REE Characteristics and Their Significance of Oncolite Carbonates of the Chuanshan Formatiom in Majiaoba, Jiangyou Region
详细信息
- 责任者：Xu Jinlong (Geological Survey of Anhui Province ; Hefei 230001 ; China) ; Hong Tianqiu
- 刊名：Geological Journal of China Universities
- 出版年：2012
- 卷期：18(4)
- 关键词：核形石 ; oncolites ; 稀土元素 ; rare earths ; 四川 ; Sichuan Province
- 页码：p.724-734
- 图表：5 illus., 3 tables, 49 refs.
- 分类号：0803
- issnNo：ISSN1006-7493
- isbnNo：CN32-1440/P
摘要
Oncoids are well preserved in the Chuanshan Formation in Majiaoba,Jiangyou county. ICP-MS is used to determine REE contents of oncolite carbonate rocks of the study area. Some samples have negative Eu anomalies and some have positive ones,which may indicate that REE characteristics were affected by ancient climate cycles(glacial-interglacial cycle) and the periodical sea level changes,and should be further studied. Y/Ho ratios are closed to the lower limit of modern seawater,which implies that the ancient seawater was affected by the ice melt water. The REE were not only derived from the seawater,but also affected by the bioclast and the genesis of oncolite.