Multifractal model is effective in analyzing local enrichment and desperation of the geochemical elements. Using the method of multifractal model and the local singularity and based on GIS-based Geological Data Analysis System (GeoDAS), we have analyzed the 13 elements of 1 783 geochemical samples collected from fractures in Gaosong ore field of Gejiu. Our results show that the multifractal spectrum function of α-f (α) has an asymmetric and continuous convex curve, suggesting the differential local enrichment for each element, and accordingly they were grouped into main ore-forming element combination (Sn-Cu-Pb-Ag-As-Mn) and associated element combination (Zn-Sb-Cd-W-Mo-Bi-Hg). The changes of variables of T"(1) and Dq defined by multifractal model indicate that Sn has the highest multifractality indices among the main ore-forming elements, followed by Ag, with Cu is the lowest. A good correlation between T"( 1) value and variation coefficient was observed for each element, and the singularity index α for each element has enhanced the information for geochemical enrichment area, and therefore can be used as an important parameter to determine local enrichment. The multifractal approach has an important theoretical and practical significance in revealing local spatial enrichment of minera-lized elements and local singularity characteristics.%多重分形理论能够有效地分析地球化元素局部富集和贫化规律.对取自个旧高松矿田的1783件断裂构造地球化学样品的13种元素进行了多重分形统计以及局部奇异性方法分析.结果表明:多重分形维谱函数α-f(α)曲线呈连续上凸的特征,曲线的不对称反映了元素局部富集程度差异,并据此将13种元素划分为包含Sn、Cu、Pb、Ag、As、Mn在内的主要成矿元素组合以及包含Zn、Sb、Cd、W、Mo、Bi、Hg的次要成矿元素或伴生元素组合.多重分形的特征值τ″(1)以及Dq的变化规律表明:在主要成矿元素中,Sn在断裂空间上局部富集程度最高,其次为Ag,而Cu相对最低,各元素的τ″(1)值与对应的变异系数的大小具有较为显著的相关性:各元素在空间上的奇异性指数α增强了地球化学富集地段的指示信息,可以作为判别局部富集的重要参数.运用多重分形方法可揭示矿化元素局部富集的奇异性特征以及空间局部富集规律.
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