内蒙古阿拉善右旗拜兴图地区土壤 地球化学异常特征及找矿预测.

In order to preferably select the prospecting prediction target area in Baixingtu area of Alxa Right Banner, 1 ∶ 10 000 soil geochemical measurements were carried out on the basis of identifying the geological conditions of mineralization in the area. Elemental variation coefficients, ILR transform and ILR-PCA multivariate statistical analyses were used to analyze the seven elements : Au, Ag, Co, Cu, Pb, Zn and As in the study area. The results show that : (1) ore-forming elements mainly occure at the intersection of the fracture and mineralized alteration zone. Au and Ag show very strong differentiation and enrichment characteristics with the highest mineralization potential, while Pb, Zn, As, Co and Cu show low differentiation and enrichment characteristics, and low mineralization potential. (2) ILR transformation eliminates the closure effect of the original data and makes the elements show standard normal distribution; the first principal component of ILR-PCA can extract the comprehensive information of the elements of the original data to the maximum extent, i. e., the positive end-load of PC1 (Au-Ag-As) is the mineralization indicator, and the intensity and morphology of elemental anomalies are controlled by the fracture and mineralization alteration zone, and the negative end-load (Co-Cu-Pb-Zn) is caused by the enrichment of elements in multi-phase magmatic hydrothermal activity. (3) Engineering verification of the mineralization target area No.Ⅰ has identified several gold (silver) ore (mineralization) bodies, and the gold and silver contents have reached the minimum industrial grade or above, indicating that the Baxingtu area has a large potential for gold and silver prospecting. [ABSTRACT FROM AUTHOR]

为优选阿拉善右旗拜兴图地区找矿预测靶区, 在查明该区成矿地质条件的基础上开展 1 ∶1 万土壤 地球化学测量。 采用元素变异系数、 ILR 变换、 ILR-PCA 多元统计分析法对研究区 Au、 Ag、 Co、 Cu、 Pb、 Zn 和 As 等 7 种元素进行分析, 结果表明: (1) 成矿元素主要赋存于断裂与矿化蚀变带交汇部位, Au、 Ag 呈现 强分异富集特征, 成矿潜力大; Pb、 Zn、 As、 Co、 Cu 呈现低分异富集特征, 成矿潜力较小。 (2) ILR 变换可 消除原始数据的闭合效应, 使元素呈现标准正态分布; ILR-PCA 第一主成分能最大限度提取原始数据的综 合信息, 即 PC1 正端载荷 (Au-Ag-As) 为成矿指示元素, 元素异常强度和形态受断裂与矿化蚀变带控制, 负 端载荷 (Co-Cu-Pb-Zn) 为多期次岩浆热液活动引起。 (3) 对Ⅰ号找矿靶区进行工程验证, 查明靶区数条金 (银) 矿体, 金、 银含量均达到或超过最低工业品位, 表明拜兴图地区具有较大的金、 银找矿潜力。 [ABSTRACT FROM AUTHOR]