A Study of Geochemistry, Mineralogy, and Fluid Inclusions on Gypsum and Salt Accompanied with the Introduction of Globerite and Sassolite Minerals in Dehkoyeh, Karmostaj, and Paskhand Salt Domes in Larestan

In the study were analyzed the salts of Dehkoyeh and Karmostaj salt dome(separated based on color), and gypsum of Paskhand salt dome in Larestan region in Fars Province, which is performed in Iran for the first time. The discovery of Sassolite (B(OH)3) and Globerite (Na2Ca(SO4)2) salts (reported in Hormuz Salt Formation for the first time) following mineralogical studies confirm the efficient role of seabed fumaroles in Hormuz salt formation during Infra-Cambrian time. According to geochemical study, strontium is the most abundant trace element and with anhydrite and gypsum. Generally, iron has put the greatest impact on the changes of salt color from among all the elements. In gypsum, salinity changes between 9.7 wt% to 25.3 wt% of NaCl and homogenization temperatures vary between 78.5°C to 230°C. On this basis, Through the study of fluid inclusion data in the Sassolite and Globerite (Na2Ca(SO4)2) minerals, high temperature of 50°C to 60°C were identified. gypsum formation has probably occurred as a result of a secondary process and non-sediment (hydrothermal) processes. The high-temperature fluid has probably originated from the primary evaporative basin as a result of submarine hot solution (fumarole) activities forming the evaporative basin salts. In all probability this fumarole of suppliers ions needed was salt formation and the emergence of large volumes of Hormuz in a relatively short time to justify their salts.