The 2D electrical resistivity imaging survey was implemented in the area located within the University of Anbar, using a dipole-dipole array to detect the gypsum soil layer. This survey was done along seven analogous 2D lines adjacency in E-W direction, then the data of all 2D lines were merged to produce 3D resistivity imaging models. Laboratory tests of three soil samples in the survey area were analyzed and correlated with data obtained from 2D imaging to determine gypsum content in the soil. Our results of 2D and 3D imaging models show that the gypsum soil layer thickness is 2.53 m approximately, and it is characterized by high differences in the resistivity values in the range of 50 to more than 400 Ωm. This difference is generally caused by high inhomogeneities in the hardness of soil components, while the test results show the gypsum content in the samples equal to 213, 232, and 211 g/kg respectively, and it is indicative of that the soil consists of a high content of gypsum. The correlation between these results is indicative of the area is unstable and can be led to a differential settlement that causes cracks and collapses of the constructions.

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This experimental study presents a comparison between two‐dimensional azimuthal and three‐dimensional electrical resistivity imaging techniques at a given location within the Abu‐Jir Fault Zone, Central Iraq. The aim is to examine which one is a better technique in one order to study the subsurface fracture zones and to use it within and outside the fault zone. Our results show that the two‐dimensional azimuthal imaging technique is quite successful in imaging the structural geology, particularly for effective identification and delineation of the subsurface fracture zones in all directions, whereas the three‐dimensional imaging technique, carried out using data acquired in parallel two‐dimensional imaging lines, gives limited and distorted images about these zones because the Y‐spacing between the survey lines is quite small compared to the length of these lines. The two‐dimensional azimuthal technique can be useful in deep investigations to determine the extent of the structures, particularly in areas with unknown geological and structural settings.

Geothermal gradient is an important tool in petroleum exploration and critical to several reservoir evaluations. Borehole Temperature data from 14 wells are utilized to find the geothermal tendency of the Western Desert in Iraq. The discrepancies in geothermal gradients throughout the area are a consequence of variability of sediment’s thermal conductivity, direction of groundwater flow, fault pattern, and heat generation. High value converts liquid hydrocarbon to dry gas and low value will not help organic matter to reach maturity level. The lowest gradient within the units above Palaeozoic Era’s section is 12.2 °C/km for well KH-9/7 in the eastern part of the area and the highest is 31.3 °C/km for well KH-5/4 in the middle part of the region. Whereas, the highest geothermal gradient which is 61.0 °C/km within the Palaeozoic section is recorded within Akkas Formation in 2100-2350 m subsurface. The mean geothermal gradient in Western Desert is 26 °C/km within the units younger than the Palaeozoic, but this average rises up to 40 °C/km within Palaeozoic units due to existence of Silurian hot shales and heat flow from the Proterozoic section especially from Halaban Group andesites.