| Abstract: | The Jinping mountain region on the western margin of the Kang\|Dian axis is situated in the area bordered by the eastern margin of the Qinghai—Xizang Plateau on the west and the western margin of the Yangtze plate on the east, and consists of three\|layer structures: basement (Kang\|Dian axis), detachment zone (sliding surface of lateral extension and thrusting) and the overburden of the Jinping mountain nappe. The intense intracratonic deformation and metamorphism within the Kang\|Dian axis resulted in the activation, migration and enrichment of mineral elements and finally the formation of ore deposits in the Jinping mountain region. As for the Kang\|Dian axis as the crystalline and folded basement, the lower background values ((0 4～0 8)×10 -9 ) of the element Au don't represent the initial contents, which have mostly been activated and moved away.. In the Lizhuang\|Lawo\|Bazhe zone as the detachment structural zone, the high er background values ((6～10)×10 -9 ) of the element Au don't represent the initial contents as well, which have received more gold from the multistage ductile shear zones in the detachment zone. As a result of the lower degrees of deformation and metamorphism within the overburden of the Jinping mountain nappe, the lower temperatures and pressures are insufficient to activate and migrate the element Au; the Au contents available represent the initial Au contents ranging between 1 6 and 2×10 -9 , which are equal to the crustal clarke values from Li Tong and Dai Wentian. The activation and migration of the element Au are believed to be governed by the temperatures and transported media especially variable valent elements and their compounds (principally H 2O, Cl, CO 2 , S and Fe). The associated sediments are also correlated with the transported media especially the valence numbers of the above\|mentioned multivalent elements. The element Au often behaves as a liquid phase element and a multivalence\|phile element in the course of deformation and metamorphism, in which the active components such as H 2O, S, OH - and SiO 2 tend to be moved away to form fluids, while the enrichment process of the inactive ones such as Zr, Ti and P and trace elements is referred to as the defluidization of the rocks due to the variations in mineral phases and formation of different deformational fields (P—Q fields) during the deformation and metamorphism. The widespread defluidization within the Kang\|Dian axis as the basement may allow the element Au with the lower background values to be moved away within the extent of the granulite facies and high amphibolite facies or moderately deep and deep structural facies. The detachment zone of lateral extension and thrusting is manifested as the migration surface of the ore\|forming fluids and the transformation surface of the physicochemical fields of mineralization. In general, the metamorphic facies include greenschist facies and low amphibolite facies or shallow to moderately deep structural facies. It can be seen that both the dynamic and thermodynamic factors are favourable for the emplacement and mineralization of ore\|bearing solution. The further enrichment of mineralized material may permit the first\|order source beds to develop. The temperatures within the overburden are not high enough to be favourable for the activation and migration of Au. (The best conditions for gold migration is in the greenschist facies. The defluidization of the rocks in the higher\|grade metamorphic facies may cause Au to be activated and moved away easily, whereas the dehydration of the rocks in the lower\|grade metamorphic facies may not do so.) It appears that almost all of the rocks are capable of contributing sufficient mineralized material for the formation of gold deposits. The defluidization of the rocks is a key process in the course of deformation and metamorphism. The amphibolite facies, granulite facies and even higher\|grade metamorphic facies are generally favourable for the activation and migration of gold due to the more complete and thorough de |
