| Aershan area is an important part of Nangebi-Aershan-Duobaoshan polymetallic mineralization belt, it has the capacity of finding large and medium polymetallic deposit. The prospecting doesn't have great breakthrough in many years, since it is Daxinganling forest cover area, the basic geological research of regional metallogenic setting and metallotectonic dynamics is very weak, plus the low-level of geological exploration. This degree paper depends on the national 1:50000 regional mineral geology survey projects, and based on the previous study results, field geological survey and lab experiments, the main achievements of this paper are shown as follows:1) Three mineralization sub-belts of NE-SW direction have been presented for the first time:①Songshan mineralization sub-belt, it mainly has Fe, lead zinic, Mo, and Cu deposit.②Aershan mineralization sub-belt, it mainly has lead zinic and ferro-manganese.③South-Xing'an mineralization sub-belt, it mainly has Mo(Cu) and specularite.2) A batch of important mineralization information and mineralization points in three mineralization sub-belts have been founded for the first time. For example, in the work process of North-Wuliquan and South-Xing'an, a certain scales of veins have been found. In the meantime, these place exist geochemical anomalies of 1:50000 Pb, Zn, Cu, Mo and W. They are favorable target regions for polymetallic deposit, and expected to forming deposit through further work.3) The age of two metallogenic granite rocks in the study area has been obtained for the first time. The age of metallogenic granite of two representative deposits(points) which are Fe and Mn-polymetallic deposit of hydrothermal vein type, Mo(Cu) deposit of hydrothermal vein type, is always a weak link. According to the U-Pb age determination of high-precision, the age of metallogenic granites is early Indosinian period (237.8±2.3Ma) and middle Yanshan period(152.2±2.9Ma), which is basically respond to the Ulanhot-Solon area.4) The tectonic ore-controlling regularity of Aershan mineralization belt has been generalized. Based on the theory of plate tectonics, the researched area is divided into four tectonic elements. The tectonic ore-controlling regularity of three mineralization sub-belts is generalized into three types, including "north-east fault-folded belt ore-controlling", "north-east Bailang fault-folded belt ore-controlling" and "approximate east-west paleo-Asia tectonic ore-controlling".5) the limited strain analysis of Dashan Fe-polymetallic deposit in Songshan mineralization sub-belt has been studied. According to the three-dimensional strain measurement, the direction of principal axis of strain which is considered the most intense tectonic movement (late Jurassic epoch) has been determined. The direction of major principal stressσ1 is 345°∠18°, direction of intermediate principal stressσ2 is 247°∠9°, and direction of minimum principal stressσ3 is 150°∠72°.6) The skarns contact ore-controlling structure types of Dashan Fe-polymetallic deposit in Songshan mineralization sub-belt, and the spatial variation of Fe-polymetallic lode grade have been researched:ore grade of Fe-ore vein in Dashan Fe-polymetallic deposit has the characteristics of "rich upward and poor downward". On the contrary, ore grade of Mo-ore vein has the characteristics of "poor upward and rich upward". And the ore grade of lead zinc-ore vein has the changing regularity of "rich in the center and poor at the sides" in the plane. Derived fissures of Dashan main fault belts are important ore-controlling structures in mine area. The contact tectonic belts of skarn are divided into eight belts, and according to the ore-controlling features, it divided into three types, including cryptoexplosive breccia pipe-contact structure, fracture-contact structure, and xenolith-contact structure.7) The ore-hunting prospect areas has been delineated. According to the regional metallogenic setting of Aershan mineralization belt, metallotectonic dynamics, and combined with geochemical and geophysical data, eight ore-hunting prospect areas and fifteen prospecting target areas have been divided in three mineralization sub-belts. Based on the prospecting potential from large to small, the ranks of ore-hunting prospect areas are divided into A, B and C, respectively. And all of these lay a good foundation for census prospecting in the future.
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