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With little mineral exploration, the study area in the northeast of Inner Mongolia is belonging to the middle segment of the Da Hinggan Mountains. This area is one of the few places with having not been geochemical servey in the scale of 1:200000, so it leads to the lack of geochemical data. This 1:50000 soil geochemical survey can not only supply the geochemical data,but also give the basis for prospecting.The soil element abundance characteristics and the soil element differentiation characteristics are first expounded in the article. The concentration factors of Sb, As, Pb ang Ag in soil are greater than 1.5 which shows that these elements lean to downward enrichment; The coefficients of variation of Pb, As, Ag, Mo, Zn,Hg,Au and Sb are greater than 1 which suggests that the distribution of these elements isn’t even and it is a favorable geochemical factor for mineralizing.Using iterative method to determine the background value and anomaly threshold, and it has checked the feasibility of the method by Q-Q probability graphs. We have drawn the soil geochemical anomaly maps of 12 elements, and have analysed anomalous features and summarized that the numbers of outlier of Ag, Au, Zn, Pb and Mo are more than others; most of them are in 3-grade concentration belt, and the anomalous intension of Pb, Ag, Zn, As, Hg and Mo is higher than others; the anomaly of the most of the elements is more dispersive, the diversity of the anomalous scales is more than others, and the centers of the anomalous concentration are more obvious; the distribution of the anomaly is organized.We have analysed the association and combination characteristics of the soil geochemical elements. The correlation analysis indicate that the correlations among Ag, Pb, Zn and W are higher and the correlation coefficients are above 0.2, even the correlation coefficients of Zn and W are reach 0.78. Combining R-cluster analysis and factorial analysis, we can obtain 6 combine types of elements:F1, Ag-Pb-Zn-W; F2, Au-Cu; F3, Mo-Sb; F4, Bi-Hg; F5, Sn; F6, As. Ag-Pb-Zn-W is the main combination for mineralizing in this area and it is easy to gather in neutral-acidic volcanic rock and helpful for producing Ag-Pb-Zn-W magmatic hydrothermal type multi metallic mineral deposit.We have drawn the combined-anomaly map, and analysed the features of the combined-anomaly. According the combined-anomaly characteristics and the geological background characteristics of anomalous area, we can draw out five first anomaly areas and seven second anomaly areas in the metallogenic combination of Ag-Pb-Zn-W and the A1、A2、A5 anomaly areas are strategic prospecting areas.
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