| Xikuangshan Type Copper Ore Deposit named those Fe-Cu deposits hosted in Yinmin Formation, Kunyang group, which located in Kunyang rift valley and the edge of southwest yangzi platform. The best example is Xikuangshan allotment, Luoxue ore area, Dongchuan, Yunnan. The type deposit spread in south Kunyang rift valley, include Dongchuan, Wuding-Luoci, Yuanjiang, Yimen, Huashengping, Hongmenchang and so on. 90's it was found in shizishan, yimen, indicated that the type deposit is well explorative prospect in Dongchuan-yinmen.By sum up the data of trace elements, isotopic elements, fluid inclusions and minerogenetic age et al., the following new knowledge are acquired:a) The Cu background of stratum and Jinningian alkali basite is abnormal high, which could be liberated from those rocks during alteration. Cu et al. minerogenetic elements, which main came from magmatic rock, some from stratum (Yinmin Formation and Luoxue Formation) and its basement rocks. Discolorative alteration, the mark of Cu mineralization, is the result of alkali fluid metasomated stratum rocks.b) Ore-forming fluid belong to Na+ (K+) Ca2+-SO42- (CD type fluid of middle-high temperature, salinity, and high density. It was consist of magmatic water came from deep source, some seawater and metamorphic water. N2 -rich inclusions were first founded in ore area; it may form by upper mantle or lower crust material during oxidation-devolatilization reactions.c) Copper ore body surrounded iron ore body; Iron ore were interpenetrated by copper ore stringer vein, which indicated that copper form late than iron. Metallogeneti age is 826± 230Ma, similar with the age of alkali basite and age of other copper deposit in Dongchuan ore area, which belong to Jinningian.d) The invasion of Jinningian-chengjiangian alkali basite were unambiguous, the distribution of those rocks form 'Z' in shape, which similar with Luoyin fracture zone and the distribution of copper deposit. It shows that copper deposits were controlled by discordogenic fault and its derived sub-structure, and there are relationship between copper deposit and Jinningian-chengjiangian alkali basite.e) Most of minerogenetic age of copper deposit, which located in Kunyang rift valley, belongs to Jinningian-chengjiangian (between 900-650Ma), similar with the time limit of breaking- up of Rodinia. It indicates there are close relationship between the forming of copper deposit in Kunyang rift valley and the breaking-up of Rodinia.The minerogenetic model of Xikuangshan type copper deposit can be concluded that: In Jinningian-chengjiangian, the activity of Xiaojiang discordogenic fault form dextrorotation sub-structure in Dongchuan ore area. Luoyin fracture zone were formed ('Z' in shape). Alkali basite, which came from upper mantle or lower crust, invaded through those structure, which not only bring Cu et al mineralizing elements, but also the most important is that thermal energy. It cycled the formation water (Yinmin Fonnation and Luoxue Formation), and form alkali-rich, middle-high temperature and salinity fluid mixed with alkali-rich magmatic water. There were high rate of percolation and well voidage in the contact zone between Yinmin purple stratum and Yinmin rubblerocks, which is in favor of the transposition and mineralization of minerogenetic fluids. Cu et al minerogenetic elements were liberated from stratum by the affection of the mixed fluid, overprinted and alternated the original mineralization, and form Xikuangshan type copper deposit.
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