| The paper describes the isotopic characters of hydrogen, oxygen, sulfur, and fluid inclusion characters in geology, and discusses the metallogeny, metallogenic regularities and prospecting indicators for subvolcanic copper-silver-gold-lead-zinc polymetallic deposits in the Mesozoic terrestrial volcanic region of east China. Author also outlines definition for this kind of subvolcanic deposit. It is believed that the subvolcanic type of deposit is based on the subvolcanic rocks developed in accumulated mineralizing area and the mineralization is associated with the occurrence of certain kind of subvolcanic stocks or dikes, which is controlled by the same structure as the mineralization does. Therefore, mineralization and the subvolcanic rock have same origin and same structure in same period. Both have not only a genetic association but also some space and time association. The genetic types of Mesozoic terrestrial subvolcanic copper-silver poly metallic deposit has been confirmed and classified into two subtypes: (a) subvolcanic copper poly metallic deposit, (b) subvolcanic silver poly metallic deposit. Ore matter source, ore controlling conditions and the relationship between the subvolcanic deposit and porphyry deposit are discussed. Almost all the mineralization of subvolcanic type deposit is associated with intermediate-acidic to acidic rocks. Copper polymetallic deposit has a metallogenic specialization with intermediate-acidic rocks, while silver polymetallic deposit is more closely associated with the acidic rocks. REE of ore-bearing rocks mostly collected to 120 X 10~-6~250X10~-6, and the negative anomalies of δ Eu as well as the right-trending curves of the REE partition related to the silver poly-metal indicate that the original magma is from party re-melting of the earth's crust or contamination of the earth's crust and mantle materials. δ Eu of subvolcanic rocks related...
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