Fig. 4From: Paleoenvironmental changes across the Paleocene–Eocene boundary in West Central Sinai, Egypt: geochemical proxiesVertical variation in the redox proxies (V/Cr, V/V + Ni and Mn*) and the concentrations of productivity proxies (Porg. and Babio). The vertical variations in V/Cr and V/V + Ni reveal that the DQB sediments were deposited under dysoxic to anoxic bottom conditions. The positive excursion in the Porg immediately above the dark grey shales demarcating the P–E boundary suggests increased primary productivity. The lithostratigraphic units and calcareous nannofossil biozones are shown in Fig. 1Back to article page