Benthic foraminiferal communities of the Eocene platform, north Eastern Desert, Egypt

Abstract

The Eocene successions on Beni Suef – El Zaafarana road at north Eastern Desert of Egypt have been examined for their benthic foraminiferal contents from three rock units: El Fashn, Beni Suef and Maadi formations. The studied material of this work allowed us to identify 153 benthic foraminiferal species. The Eocene age of the studied successions is defined by the co-occurrence of the planktonic and benthic foraminiferal species. The studied succession could be subdivided into five benthic foraminifera biozones from the late Middle to Late Eocene age. These zones are Palmula ansaryi Range Zone (late Middle Eocene), Bulimina jacksonensis - Uvigerina mediterranea Concurrent-Range Zone, Cancris auricula Lowest Occurrence Zone, Pararotalia audouini Concurrent-Range Zone and Pyrgo elongata Concurrent-Range Zone (Late Eocene). The identified benthic foraminiferal species were analyzed using R- and Q-mode cluster analysis in order to better understand the linkage between the benthic foraminiferal assemblages and paleoenvironmental conditions. The cluster analysis revealed that the benthic foraminifera could be grouped into 7 assemblages and 7 biofacies in the measured sections. The recorded benthic foraminiferal biofacies suggest that the environments are deep outer ramp setting with meso-to moderately eutrophic conditions, and minimum to moderate oxygenation level on El Fashn Formation. The environment of Beni Suef and Maadi formations is inner to middle ramp with high oxygen level and oligotrophic conditions.