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Utilizing aeromagnetic data, this research examines basement rocks in Iraq, focusing on the southwestern part, known as the Southern Desert. The basement has particular importance since it is deep and has not been discovered directly yet. The purpose of this study is to outline regions of remanent magnetization, which have lithological, structural, and tectonic implementations using a recently proposed method by Smith et al. (2022) that transforms the magnetic data to the pole and vertical dip and subsequently estimates the apparent magnetic susceptibility. The results show the presence of remanent magnetization in the basement with different shapes and spatial extensions that predominately aligns in northwest-southeast and north-south directions in accordance with basement inherited weak zones. Further, these occurrences lie in particular tectonic zones and sub-zones. The results in the Southern Desert are consistent with a previous study that used two-dimensional forward modeling and mentioned remanent magnetization in two north-south-trending zones. Concerning the origin of the reversely magnetized bodies in Iraq, their distribution may suggest either faulting in a basement terrane (of reverse magnetization) with different displacement or intrusions of basic rocks within structural basins that are resulting from extensional tectonics.

The Southern Desert of Iraq covers a vast region in southwest Iraq. The stratigraphic column comprises relatively thick sedimentary strata, which overlay a Neoproterozoic basement and dip gently towards the northeast. The ground surface is depicted by intensive karst forms of variable dimensions, especially within carbonate rocks of the Dammam Formation (Middle-Upper Eocene). In the present study, we use the Bidimensional Empirical Mode Decomposition technique for analyzing the gravity field into multi-residual fields and one regional. Analyzing and interpreting the resultant fields utilizing the geological data are the aims of this study. A free download MATLAB code is applied to the gravity data of the Southern Desert which is designed to separate the two-dimensional gridded gravity map into three residual maps and a regional one. These maps may reflect depths at different levels; shallow, intermediate, deep, and near the Moho discontinuity, respectively. According to the available information about the geology of the area, the residual maps can be interpreted in terms of shallow-depth geological structures, which have an economic interest in hydrocarbon exploration, intra-basement structures, and variation in the density of the basement terranes. The regional map, however, is interpreted to be related to a deep-seated gravity source most likely near the Moho. Further, the results illustrate an obvious relation between some of the gravity positives, in the first residual map, and the drilled exploration wells. This suggests a delineation of newly prospected structural highs. In addition, the second residual map shows gravity negatives that probably delineate basement basins/sub-basins.

Utilizing aeromagnetic data, this research examines basement rocks in Iraq, focusing on the southwestern part, known as the Southern Desert. The basement has particular importance since it is deep and has not been discovered directly yet. The purpose of this study is to outline regions of remanent magnetization, which have lithological, structural, and tectonic implementations using a recently proposed method by Smith et al. (2022) that transforms the magnetic data to the pole and vertical dip and subsequently estimates the apparent magnetic susceptibility. The results show the presence of remanent magnetization in the basement with different shapes and spatial extensions that predominately aligns in northwest-southeast and north-south directions in accordance with basement inherited weak zones. Further, these occurrences lie in particular tectonic zones and sub-zones. The results in the Southern Desert are consistent with a previous study that used two-dimensional forward modeling and mentioned remanent magnetization in two north-south-trending zones. Concerning the origin of the reversely magnetized bodies in Iraq, their distribution may suggest either faulting in a basement terrane (of reverse magnetization) with different displacement or intrusions of basic rocks within structural basins that are resulting from extensional tectonics.