摘要
华南含锡斑岩可分富氟和贫氟两种亚型。它们具有高硅(SiO_2>71％)、过铝质(AINKC>1.0)、富不相容元素(铷、锆、铀、钨、锡)、弱的铈(δCe=0.68-0.82)和强的铕(δEu=0.01-0.38)负异常;同时,还具有低的ε_(Na)值(-6.3-8.4)、高的^(207)Pb/^(204)Pb值(15.588-15.790)、中等至高的(^(87)Sr/^(86)Sr);值(0.7084-0.7287)和较高的δ^(18)O值(9.1‰-10.3‰)。这些特征清楚地表明,这两种亚型含锡斑岩都来源于地壳物质,其区别仅在于它们的源区物质在成分上存在某些差异。因此,华南只存在一种类型,即陆壳改造型合锡斑岩。
Tin-bearing porphyries in South China can be divided into the F-rich and F-poor subtypes. They are high-silica (SiO2> 71%), peraluminous (A/NKC> 1.0) and rich in incompatible elements (Rb, Zr, U, W and Sn) and have weak Ce (δCe = 0.68-0.82) and strong Eu (δEu = 0.01-0.38) negative anomalies. Meantime, they also possess nather low εNd( -6.3--8.4) , qinte high 207Pb/ 204Pb ( 15.588- 15.790) , medium to high(87Sr / 86Sr)i(0.708 4-0.728 7)and higher δ518O (9.1%-103%). These characteristics clearly suggest that the two subtypes of tin-bearing porphyries were all derived from the crustal materials. Their distinction lies only in that there exist some differences in the composition of source materials. Therefore, there is only one type of tin-bearing porphyry in South China, that is, continental crust transformation type.
出处
《地质学报》
EI
CAS
CSCD
北大核心
1995年第4期349-359,共11页
Acta Geologica Sinica
基金
国家自然科学基金(编号 49070092)
关键词
含锡
斑岩
同位素
物质来源
地球化学
tin-bearing porphyry, isotope, material source, South China
