Abstract:An examination of the geochemical fields of two porphyry copper deposits reveals that the country rocks surrounding the ore deposits are enriched in copper and in contrast, the weak-alteration zones have wide copper-depletion fields. The amount of copper transfered from these fields is estimated to have been so large that a small portion of it would be enough to form these ore deposits. The time and spatial relationships, alteration assemblages, Sr, S, O, H isotope determinations and data of liquid inclusions and brine or porphyry deposits all demonstrate that, in addition to large amounts of metals, waters and mineralizers might also have been directly or indirectly derived from the country rocks. In order to illustrate the alteration and mineralization processes, three major stages of copper mineralization in Duobaoshan are discussed. They are the widespread early propylitization stage, the biotitization stage of late magmatic process and the sericitization stage of post magmatic period. Magmatic water and meteoric water seem to have been both involved in the alteration and mineralization of porphyry deposits. However, the oxygen and hydrogen isotopic data suggest that magmatic water was actually' a kind of meteoric water which had entered the magmatic chamber and isotopically reached an equilibrium with magma. During the evolution of porphyry copper system, meteoric water must have camed large amounts of mineralizers and ore metals when it entered the magmatic chamber. The mineralization mechanism of porphyry deposits, therefore, was probably one of "absorption followed by excretion under the action of magma"。
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杜琦.1984.以我国一些斑岩铜矿为例试论斑岩矿床成矿与地层（围岩）的关系[J].矿床地质,3(2):21~27.1984.The Relationship Between Mineralization Processes Of Porphyry Ore Deposits And Country Rocks As Examplified By Two Porphyry Copper Deposits In China[J].Mineral Deposits3(2):21~27
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