Abstract

The Sargelu Formation (Middle Jurassic) is very widespread in Iraq and neighboring states. This paper will address two portions of the formation, Barzewa and Barsamarin, which are found within the Erbil Governorate, in northern Iraq. The main objective is to study the mineralogical make-up, geochemical features, and setting up of the Sargelu Formation. These sections gave 21 carbonate component samples that were examined through the use of X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and Scanning Electron Microscopy (SEM). Findings demonstrate that the significant mineral constituents include calcite, dolomite, quartz, and clay minerals, with carbonate minerals mainly comprising euhedral and anhedral calcite and dolomite. Geochemical analysis reveals an Al2O3/TiO2 ratio of 17.39, suggesting an intermediate source rock composition. The depositional environment of the Sargelu Formation is interpreted as shallow marine to marine on sea ramps, based on the V vs. Al2O3 diagram and the presence of coccoliths observed under SEM. Coccoliths, which are abundant in the sunlight zone of the ocean, confirm the marine origin of the deposits. This paper gives a comprehensive description of the Sargelu Formation, with its mineralogical and geochemical features that are essential to learn about its formation history and its future prospects as a hydrocarbon storage. The results add to the general knowledge about the Jurassic stratigraphy in Kurdistan.