Geochemical Characteristics and Environmental Implications of Middle Jurassic Shaximiao Formation, Western Margin of Sichuan Basin
详细信息
- 责任者：Qian Lijun (Institute of Sedimentary Geology ; Chengdu University of Technology ; Chengdu 610059 ; China) ; Chen Hongde
- 刊名：Acta Sedimentologica Sinica
- 出版年：2012
- 卷期：30(6)
- 关键词：沉积环境 ; sedimentary environment ; 岩石地球化学 ; lithogeochemistry ; 四川盆地 ; Sichuan Basin
- 页码：p.1061-1071
- 图表：5 illus., 4 tables, 57 refs.
- 分类号：0803,0600
- issnNo：ISSN1000-0550
- isbnNo：CN62-1038/P
摘要
Choosing the trace elements and REE measured value of 17 samples of middle Jurassic Shaximiao Formation of western margin of Sichuan basin.Results indicate that,in the study area,both the Sr/Ba ratios of the upper and lower Shaximiao Formation are less than 1,which illustrate that there was a fresh water environment during deposition of Shaximiao Formation.The characteristic values and ratios of trace elements and REE such as V, U, Mo, V/Cr, Ni/Co, U/Th, (Cu+Mo)/Zn, V/(V+Ni), δCe, δEu, ∑REE, La/Yb, suggest that the bottom water of the lake was moderate oxidation environment during the whole time Shaximiao Formation deposition. According to the Sr/Cu ratios and the research findings before,the authors suggest that there paleaoclimate was warm and arid with cool interphases during the whole time of lower Shaximiao Formation,and after then it turned to worm and aridity again during the upper Shaximiao period,which is as the lower Shaximiao Formation,and the aridity strengthened gradually.