浙江芙蓉山破火山口构造特征及火山—侵入杂岩的成岩物质来源
THE FEATURES OF THE MOUNT FURONG CALDERA STRUCTURE IN ZHEJIANG-MATERIAL SOURCE OF THE INTRUSIVE COMPLEX
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摘要: 芙蓉山破火山口构造以其独特的地貌形态,完美的环状断裂和环状岩墙,环形展布的航磁异常和地球化学异常,显示出一个地质—地球物理、地球化学相结合,岩相—构造配置较完整的典型破火山口模式。依壳、幔二元混合模型方法计算,火山岩和侵入岩源区物质组成为UC 71.16 DM 28.84和UC 70.84 DM 29.16。根据元素分配理论定量模拟岩石的成岩过程,芙蓉山地区的火山—侵入杂岩的初始岩浆,是源区约31%的物质熔融而成。Abstract: With its distinctive geomorphological features, perfect ring faults and dikes and aeromagnetic and geochemical anomalies that spread in a ring form, the Mount Furong caldera structure displays a typical caldera model characterized by the integration of geological-geophysical-geochemical features and a relatively complete composition of lithofacies-structure. Calculation by use of the binary (crust-mantle) mixed model, the material compositions of the volcanic and intrusive rock provenances are UC 71.16 DM28.84 and UC 70.84 DM29.16. According to the process of rock formation simulated quantitatively in the light of the element partition theory, the primitive magma of the volcanic-intrusive complex in the Mount Furong area was derived by about 31% of partial melting of source rocks.