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This study examines the effects of land use and slope aspect on soil erodibility (K-factor) and the fractal dimension (D) of soil particle size distribution (PSD) in calcareous soils at the watershed scale in western Iran. The study analyzed 113 soil samples collected from four land uses (slope-farmland, farmland, pasture, and woodland) at a depth of 0–20 cm, measuring common soil properties such as soil texture, soil organic matter (SOM), calcium carbonate (CaCO3), pH, and cation exchange capacity (CEC). The PSD of soil samples was measured using the international system of soil size fractions, and the D for PSD was calculated. The K-factor was calculated using the RUSLE model. The results showed that the K-factor was highest in slope farmlands with SOM at 1.6% and lowest in woodlands at 0.02 Mg h MJ−1 mm−1 with SOM at 3.5%. The study also found that there were significant correlations between D and clay content (r = 0.52), sand content (r = −0.29), and CEC (r = 0.36). Woodland soils had the highest SOM content, with a mean D value of 2.895, significantly higher than the mean D value of slope farmland soils, which had the lowest SOM at 1.6%. The study concludes that woodland soils retain finer particles, particularly clay, resulting in lower soil loss and land degradation compared to other land uses. Finally, the study suggests that shady slope aspects (south aspect) contain more organic matter due to less solar radiation and higher soil water content, resulting in lower soil erodibility (0.02 Mg h MJ−1 mm−1) and higher D values compared to other slope aspects. [ABSTRACT FROM AUTHOR]

Known to be triggered and controlled by tectonic systems, magmatism plays a significant role in the deposition and emplacement of hydrothermal mineral systems. It is, therefore, of paramount importance to recognize the tectonic processes that are genetically associated with hydrothermal mineral systems. This study seeks to address this research gap by recognizing the main tectonic processes that have controlled the distribution of porphyry copper (Cu) deposits in Dehaj Area on the Urmia-Dokhtar magmatic belt, central Iran. For this purpose, spatial associations of 31 known porphyry Copper deposits, faults, and fractures were evaluated by multiple numerical techniques including fry, fractal, (box-counting and radial-density methods), and distance-distribution analyses to investigate structural controls of the porphyry Copper mineralization. Results of the fry analysis revealed three mineralization trends, namely NS, NE, and NW, clearly following the existing fault systems in the area. Application of the fractal method demonstrated that structural controls on mineralization have operated on two different scales, regional and local scales. Distance-Distribution analysis was further used to spatially correlate known porphyry Copper deposits to fault traces, supplementing the results of fry and fractal analyses by quantitative measurements. Compiling the results of these three methods, it was shown that NW-trending faults have plausibly controlled the magmatism on a regional scale. On a local scale, however, NE- and N-trending faults have probably acted to control the channelling and emplacement of mineral-bearing fluids. [ABSTRACT FROM AUTHOR]