利用多金属矿床中不同阶段形成的方解石Fe,Mn,Sr的质量分数及C,O,Sr的同位素特征探讨成矿过程中的流体性质,并尝试对成矿机制及其过程进行定量模拟.分析表明:①成矿期形成的方解石中Fe,Mn的质量分数明显增高,大部分Mn的质量分数高于1％,是岩浆期后热液作用的反映,利用阴极发光强度可区分不同期次沉淀的方解石；②d(13C)和δ(18O)的联合变化趋势可定性判别方解石的沉淀机制,结合流体中碳氧同位素背景值可对方解石及与之伴生的多金属矿物沉淀过程进行定量模拟；③不同成矿区具有特定的87Sr/86 Sr值区间,该值可作为区分不同端元流体的有利依据.Sr-87Sr/86 Sr体系可用于蚀变-成矿体系中的流体/岩石值以及不同来源流体中Sr贡献度的定量计算；④成矿过程均伴随有放射性成因锶加入,古老铝硅酸盐是成矿物质的主要母源.%This paper tries to discuss the mineralizing fluid property during mineralization and simulate metallogenetic mechanism and process quantitatively on basis of characteristics of Fe, Mn, Sr content and C, O, Sr isotope value of calcite from polymetallic deposit. The analysis indicate that 1) the intensity of cathodoluminescence could be used to distinguish calcite of different stages and the content of Fe and Mn increase obviously in calcite during the metallizing phase and the majority content of Mn was more than one percent that is the reflection of postmagmatic hydrothermal activity; 2) The precipitation mechanism of calcite could been distinguished qualitatively based on the conjuncture variational tendency of δ13C and δ18O value and combined with the δ13 C and δ18 O value in fluid precipitation process of calcite and polymetallic minerals associaed with the calcite could been simulated quantitatively; 3) each metallogenic provinces have specific 87Sr/86Sr value range which is the basis for distinguishing the end fluid. The Sr vs 87Sr/86Sr system could been used to calculate the fluid-rock ratio value and contribution of Sr content from different fluid in alteration-mineralization system quantitatively. 4)The radioactive Sr is involved with the mineralization and ore materials are derived from the paleo-aluminosilicate rocks.
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