line-level: 2" class=MsoNormal>The Major and REE Geochemistry of the Silikou Chert in Northern
详细信息
- 责任者：Chang Huajin (School of Life and Geography Sciences ; Qinghai Normal University ; Xining 810008 ; China) ; Chu Xuelei
- 刊名：Acta Sedimentologica Sinica
- 出版年：2010
- 卷期：28(6)
- 关键词：硅质岩 ; silicolite ; 广西 ; Guangxi
- 页码：p.1098-1107
- 图表：5 illus., 56 refs.
- 分类号：0603
- issnNo：ISSN1000-0550
- isbnNo：CN62-1038/P
摘要
The Silikou chert in Northern Guangxi Province was deposited in a terminal Ediacaran to Early Cambrian (about 550 ～540 Ma) deep ocean basin. It has high SiO2 concentration (average 93.8%). Al2O3 content ranges from 0.17% to 4.92% and increases from the lower to the upper section which is more than 2%. Al/(Al + Fe + Mn) and Fe/Ti ratios for most of the chert are more than 0.42 and less than 16.3, respectively. The major and rare earth elements characteristics of the Silikou chert suggest hydrothermal fluids and terrigenous detrital input were not main sources of the silica. In fact, huge amounts of dissolved silica derived from chemical weathering due to high CO2 concentration in the atmosphere and degradation of organic matter were the basic cause for the basinal chert in South China.