REE and Nd-Sr Isotopic Compositions of the Iron-Rich Siliceous Rock in Bikou Terrane: Implication to Ancient Sedimentary Environment
详细信息
- 责任者：Song Shigang (Faculty of Earth Resources ; China University of Geosciences ; Wuhan 430074 ; China) ; Ding Zhenju
- 刊名：Journal of Mineralogy and Petrology
- 出版年：2008
- 卷期：28(3)
- 关键词：变沉积岩 ; metasedimentary rocks ; 秦岭 ; Qinling Mountains
- 页码：p.57-63
- 图表：4 illus., 2 tables, 25 refs.
- 分类号：0802
- issnNo：ISSN1001-6872
- isbnNo：CN51-1143/TD
摘要
The REE distribution patterns of iron-rich siliceous rock samples in Bikou terrane showed commonly with Eu positive anomalies,δEu=1.02～8.79, varied Ce negative anomalies,δCe=0.44～1.26, and relative depleted LREE and enriched HREE, (La/Yb)N=0.071～1.285. These parameters are similar to those of hydrothermal vent fluid on modern seafloor and indicate that the siliceous rocks were hydrothermal exhalative sedimentation generated by the convectional mixing of seawater and hydrothermal fluid on ancient seafloor. Y/Ho ratio in siliceous rock samples ranges from 22 to 47, correlating with Ce/Ce* ratios obviously, reflecting that both ratios were controlled by two end members of hydrothermal fluid and seawater.