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A number of Fe-Ti oxide and Fe-Cu sulfide exsolution phases are found in amphibole cumulate xenoliths from Mesozoic granodioritic plutons at Jiguanshi and Jin- kouling in Tongling, Anhui Province. Most of amphiboles in the xenoliths have been identified as pargasite, and deter-mined as a crystallization phase in the lower crust. The oxide exsolutions commonly acicular, are distributed parallel to [100] of amphibole with a typical Schiller texture. They con-tain 0.29%—51.07% of TiO2, and correspond to magnetite, titaniferous magnetite, titanomagnetite or ilmenite. All ex-solved sulfide grains, being rounded to extended rounded in shape, are regularly arranged in sub-paralleled or closely beaded groups, except for a few of grains that are scattered or isolated. The exsolved sulfide phases comprise mostly pyrrhotite, secondarily cubanite and chalcopyrite, and rarely pyrite. A few grains of magnetite can coexist with pyrrhotite in most samples. The sulfide phases are poor in nickel (usu-ally Ni < 0.5%, Ni/Fe < 0.003), while relative enrichments in copper (up to 2.93%) typify the pyrrhotite. Additionally, both oxides and sulfides may be exsolved in the same area of amphibole. Occurrence of Fe-Ti oxide and Fe-Cu sulfide exsolution phases in the xenoliths leads to inference that ore-forming materials such as S, Fe, Cu, etc. have been pri-marily dissolved in Mesozoic magma within the lower crust beneath the Tongling area.
A number of Fe-Ti oxide and Fe-Cu sulfide exsolution phases are found in amphibole cumulate xenoliths from Mesozoic granodioritic plutons at Jiguanshi and Jin-kouling in Tongling, Anhui Province. Most of amphiboles in the xenoliths have been identified as pargasite, and deter They also have a parallel tribute to a typical Schiller texture. They con-tain 0.29% -51.07% of TiO2, and correspond to magnetite, titaniferous magnetite, titanomagnetite or ilmenite. All ex-solved sulfide grains, being rounded to extended rounded in shape, are regularly arranged in sub-paralleled or closely beaded groups, except for a few of grains that are scattered or isolated. mostly pyrrhotite, secondarily cubanite and chalcopyrite, and rarely pyrite. A few grains of magnetite can coexist with pyrrhotite in most samples. The sulfide phases are poor in nickel (usu- ally Ni <0.5%, Ni / Fe <0.003), while relative enrichments in copper (up to 2.93%) typify the pyrrhotite. and Fe-Cu sulfide exsolution phases in the xenoliths leads to inference that ore-forming materials such as S, Fe, Cu, etc. have been pri-marily dissolved in Mesozoic magma within the lower crust beneath the Tongling area.