Generation of Dawsonite Cement of Pyroclastic Rocks in Tongbomiao Formation in Tanan Sag of Tamtsag Basin in Mongolia
详细信息
- 责任者：Dong Linsen (College of Earth Sciences ; Jilin University ; Changchun 130061 ; China) ; Liu Li
- 刊名：Journal of Jilin University
- 出版年：2011
- 卷期：41(2)
- 关键词：火山碎屑岩 ; pyroclastics ; 碳钠铝石 ; dawsonite ; 蒙古 ; Mongolia
- 页码：p.421-431
- 图表：2 illus., 1 plate, 3 tables, 49 refs.
- 分类号：0700
- issnNo：ISSN1671-5888
- isbnNo：CN22-1343/P
摘要
Dawsonite cement is abundant in pyroclastic rocks in Tongbomiao Formation in Tanan sag of Tamtsag Basin in Mongolia. The stable isotope compositions of dawsonite and ankerite are investigated by MAT253 stable isotope mass spectrometer. Dawsonite δ13C values range from -8.15‰ to -2.81‰, and the calculated values of CO2 gas in isotopic equilibrium with dawsonite range from -12.91‰ to -7.55‰, with analogy of Hailaer Basin and BGS basins, which show that CO2 for forming dawsonite almost from mantle-magma, and andesite debris, crystal feldspar and detrital feldspar, vitric debris and volcanic ash supplying Na+ and Al 3+. Ankerite δ13C values range from -6.76‰ to -2.65‰, which are similar with dawsonite, with related geological and geochemical simulation examples, which note that CO2 for forming ankerite also from mantle-magma. Andesite debris,vitric debris, volcanic ash and montmorillonite which contain ferrum supply metal ions for the formation of ankerite.