A late Cenomanian-early Turonian interval (Hamam-ghaleh section) adjusted with the transition of Aitamir and Abderaz formations has been investigated in the east of Koppeh-Dagh Basin to examine geochemical anomalies and environmental perturbations related to the oceanic anoxic event 2 (OAE2). The study succession is composed of dark gray shale and glauconitic sandstone of Aitamir Formation, which is conformably overlain by cream marl and marly limestones of Abderaz Formation. The dark shale of the upper Aitamir Formation indicate higher organic matter concentrations especially in the two intervals at the end of Rotalipora cushmani biozone and at the middle part of Whiteinella archaeocretacea biozone. These intervals are characterized by higher detrital input (quartz and feldspar) and chemical alteration (high kaolinite/illite ratios), which suggest a warm-humid condition coeval with high productivity during the OAE2. The Aitamir Formation also shows higher total sulfur (TS) values associated with deposition of framboidal pyrite reflecting an oxygen deficiency, which provided favorable condition for reduction of sulfate. The warm and humid periods in the study section were followed by the cooler and drier intervals associated with decreased TOC values and chemical weathering. These cooling periods might be caused by falling of atmospheric CO2 due to large amount of carbon burial in sediments and high silicate weathering. The δ13Corg positive excursions of around 1‰ are other characteristics of these cooler-drier intervals, which were result of high burial of light carbon (12C) in the organic matter and lower isotopic differentiation in low atmospheric pCO2. At the top of study section, decrease of TOC and TS contents, low detrital input, decreased chemical weathering, and recovery of carbon isotope profile to the lower values indicate that the environmental conditions had returned to the normal oxygenated sea water after the OAE2

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