The main objective of this study was to evaluate heavy metal contamination in volcanic and calcareous soils within Morocco’s semi-arid regions, focusing on the relationship between unique soil types and contamination dynamics. Using Geographic Information Systems (GIS), statistical analyses, and several pollution indices, including the Geoaccumulation Index (Igeo), Enrichment Factor (EF), Contamination Factor (CF), and Pollution Load Index (PLI), the research integrates physical and chemical properties to uncover the interactions driving contamination. A total of 64 soil samples from volcanic and calcareous origins, collected at a depth of 20 cm, were analyzed for properties such as organic matter, calcium carbonates CaCO₃, pH, electrical conductivity, and texture, and four heavy metals (Cu, Pb, Zn, and Fe). Findings reveal distinct contamination patterns: calcareous soils had elevated pH, high CaCO₃ levels, and moderate salinity, whereas volcanic soils were more acidic, with higher organic matter content and lower salinity. The contamination indices revealed that all soil samples exhibited some level of contamination, with Zn and Fe concentrations in volcanic soils showing moderate to high pollution levels, while calcareous soils generally displayed lower contamination. The Igeo and CF indices confirmed moderate to high contamination in volcanic soils, particularly for Zn and Fe, whereas calcareous soils showed minimal pollution. The EF analysis indicated slightly higher enrichment for Cu and Zn in calcareous soils than in volcanic soils. The PLI values for both soil types were below 1, suggesting low pollution levels overall. Statistical analyses demonstrated that contamination was shaped by soil characteristics like texture, organic matter, and pH, with anthropogenic sources contributing to heavy metal presence. This study provides new insights into the interaction between soil properties and contamination dynamics in contrasting soil types, revealing that volcanic soils are more prone to heavy metal accumulation due to their physicochemical characteristics. By integrating pollution indices and robust statistical approaches, this work highlights the influence of soil geochemistry on contamination patterns and offers valuable information for informing sustainable land management strategies in vulnerable semi-arid regions.