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The early Miocene Qom Formation is exposed in the Bagh section, northeast Isfahan, Central Iran, where it unconformably overlies Oligocene deposits and is unconformably overlain by the Upper Red Formation. The formation is mainly represented by carbonate deposits (marl, marly limestone facies) and subordinate siliciclastic facies. The planktonic foraminiferal biostratigraphical analysis led to recognition of two main planktonic foraminiferal zones: 1. the Globigerinoides primordius Zone in the lowermost part of the section indicating early Miocene (Aquitanian) and 2. the Globigerinoides trilobus Zone in the upper most part of the Qom Formation of Burdigalian age (early Miocene). Composition and abundance of benthic and planktonic foraminifers were examined for paleoenvironment reconstruction and paleoecology. The Q-mode cluster analysis performed on the benthic foraminifers led us subdivide the section into three distinct benthic foraminiferal clusters: I. the Cibicidoides ungerianus cluster in the lower part of succession, indicating predominantly inner neritic environments; II. the Lenticulina orbicularis cluster in the middle part of section, indicative of middle-outer neritic environments, and III. the Elphidium-Amphistegina cluster recorded in the upper part of the formation and characterizing a typical outer neritic environment. The planktonic foraminifers are interspersed in the upper part of the section with relatively low diversity, indicating open marine shelf segments, whereas the lower part of the section is characterized by an abundance of benthic foraminifers. As a point to consider for paleoecology and paleoenvironment, abundant although with low diversity benthic foraminifera with small tests, and calculated data based on these clusters are indicative of high nutrient and high oxygen environment with normal marine salinity during the early Miocene at the Bagh section.Keywords: Aquitanian, Burdigalian, benthic foraminifera, paleoenvironmental condition. Resumen

Sedimentological and geochemical records are presented for an upper Paleocene to middle Eocene deep-water pelagic succession of the Pabdeh Formation in the Paryab section, Zagros Mountains, NW, Iran. In this study, grain-size statistical parameters, cumulative curves, and bivariate analysis on twenty-five sediment samples were used to decipher depositional processes and paleoenvironments. XRD analysis of the fine-grained silt to clay sediments indicates that quartz, calcite, ankerite/dolomite, and clay minerals such as illite, chlorite, and kaolinite constitute the main minerals within these sediments. Elemental and isotopic chemostratigraphies are used to infer depositional conditions and sea level trends through time. TOC-CaCO3 trends of the samples are used to interpret the type of deposition and sediment accumulation rates, rhythmic bedding, and identification of regressional and transgressional phases. In the studied section, the manganese contents exhibit a declining trend along the lowstand systems tract that terminates in a sea level lowstand and the subsequent start of a transgressive trend. Some geochemical parameters such as Mn values and δ13C contents of sediments along a sequence can be used as potential sea level proxies that are tested in this study. The Paleocene-Eocene Thermal Maximum (PETM) interval of the Pabdeh Formation coincides with increasing Mn contents and Mn/Al ratios. Ti/Al and Si/Al ratios show contrasting trends to Mn values and Mn/Al ratios. Generally, elemental and isotopic results of the Pabdeh Formation confirm the presence of a long-term three-stage sea level cycle in the studied interval that is related to the PETM event. Based on elemental analyses such as Co, Mo, Ni, V, and Cr contents, the Pabdeh Formation sediments were deposited in suboxic to slightly anoxic conditions.