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Abstract The suitability of magnetic parameters as a pre-liminary tool for anthropogenic heavy metals’ (HMs) pollution assessment is proved and supported by many published studies. However, the extent to which this method is effective in an area of complex setting and the way that magnetic signals will be affected are still not well-known. This study aims for HMs pollution assessment in Abu Zaabal area and its vicinities, to understand how the natural geogenic input and interfering land-use affect the magnetic signals, and the viability of magnetic proxy tool to detect and assess HMs pollution in such complex areas. The study area is located south-east Nile Delta that was partly flooded before the High Dam construction where agricultural, residential (urbanized and reclaimed lands), and various industrial activities are interfering. It is one of the most polluted areas in the Nile Delta. Its location encouraged a spatial grain size gradation, which was supported by grain size analysis, from fine (silt and clay) in the north and west to coarser sand in the east and south. Field work (in-situ magnetic measurements and sampling), land-use mapping, grain size analysis, magnetic measurements and other calculated parameters (χ, χfd%, κT, XARM, and S-ratio), magnetic and geochemical mapping, risk assessment indices calculations (CF, EF, Igeo, and PLI), and statistical analysis were conducted to achieve this purpose. A total of 72 surface soil samples were collected to represent the different soil types and land-uses. In addition, 18 sites were selected for core and/or subsurface sampling. On the other hand, both in-situ bulk magnetic susceptibility (κ), measured at 170 sites, and mass specific susceptibilities (χ) show a distribution that corresponds to lithology where they were high in silty and clayey soil in the north and west and low in the other sandy parts. However, strong signals are recorded in sandy areas in the middle, and SE around the main industrial sites; the old steel factory, lead factory, and Akrasha area. Besides, the vertical profiles of χ along with frequency dependent susceptibility (χfd%) in these areas show the ideal distribution of industrial fly-ash. The thermomagnetic runs (κT) revealed that magnetite and titanomagnetite are the dominating magnetic phases that controls the magnetic signal in most of samples. The S ratio-300mT with mean value 0.92 (surface soil samples), indicates a substantial portion of hematite or goethite while S ratio-100mT with mean value of 0.72 indicates that not all the present magnetite is soft (MD)but it is of mixed origin of anthropogenic and natural sources. |