| Eritrea Anseba region is located in the Arabian- Nubian Shield in the south, Nubian shield, the shield by the new continental margin of ancient Yuan Dynasty(BC 870 ~ 670 trillion) and young oceanic magmatic arc rocks body composition, joint action by the Great Rift Valley and the Red Sea rift, the shield after the long and complex geological evolution, with good geological and tectonic setting of mineralization is typical of Eritrea country polymetallic mineralization belt.Due to the impact of war, so that the country’s mining industry to a halt, the study area prior geological work too little, mainly for small scale remote sensing, geophysical exploration and a small number of regional geological survey. Previous studies, we found that the region has mineralization potential. Relying on paper "Eritrea Anseba region Kerkebet gold polymetallic ore exploration" project, in the pre-collection and comprehensive study on the basis of geological data, by soil geochemical survey to identify the contents and spatial distribution of elements in soils of the region, determine the anomaly threshold of the elements in the soil area, the delineation of the single elements and integrated anomaly. Combined with 1: 50,000 geological mapping and early, the objects, remote data delineate prospect area and make the vision of its analysis. Comprehensive study achieved the following main results and understanding:1, the study area is mainly exposed Neoproterozoic strata Hagar group(Harga) group formation and the formation Nakfa(Nakfa), Nakfa group is the main ore-bearing formations in the eastern mining area have the group rock outcropping; Constituency folds and faults is developed, it is beneficial to mineralization, especially in the intersection fracture site; mining outcropping mafic igneous rocks are mainly- acid rock, rock bigger impact on the mineralization; alteration representing constituencies strong, major alteration silicification, sericite-oriented, kaolin, chloritization, epidotization; mineral constituency mainly associated with zinc, copper and gold massive sulphide minerals, hydrothermal gold deposit structure and structural eclipse metamorphic rock type gold deposit;2, with an average content of rock in the study area elements in the background, the soil Mo, Au, Bi, As, Ag, Sb, Cu, Pb, Zn is significantly enriched in elements, W, Ni element is a significant lack of elements; space on, Mo, Sb, W, Au, Bi, As coefficient of variation is greater than 1, for the strong points profiled element; Cu, Pb, Zn, Co variation coefficient greater than 0.7 is less than 1, for the sub-shaped element.3, through the relevant elements of soil analysis and clustering analysis, soil element group should be divided into two categories: one for the Au-Bi-Sn-Ag-Sb-Cu-Pb-Zn, such elements may be massive sulphide elemental composition of mine, and the other for the W-Co-Mo, such elements may be contacted for granite or metamorphic combination of elements ore;4, as determined by the calculation method of the background and anomaly threshold value of each element of the study area, delineated single element anomalies, abnormal size and strength of the elements are larger. According element combinations of features, the delineation of the nine combinations of soil geochemical anomalies, and its abnormal assessment order, the result is Ahs1- Ahs3- Ghs1- Ahs4-Ahs2- Ghs3- Gohs2- Ghs2- Gohs1; final evaluation of the various anomalies classification, carved out of a class A 1 anomaly, an exception class B 1, 3 Class B 2 abnormal,3 Class B3 abnormal, an abnormal Group C 1;5. The soil geochemical anomalies in the study area, combined with geological information related remote sensing, geological, geophysical this region, a comprehensive analysis of the area circled five prospecting areas, the main ore-forming elements in zinc, copper and gold prospect area Multi-metal-based; and the classification and evaluation of prospective areas, five prospecting areas carved out a Ⅰ grade mineralization prospect area, three grade Ⅱ ORE PROSPECT, a Level Ⅲ ORE PROSPECT. |
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