LAUSR

Surface sediments (n = 124) were gathered to evaluate spatial pattern and source apportionment of ∑24n-alkanes in the Persian Gulf. Moran’s I indices revealed that ∑24n-alkanes were randomly distributed in sampling space in general. One noticeable exception was a significant spatial high-high cluster (Z-score = 8.6). Profile of n-alkanes observed for this cluster maximized at n-C20, n-C18, n-C16, and n-C22. Detection of very low carbon preference indices and strong even carbon-numbered predominance suggested that bacterial inputs were the process making this cluster. Based on diagnostic ratios and GIS techniques, in situ production of organic materials was widespread in the studied space. Allochthonous and petroleum-based inputs were not traceable for 73.8% and 24.7% of the area, respectively. Petrogenic source apportionment map proposed that petroleum-originated contaminants were probably limited to 6.32 km2 of the sampling matrix. The biogenic inputs (autochthonous and allochthonous inputs) and not the petroleum contaminants were the main source of n-alkanes deposited.