| 摘要: |
| 为了探讨龟山岛附近热液自然硫烟囱体的物质来源, 通过测定烟囱体内铅同位素的组成特征, 分析了该地区热液活动的铅元素物源。研究结果表明, 龟山岛附近热液自然硫烟囱体中的铅同位素组成具有很小的变化范围和较均一的铅同位素组成特征, 但是与其它深海热液沉积物的铅源不同, 与北半球铅同位素的参考线(NHRL)相距甚远。虽然自然硫烟囱体出现在海水环境, 但是海水对其不存在铅的贡献, 烟囱体内的元素铅主要是陆壳来源。根据以上结果可以进一步推断, 龟山岛热液活动区的下伏地层中, 存在一定分布范围的陆壳, 这对于研究该地区复杂的地质构造特征具有一定意义。
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| 关键词: 铅同位素组成, 自然硫烟囱体, 海底热液活动, 龟山岛 |
| DOI：10.11693/hyhz200904002002 |
| 分类号: |
| 基金项目:中国科学院知识创新工程重要方向项目, KZCX2-YW-211 号, KZCX3-SW-223 号；国家自然科学基金项目, 40830849 号和国家大洋重大专项课题, DYXM-115-02-1-03 号 |
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| LEAD ISOTOPIC COMPOSITIONS OF NATIVE SULFUR CHIMNEYS FROM NEARBY KUEISHANTAO ISLAND IN NORTHEAST OF TAIWAN AND ITS GEOLOGICAL IMPLICATIONS |
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LIU Chang-Hua1, WANG Xiao-Mei1, ZENG Zhi-Gang1, JIANG Xue-Jun2, YIN Xue-Bo1, CHEN Chen-tung A3
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1.Institute of Oceanology, The Chinese Academy of Sciences;2.Qingdao Institute of Marine Geology;3.Institute of Marine Geology and Chemistry, National Sun Yat-Sen University
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| Abstract: |
| For determining the origin of the hydrothermal native sulfur chimney nearby Kueishantao Island, off the northeast Taiwan, geochemistry of lead isotope of native sulfur in the chimneys was studied. The result indicates that the lead isotopic composition is very homogeneous, indicative of a small field of the origin. However, the source of lead is different from those in deeper hydrothermal deposits. Moreover, the lead isotopic scope does not match with the Northern Hemisphere lead isotopic reference line (NHRL). Although the native sulfur chimney was from seawater, the seawater did not contribute the lead isotopics to the chimney-bearing lead but the continental crust did. Therefore, the continental crust beneath the island must have played an important role in material transfer and exchange during the formation of the chimney in the past geological history, which bears implication for understanding the regional complex geological structure and tectonic evolution.
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| Key words: Lead isotopic composition, Native sulfur chimney, Seafloor hydrothermal activity, Kueishantao Island |
