基于多重分形理论的地球化学场分解与元素组合研究--以铜山岭-祥霖铺地区为例

摘要

Located in southwest Hunan Province and at the center of Nanling metallogenic belt, the Tongshanling⁃Xianglinpu area, in which several W⁃Sn and Cu⁃polymetallic deposits have been found, has great potential for the prospecting. In this paper, the multifrac⁃tal theory, i.e., the model of singularity, was applied to the decomposition of geochemical fields, on the basis of the data of 1∶50 000 geochemical survey obtained in the study area. The representative elements Sn and Ag were analyzed in detail, with good results a⁃chieved:the singularity reduced the influence of the high background value of rock mass and the variety background levels and intensi⁃fied the anomalies in low⁃value background zone;the fractal density reduced the influence of the data noise effectively, and the anoma⁃lies became more clear. This paper discussed the characteristics of element association preliminarily, and pointed out that it�s better to make a comprehensive analysis in combination with the respective advantages of original data and singularity.%铜山岭—祥霖铺地区位于湖南省西南部，南岭成矿带的中部，已发现多处钨锡、铜多金属矿床，具有较大的成矿潜力。笔者应用多重分形理论———奇异性指数模型对研究区1∶5万地球化学测量数据进行地球化学场分解，选取具有代表性的Sn、Ag进行详细分析，取得了较好的应用效果：奇异性指数有效降低了岩体高背景、系统背景差异的影响，并且强化了低背景区的弱异常；分形密度有效压制了数据噪声的影响，使异常更为清晰可靠。应用奇异性指数对元素组合特征进行了初步讨论，指出在元素组合特征分析中可结合元素原始值与奇异性指数各自的优势进行综合分析。