Abstract A certain proportion of wall rock alteration is the reflection of ore-forming process. Part of wall rock alteration related intimately to mineralization is early wall rock alteration which took place before the precipitation of ore substances, and its mineral association could chemically accept the precipita tion of ore substances. In fact, such wall rock alteration was the preparation for ore substance precipitation and resulted from the interaction between earlyhydrothermal solutions and favorable wall rock media. It therefore embodies integratedly geochemical environments favorable for ore substance precipita tion. The mineral association of the late altered wall rock resulted from redi stribution of rock-forming elements, and hence geochemical anomalies of rock-forming elements undoubtedly reflect geochemical environments favorable for the precipitation of ore substances.Porphyry copper deposits and kuroko type ore deposits have their respe ctive typical geochemical anomaly models of rock-forming elements, whose distribution forms and quantitative variations are spatially closely related to areas of mineralization and ore-hosting positions. The study of inclusion compo sition, the theory that ore substances migrated in the form of complexes, the material exchange between ore fluid and wall rock and the "metasomatic rock pillar"formed at the beginning of the ore-forming process for the pyrite deposit all indicate that rock-forming elements controlled the migration, accu mulation and precipitation of metallogenic components. Geochemical anomalies of rock-forming elements are not only an important subject in geochemical researches but also an useful indicator in geochemical ore prospecting and evaluation and especially in search for blind ore deposits.
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