Research On Typical Mineral Deposit Of Xi-An-Shan Iron Ore And Deep Forecast To "An-Shan-Type" Iron Ore

With the fast development of economy, we have to face the poor of mineral resources, including iron ore. So the work that we must investigate and research on mineral resources actively, assess the regional potential of mineral resources scientifically, and provide foundation for the deployment of mineral resources, become more and more important."An-Shan-type"iron ore is the banded iron formations(BIFs) of our country's generated before Cambrian period, and it is the most important iron type for our country, the reserves of which occupy the half or more reserves of iron in China. Thus, the assessment and forecast about the potential of iron in our country depend on the research of"An-Shan-type"iron ore.This article is based on regional metallogenic regularity: firstly, it introduces the researched work by domestic and foreign scholars, which will help us to get to know the research history about BIFs. And then, it uses the research methods and processes of typical mineral deposit to research"An-Shan-type"iron ore. I chose Xi-An-Shan iron ore as the typical deposit .Compared with the foreign BIFs, the BIFs of our country's have their own characteristics, for example, it belongs to Algoma-type, small scale and"Gong-Chang-Ling-type"Hydrothermal metamorphism iron is its iron-rich type. The article also pays more attention to the geological features of Xi-An-Shan iron ore, including stratum, geological structure, activity of magma, metamorphism effect and the geological characteristics of deposit, etc. Through the description to"An-Shan-Qun"stratum, we got the conclusion that the original rock of"An-Shan-Qun"stratum was clay and sand mixed with volcanic materials and iron-silicon formations. The ore-forming process began with the deposition of clay and sand, then deposited iron-silicon formations, and ended with the deposition of volcanic materials, which reveals that the surroundings of deposition was neritic facies. Through the description and the research on the structure of mining area, we think the basement of"An-Shan-Qun"stratum had endured tectonic movement repeatedly. The area of Xi-An-Shan had endured extensive Regional metamorphism, which belongs to Greenschist facies. It had also endured Migmatite-effect many a time, causing Metamorphic rock was encircled by Migmatite. The migmatite of An Shan-Ben Xi area's was not formed one time, but many effects, exactly 3-time main effects. The article generalized the geological characteristics of Xi-An-Shan deposit, including: 1.the scale of ore-body is huge. The thickness of monolayer is over 200m, meanwhile, the length of it is over 4500m and the depth is over 100m. 2. The BIFs in Xi-An-Shan mineral deposit belongs to"An-Shan-Qun"stratum, The Mineralization age of which is over 2100-2400my. 3. The BIFs and their upper-lower wall rock is silicon-iron deposition formations containing clay and sand mixed with volcanic materials according to their chemical compositions. 4. The grade of iron ore is average, however, the central part of iron ore layer is higher and the upper is lower. 5. The BIFs contained dolomite and siderite, which was paragenesised with magnetite, and it proves that all these mineral generated under low acid or neutral surroundings. After describing the geological characteristics of Xi-An-Shan deposit, we tried to establish the Mineralization pattern. Because the Mineralization age of An-Shan-type is so remote and the iron ore-body had endured extensive Regional metamorphism or tectonic movement repeatedly, it's so hard for us to establish the mineralization pattern correctly, so we achieved it by means of grasping key link during Mineralization process. Most of the foreign or domestic scholars held the opinion that the BIFs originated from deposition and then Deterioration. They also thought that the forming of BIFs was related to the oceanic volcano movement. There are two different opinions about the way Mineralization material get into the waters, however, we tended to the opinion that the Mineralization material came from the rocks of seabed. In order to explain the forming process of BIFs, we tried to gather some scholar's opinions to illustrate. We tried to discuss the relations between the development of Liaodong- Land parcel and the BIFs later, and finally, explain the forming process of An-Shan-type rich iron ore. After discussing all these mineralization questions, we had formed the Mineralization pattern map of Xi-An-Shan iron ore. We extracted the mineralization factors on the foundation of the work before and then classified the factors in order to form the Mineralization factors map. According to the principle of Analogy prospecting, we got the forecast factors and the forecast factors map, together with the forecast model map. At the end of the article, I tried to do deep forecast on An-Shan-type iron ore in An Shan deposit.The conclusions of the article:1. On the foundation of the research to Xi-An-Shan typical deposit, establish the Mineralization pattern of Xi-An-Shan iron ore.2. Extract the Mineralization factors and the forecast factors of Xi-An-Shan iron ore, and form he Mineralization factors map, the forecast factors map together with the forecast model map. All these works hadn't done before.3. According to the research results of typical deposit, try to do deep forecast on An-Shan-type iron ore in An Shan deposit. Establish the superficial part and depth portion mine-prospecting models. Form related maps and forecast the amount of resources.