川西北地区控矿断裂的分形特征及其预测意义

断裂构造是控制川西北地区金矿形成与分布的主导因素。运用分形方法定量计算了该区金矿化异常和控矿断裂体系的计盒维数和信息维数。研究结果表明 ,利用地球化学数据二维空间序列的R/S分形方法可以较为精确有效地厘定金矿化的空间结构特征 ,分数维D值的大小能表征控矿断裂体系的复杂性。金矿化带整体上受NW向断裂控制 ,但金矿体则产出于NW向断裂与NE向断裂的复合部位。根据对三个矿化区断裂体系分维特征与金矿发育特征关系的分析 ,发现断裂体系的分维高值区与金矿分布密集区对应。阿坝地块西南缘的找矿前景不如东北缘

FRACTAL FEATURES AND FORECASTING SIGNIFICANCE OF ORE-CONTROLLED FRATURE IN NORTHWEST SICHUAN PROVINCE

The faulted structure is a dominant factor to control the formation and distribution of the gold mineralization in the northwest Sichuan Province. Using the fractal geometric method quantitatiuely calculated the box-counting dimension and information dimension of the gold mineralization anomaly and ore-controlled fault system in this region. The research results show that the R/S analytical method for the two-dimension spatial sequence of the geochemical data can be applied to the relatively accurate and effective delineation of the spatial structure of the gold mineralization, the size of the fractal value can be used to characterized the complexity of ore-controlled faults system. As a whole, the gold metallogenic zone has been controlled by NW fracture system, but the spatial occurrence of the gold orebodies has been controlled by the compound location of the NW and NE faults. From the anlaysis of relationship between fractal dimensions of fault system of the three gold mineralization areas and the distrubution of gold deposits, it is found that the areas with high fracture fractal dimensions are consistent well with the distribution of large gold deposits. The southwest margins is not as good as the northeast margins of the Aba landmass for the gold metallogenic expectation.