关键词: 兴国—宁都成矿带, 断裂构造, 萤石矿床, 分形结构, 应用前景

Abstract: As one of the important non-metallic strategic mineral resources, the metallogenic regularity, ore prospecting and exploration of fluorite are widely investigated byeconomic geologists. The Xingguo-Ningdu metallogenic belt in southern Jiangxi Province, located at the intersection of the NE-trending Wuyishan metallogenic belt and EW-trending Nanling metallogenic belt, develops a series of fluorite deposits. Previous studies have primarily attributed the deposits to fault control, but the quantitative characterization of the coupling relationship between fractures and the spatial distribution of the fluorite deposits is seldom reported. Based on fractal theory, this paper aims to describe the fractal textural characteristics between fractures and fluorite deposits in Xingguo-Ningdu metallogenic belt to identify key ore-forming and prospecting areas of fluorite. The results show that: 1) The NE-NNE-trending fracture capacity dimension, information dimension and correlation dimension of the study area are 1.609 0, 1.608 9, and 1.594 7, respectively, indicating superior metallogenic geological conditions and a strong relationship between NE-NNE faults and fluorite mineralization in the study area; 2) The capacity dimension, information dimension and correlation dimension of fluorite deposits are 0.937 9, 0.921 5 and 0.926  2, respectively. When there is a statistical center deposit, the fractal dimension of the number fractal distribution of fluorite deposits is 0.784 1, and the fractal dimension of the density fractal distribution is 0.784. When there is no statistical center deposit, the fractal dimension of the number fractal distribution of fluorite deposits is 1.129 6, and the fractal dimension of the density fractal distribution is 1.130; 3) According to the coupling characteristics of the fractal dimension value of fracture and the spatial distribution of fluorite deposits in the study area, as well as the fractal characteristics of the number and density of fluorite deposits, the three-level favorable metallogenic areas are comprehensively delineated, in which the I-level favorable metallogenic area is the area with the best metallogenic condition and the largest metallogenic potential; 4) According to the coupling characteristics of fracture dimension value and spatial distribution of deposits, the number and density fractal characteristics of deposits, the key ore forming and prospecting areas in the fluorite ore concentration area or metallogenic belt controlled by fracture system can be quickly and effectively delineated, which is expected to provide important reference information for the resource exploration of fluorite.

Key words: Xingguo-Ningdu metallogenic belt, fracture structure, fluorite deposit, fractal texture, application prospect