Ostracods sensitivity to reconstructing water depths and oxygen levels: A case study from the Middle-Late Eocene of the Beni Suef area (Egypt)

Paleoclimate and Paleoenvironment Reconstructions from Middle Eocene Successions at Beni-Suef, Egypt: Foraminiferal Assemblages and Geochemical Approaches

“…The depositional environment was established based on the foraminiferal data, which showed common to moderate occurrences of species belonging to the following genera Cibicides and Lobatula, pointing to an inner to middle shelf environment [99,105], and high abundance of Bolivina spp., which inhabit the outer shelf settings [96,105]. Moreover, the dominance of non-bioturbated and well-bedded limestones (an average of CaCO 3 76.9%) indicates low and calm energy environments, which are identical to outer shelf settings [22,106]. The common to high abundance of the calcareous epifaunal benthic species, coupled with high values of BFOI, point to moderate to high oxygen levels.…”

“…The occurrence of index benthic foraminifers (Bulimina jacksonensis, Nummulites beaumonti), besides small-sized and spinose planktonic foraminiferal species (Acarinina spp., Morozovelloides spp. ), assign this rock unit to upper middle Eocene (Bartonian) [18,19,[21][22][23].…”

“…The exposure of Gebel Qarara (G. Qarara on Figure 1) lies at about 48 km southeast of Beni Suef, at latitude 28 • 37 37.2 N and longitude 30 • 55 29.1 E, whilst that at Gebel El Heiba (G. El Hadid) is located at approximately 34 km southeast Beni Suef City, at latitude 28 • 46 36.9 N and longitude 30 • 57 15.1 E (Figure 1). The detailed lithostratigraphic description and field investigation of the studied exposures allowed us to recognize two rock units from base to top, the Qarara and the El Fashn formations (Figure 2), which were named after reviewing the studies that have been carried out on the Eocene rocks of northern Egypt [15,18,19,[21][22][23][39][40][41][42][43][44][45][46][47][48]. These are briefly discussed and described from older to younger in the following chapter.…”

“…Therefore, geochemical analyses, together with micropaleontological investigations, perform an important role in reconstructing the paleoecologic conditions and constructing models for sea-level changes in response to changing inhabited areas, climate, and sedimentary supply [7][8][9][10][11]. Many authors focused on studying the Eocene strata of Egypt concerning paleontology, lithostratigraphy, biostratigraphy, and paleoecology [12][13][14][15][16][17][18][19][20][21][22][23][24]. Along the broad North African shelf, the middle Eocene rocks of Egypt are exposed in different localities showing distinctive facies changes from carbonates to clastics, all marked by the occurrence of distinctive Southern Tethyan foraminiferal assemblages [18][19][20][21][22][23][25][26][27][28].…”

“…Many authors focused on studying the Eocene strata of Egypt concerning paleontology, lithostratigraphy, biostratigraphy, and paleoecology [12][13][14][15][16][17][18][19][20][21][22][23][24]. Along the broad North African shelf, the middle Eocene rocks of Egypt are exposed in different localities showing distinctive facies changes from carbonates to clastics, all marked by the occurrence of distinctive Southern Tethyan foraminiferal assemblages [18][19][20][21][22][23][25][26][27][28]. Here, benthic foraminifera are more abundant than planktonic foraminifera, so only they can be used for biostratigraphic purposes [19,20,[29][30][31][32][33][34].…”