Integrated geological and geophysical approaches to map structural controls of chromite deposits associated with ultramafic–mafic complexes of the Ingasana in the southwestern Blue Nile metallogenic province, SE Sudan

Abstract

The Ingasana Mafic-Ultramafic Complex (IMUC) located in the southwestern Blue Nile region of Sudan, hosts significant chromite deposits of considerable economic importance. Although some preliminary studies have been conducted, however important genetic details, such as integrated geophysical and geological analyses, have not yet been thoroughly investigated. In this study, we conducted a detailed investigation of field features, petrography, and Integrated geophysical surveys in the ore prospect areas of the IMUC for the first time. The aim was to clarify the geological structures and metallogenic characteristics of the region, particularly focusing on the boundaries of rock units associated with chromite deposits. The results from the three-dimensional gravity inversion analysis identify the boundaries between different rock types, including subsurface density variations and major shear zones, revealing that most known mineralization sites are closely associated with structural features and the fault system of the area. Exploratory drill holes (D.H.) of different depths confirm the subsurface occurrence of thin chromite with serpentinite as ven bodies within the ultramafic rocks of Ingasana.On the other hand, Petrological Examinations (P.E.) results identify boundaries between other rocks. These findings further suggest that areas with high-density anomalies are the most favorable for hosting chromium, whereas regions covered with clay rocks exhibit the opposite potential. Furthermore, the study highlights the critical role of fault zones as conduits for magma and mineralizing fluids, emphasizing their significance in controlling the emplacement of mafic–ultramafic rocks and associated mineralization. The integration of geophysical and geological data not only enhances our understanding of the structural framework but also provides a robust basis for future exploration, guiding targeted prospecting efforts for chromite and other related mineral deposits in the IMUC.