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Detailed geological field investigations have been done at Jabal Sanam structure Southern Iraq. More than 150 rock and mineral represented samples were collected, and 130 thin sections of these samples were prepared and examined microscopically. An accurate mineralogical study of these rocks by analysis of 15 samples with the X-ray diffraction technique was achieved. A large number of sedimentary rocks were distinguished through field observations and petrographic studies, such as gypsum, limestone, dolomite, red and green marl, sedimentary ironstones, chert, and salts. Various types of igneous and metamorphic rocks such as dolerite, schist, slate, and metamorphic sediments were found as beds or fragments intruded with the evaporite rocks of Jabal Sanam. Distinct mineralizations of hematite, pyrite, and dolomite minerals were observed in these successions. It was noted also, that these rocks were subjected to varied geological processes of different degrees that affected their original rock characteristics such as diagenesis, metamorphism, deformation, and dissolution processes. A petrological, stratigraphic, and tectonic correlation has been made with similar structures spread through the region (Iran and Arabian Peninsula) in the light of their composition which, in general; consists of infra-Cambrian evaporates of Hormuz Series. This study supports the previous geological studies on this salt structure, shows a great similarity between the rocks of Hormuz Series Complex and those of Jabal Sanam, which may be considered in terms of stratigraphy and petrology as equivalent rock units. Thus, these rocks may be suggested as the oldest rocks exposed above the earth’s surface in Iraq

The Jabal Sanam, a piercement salt plug, represents a unique geological phenomenon in southern Iraq. It is a remarkable geological landmark that rises about 141 m above sea level and covers approximately 2 km2, surrounded by flat areas on all sides. A radiological survey was conducted on the Jabal Sanam structure to determine the natural radioactivity levels and related radiation hazard indices. Eleven different rock types from several locations at Jabal Sanam were collected. An optical microscope and X-ray diffraction (XRD) were used to examine and identify the variable rock types in this structure. Natural radioactivity using field and laboratory equipment for these rocks was measured. The findings indicated that the average activity concentrations of the 226Ra, 232Th, and 40K radionuclides of the Jabal Sanam rocks are 6.5 Bq kg−1, below the minimum detectable activity (MDA), and 83.3 Bq kg−1, respectively. The average radium equivalent (Raeq) activity value of the investigated rocks is 12.87 Bq kg-1, below the world recommended rate of 370 Bq kg−1. Moreover, the average absorbed dose rate (Dg) is 6.51 nGy h-1, less than 60 nGy h-1. Furthermore, the average values of the external (Hex) and internal (Hin) hazard indices are 0.035 and 0.052, respectively, which are also lower than the allowed limit value of 1.0 set by the international agencies. Overall, the findings of this investigation conclude that Jabal Sanam rocks do not have a radioactive health hazard.

The Zubair Formation was selected in the X oilfield to determine the tar zones via core, and wells logs including micro-resistivity and NMR. The study focused mainly on the main pay of the Zubair Formation, which contains a thick variable tar mat interval near the oil-water contact area, and it impacts reservoir productivity. Tar mat zones were distinguished using different paradigms such as descriptions of core and study borehole logs behavior. The result indicated that the tar mat thickness increases in the middle part of the X oil field due to the presence of high amounts of shale volume. Therefore, tar mats create barriers between oil columns and formation water, preventing the production of secondary oil in these regions.

Mukdadiya Formation represents one of the formations that cover a huge area of Iraq. It contains several clastic deposits, such as sandstone, siltstone, and a noticeable amount of gravels. The gravels are considered as the hallmark to differentiate between Injana and Mukdadiya formations. Therefore, the current study focused on these facies to determine the petrography, paleontology , and origin of Mukdadiya deposits. The results of SEM-EDX and XRD analyses showed two types of gravels, namely the siliceous and lime gravels. The highest percentage of gravels belonged to the sedimentary origin (limestone). The elements of Si, Ca, and Fe represented the common elements that formed the studied gravels. The paleontological study displayed numerous fossils that are composed of these gravels, belonging to several groups, including foraminifera, radiolaria, dinoflagellata, echinoida, gastropoda, and calcisphera.  Also, four microfacies were identified in the studied gravels. After comparison of all collected data with selected formations, the results confirmed that the origin of the derived gravels is from the Qulqula Formation, because of their content of radiolaria and the other characterizing fossils.