Geological Characteristics And Genesis Analysis Of Dongshenmiao Lead-Zinc Ore Deposit In The Inner Mongolia

On the basis of generally analyzing the previous data and references, in combination with geological survey and sample analysis, this paper has dealt with the strata, structures, ore bodies and mineral deposits of the southern parts of Sanguikou at Dongshengmiao in the Inner Mongolia, the new viewpoints on the genesis of ore deposits in this area have been worked out and the metallogenic models established.1,Through measuring the Geological section in this area, which shows that the strata comes mainly from Mesoproterozoic Langshan group, which can be divided into three formations from bottom to upper: the first formation, the second formation and the third formation. The second formation is the host stratus, where the 9th ore body which is the largest one in this deposit occurs.2,By means of researching the size, shape and distribution of the main structures in this region, the author has identified the spatial patterns and changes of the main ore-controlling structures, and found that the ore bodies are strictly controlled by the Nayun mountain syncline and the Northern parts of Nayun mountain anticline, however, which can not affect the continuity of the ore bodies.3,The multiple ore reserves have been blocked out at the southern parts of Sanguikou, and the author has identified that the shapes of the main ore bodies which host in the Langshan group are mainly layered, stratiform-like and Partial lenticular.4,According to the analyses of rare earth elements(REE), together with the ratios ofΣLREE andΣHREE, which shows that the ore-forming Materials come from land-based sources, and Ce losses means that the pre-existing rocks in this region formed in marine reducing environment.5,The ratios of Co/Ni of Pyrite in this deposits are more than one or less than one, which shows that the Dongshengmiao deposits is characterized by SEDEX.6,According to the geological features of mineralization and varieties chemical tests in this area, the results show that Dongshengmiao deposit is an SEDEX reformed by the late hydrothermal fluid, SEDEX mineralization is the main period, the late hydrothermal fluid result in the further enrichment of ore-forming elements in the ore bodies, and then the metallogenic models have been established.