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The Shaki porphyry copper(gold) deposits are a trpical example of porphyry copper deposits associ-ated with diorite in eastern China. Quartz diorite, which hosts the deposits, has a Rb-Sr isochron age of 127.9±1.6Ma. Geochemically, the rock is rich in alkalis (especially sodium), light rare earth elements (LREE) and large-ionlithophile elements (LILE), and has a relatively low initial strontium isotopic ratio (I_(Sr)=0.7058); thus it is the productof differentiation of crust-mantle mixing source magma. The model of alteration and mineralization zoning is similarto the Hollister (1974) diorite model. The ore fluids have a relatively high salinity and contain significant amounts ofCO_2, Ca~(2+), Na~+ and Cl~-. The homogenization temperatures of fluid inclusions for the main mineralization stage rangefrom 280 to 420℃, the δ~(18)O values of the ore fluids vary from 3.51 to 5.52‰, the δD values are in the range between-82.4 and -59.8‰, the δ~(34)S values of sulphides vary from -0.3 to 2.49‰, and the δ~(13)C values of CO_2 in inclusionsrange between -2.66 and -6.53‰. Isotope data indicate that the hydrothermal ore fluids and ore substances of theShaxi porphyry copper (gold) deposits were mainly derived from magmatic systems.
The Shaki porphyry copper (gold) deposits are a trpical example of porphyry copper deposits associ-ated with diorite in eastern China. Quartz diorite, which hosts the deposits, has a Rb-Sr isochron age of 127.9 ± 1.6Ma. Geochemically, the rock is rich in alkalis (especially sodium), light rare earth elements (LREE) and large-ionlithophile elements (LILE), and has a relatively low initial strontium isotopic ratio (I_ (Sr) = 0.7058); thus it is the product of differentiation of crust-mantle mixing source magma. The model of alteration and mineralization zoning is similarto the Hollister (1974) diorite model. The ore fluids have a relatively high salinity and contain significant amounts of CO_2, Ca 2+, Na ~ + and Cl ~ -. The homogenization temperatures of fluid inclusions for the main mineralization stage range from 280 to 420 ° C, the δ ~ (18) O values of the ore bodies vary from 3.51 to 5.52 ‰, the δD values are in the range between -82.4 and -59.8 ‰, the δ ~ (34) S values of sulphides vary from -0. 3 to 2.49 ‰, and the δ ~ (13) C values of CO_2 in inclusionsrange between -2.66 and -6.53 ‰. Isotope data indicate that the hydrothermal ore fluids and ore substances of the Shaxi porphyry copper (gold) deposits were mainly derived from magmatic systems.