Paleocene-Eocene Calcareous Nannofossil Biostratigraphy and Cyclostratigraphy From the Neo-Tethys, Pabdeh Formation of the Zagros Basin (Iran)

Sedimentology and sediment geochemistry of the pelagic Paryab section (Zagros Mountains, Iran): implications for sea level fluctuations and paleoenvironments in the late Paleocene to middle Eocene

“…The Paryab section sediments have TOC contents of 0.17-0.58 wt% that are lower than the average shale value of 0.8 wt% (Mason and Moore 1982) and CaCO 3 ranging from 40.5 to 79.5 wt% (for details on carbonate values, see Azami et al 2018). The TOC profile indicates little variation throughout the analyzed section, but in the lower part of the section, TOC contents are lower than in the upper part of section to 142.6 m. Above 142.6 m to top of the section, TOC content decreased again (Fig.…”

“…The studied strata at the Paryab section (N 33°15′14″, E 46°37′3.2″) (Fig. 1) in the Zagros basin includes finegrained pelagic sediments from the uppermost middle to the upper Paleocene (Selandian-Thanetian, nannofossil zones CNP8 and NP6, respectively) to the middle Eocene (Lutetian, nannofossil zones CNE8 and NP14), an interval of around 10 to 11 myr as reconstructed using cyclostratigraphy by Azami et al (2018). In the study area, the gray shales of the Gurpi Formation are overlain by the basal purple shale unit of the Pabdeh Formation (Fig.…”

“…Above this reddish to gray shaly lower part, a prominent interval of limestone-marl cycles of the upper part of the Pabdeh Formation follows and is succeeded by the overlying limestones of the Asmari Formation of mainly Lutetian age. Lithology, cyclostratigraphy, and calcareous nannofossil biostratigraphy have already been studied for the Paryab section by Azami et al (2018), including a high-resolution study for the PETM interval (Azami et al 2018).…”

“…Carbonate content and total organic carbon (TOC) In this study, 179 sediment samples were chosen from outcrops of the Pabdeh Formation in order to measure the TOC and CaCO 3 contents. The carbonate content of all samples (Azami et al 2018) was measured by using diluted hydrochloric acid (error range of 1 wt% CaCO 3 ) and correlated to contents of total organic carbon (TOC), determined at 550°C using a LECO carbon analyzer (Departme nt of Environmental Geosciences/EDGE, University of Vienna, Austria). Samples were analyzed in duplicates or in triplicates if double measurements were above a relative standard deviation of ±5 wt% 2.9.…”

“…This carbon isotope Fig. 6 X-ray diffraction patterns of the clay fraction of samples PB-7B (A) and PB-27 (B) saturated with Mg (green), K (red), Mg and glycerol (MgGly, blue), and K and ethylene glycol (KEG, magenta) and heated to 550°C (KT, black); C X-ray diffraction patterns of some selected bulk samples from the Pabdeh Formation, Paryab section; d values in Å excursion (CIE) coincides, according to nannofossil biostratigraphy, with the PETM interval (Azami et al 2018). This initial rapid negative carbon isotope excursion is typical of continuous PETM sections.…”