奇异性理论在个旧锡铜矿产资源预测中的应用:成矿弱信息提取和复合信息分解

Application of Singularity Theory in Prediction of Tin and Copper Mineral Deposits in Gejiu District,Yunnan,China:Weak Information Extraction and Mixing Information Decomposition

本研究的目的是应用非线性理论和高新信息处理技术获取矿产资源预测综合信息,开展以有色金属和贵金属矿产资源潜力评价和预测靶区圈定,提交个旧及周边地区矿产资源潜力分布图.围绕该研究任务,重点开展了如何应用奇异性理论和方法,对比个旧东西矿区的异同.由于区域构造和岩体分布等空间变化性,导致东西区成矿背景存在较大差异,受出露地表或近地表矿体分布和矿山开采的影响,东西区的成矿异常强度和大小都存在较大差异,东区总体呈高背景而西区为低背景,因而,对东西区的成矿信息对比研究和异常圈定相对困难.采用局部奇异性分析方法从地球化学分形密度的角度圈定了局部异常,在东西区均较好地反映了致矿地球化学异常的分布,同时采用广义自相似分析方法分解了综合地球化学异常和背景.结果表明,东西区地球化学背景差异悬殊,而局部异常具有显著的自相似性.据此在东西区同时圈定的局部异常具有内在的相似性和表现形式上的多样性,以此为依据所圈定的靶区均具有找矿意义.

New non-linear theory and methods of multifractal singularity are applied to map weak anomalies related to deeply buried ores and mineralization halos. The main contents of singularity theory and methodology include three main principles and models： local singularity analysis （for example A-analysis） for enhancing weak anomalies caused by buried ores, generalized self-similarity analysis （for example C-A and S-A models） for anomaly decomposition and for anomaly and background separation, and fractal spectrum analysis （for example mapping posterior probability） for characterizing spatial distribution of singularities and anomalies. This paper uses the local singularity analysis to map the anomalies not only in the eastern area where known mineral deposits are found but also in the western area where few mineral deposits have been found. It also uses the gen eralized self-similarity analysis method S-A model in integration of the principle component analysis in separating element association anomalies in both eastern and western areas. The results show that the eastern and western areas depict significant background difference and the local anomalies obtained using both local singularity model and S-A model show generalized selfsimilarity in eastern and western areas. Several target areas are delineated on the basis of these local anomalies.