of prevailing changes in the wet/dry conditions and sea level rise.