Mineralogy and Morphology of Iraqi Sea Salt and Sabkhas

Abstract

A few studies have investigated the morphology and mineralogy of the salt deposits in Iraq. These deposits have amassed in substantial amounts as a result of the rise in temperature, specifically during the summer season. This study aims to analyze and characterize the mineral composition, morphology, and salt crystallization of the sabkhas and sea salt. The physicochemical tests (X-ray Diffraction, X-ray fluorescence, Field Emission Scanning Electron Microscopy, and energy dispersive spectroscopy) were used in this study. Samples were collected from sabkha salts in Diyala, Al-Emara, and the sea salt in Al-Basra. These locations exhibit an important and unique distribution of precipitated salt. The study showed that a semi-arid to arid climate in small pools located in specific locations led to the generation of Sabkhas and sea salt through saltwater evaporation. After processing the samples, the half-and-quarter method was used to obtain a 20-gram sample from the investigated bulk substance. According to the XRD analysis, halite is the main evaporite mineral present in the samples, with calcite, anhydrate, gypsum, and bischofite following it in decreasing order of abundance. The predominant trace elements include sulfur (S), magnesium (Mg), calcium (Ca), aluminum (Al), silicon (Si), iron (Fe), and molybdenum (Mo). Sea salt from the Al-Fao in Al-Basra exhibits exceptional mineral concentration and forms cubic-shaped crystals due to excellent evaporation of seawater. The most common crystallization patterns found in sabkhas and sea salt consist of hopper shapes, cubic crystals, rhombic crystals, cryptocrystals, and tabular shapes. Each of these forms of crystallization occurs at ambient temperatures.