| The southeast Hunan polymetallic mineralized concentration area is one important part of the Nanling polymetallic mineralized belt. The abundant polymetallic deposits were related closely with Yanshanian magmatic activities; large and Super scale polymetallic ore deposit, as the Shizhuyuan, Qitianling, Xianghualing, Huangshaping, Baoshan, Shuikoushan and Tongshanling deposit etc.are found in granitic bodies and country rocks. On the basis of researching the features of geological structure and facieology, isotope chronology, mineral chemistry, petrochemistry, microelement analysis and test, isotopic chemistry tracing of the main Yanshanian metallogenetic granitoids, the author studied the classification of rock assemblage and background of geochemistry of different metallogenetic granites, the ore body time-space controls of geological structure as well as the source formation mechanism of granitic magma, the process of regional crust-mantle interaction, mineralization and ore finding orientation etc. and obtained some recognitions as follows: 1. Confirmed rock age by Zircon SHRIMP and other ages, the author founded the chronological framework of metallogenetic granites, The period of granide diagenesis is divided into 4 episodes and the main metallogenetic times is the early Yanshanian, with metallogenetic fastigium of Middle Jurassic(155±10 Ma). 2. Calibrated the lithodemic units of 17 typical metallogenetic granitic bodies. According to proportion of mantle material and the relationship between granitoids and mineralization systems, the author brings forward that the type of metallogenetic granitic assemblages and mineralization systems, which is classified into 4 granitic rock assemblage hierarchies and series of mineralization, namely MS-type, SM-type, C-typical aluminous A-type and strong prealuminous S-type granite. 3. The author studied the components of main rock-froming minerals, major and trace elements geochemistry and mineralization of different metallogenetic granitic assemblages types. 4. Found the mark of crust-mantle mixing effect—mafic microgranular enclaves, revealed the characteristics of the crust-mantle mixed magma based on the geological structure, character of petrography, lithogeochemical tracer of the different types of petrosal assemblages of memtallogenetic granitic bodies, remodeled the former understands about the genesis of Yanshanian granites, and provided new foundation for the research of the relationship crust-mantle mixed granitoids and mineralization. 5. It is revealed that the source of different types of metallogenetic granitic assemblages is mainly crustal materials, with mantle material adding. According to simulative calculation, the proportion of alkali basaltic magma in MS-type, SM-type and C-typical aluminous A-type granites is apart ﹥20%,﹤15% and ﹤10%. 6. based on the analysis of crust-mantle interaction, the author discovered that the earlier units of same granite sequence have lower degree magma mixing, with more mafic microgranular enclaves; and the later units have higher degree magma mixing, with less mafic microgranular enclaves. The author considered that there existed high degree crystal detaching after magma mixing, and the early magma mixing and later crystal detaching were probably the primary forming mechanism of metallogenetic bodies. 7. searched the relationship between granitic forming and regional tectonic evolution, and considered that the genesis of early Yanshanian granitic rocks was related closely to the bottom intrution of basalt magma. In the early stage of early Yanshanian, intercontinental collision mountain-making caused obvious structural difference between two sides of Chaling-Chenzhou Fault; and in the late stage of early Yanshanian with post-orogenic tectonic environment; since the crust and mantle is thicker in east upwarping Region, the lithosphere was delamilated, which caused basalt underplating and brought about melting of a huge amount of crystallized schist in made the middle crust, and large-scale magma room formed. At the same time, relatively less basaltic magma from mantle up-intrusived to middle crustal magma room along the abyssal faults, and fromed the mixed magma. 8. Summarized the metallogenic specialization of each petrosal assemblage type , created marker for ore finding and analyzed ore finding potential and favorable trend.
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