Redetermination of the Tanjianshan Group: Geochronological and Geochemical Evidence of Basalts from the Margin of the Qaidam Basin
详细信息
- 责任者：Gao Xiaofeng (Xi’an Institute of Geology and Mineral Resources ; Xi’an 710054 ; China) ; Xiao Peixi
- 刊名：Acta Geologica Sinica
- 出版年：2011
- 卷期：85(9)
- 关键词：奥陶纪 ; Ordovician ; 志留纪 ; Silurian ; 玄武岩 ; basalts ; 柴达木盆地 ; Qaidam Basin
- 页码：p.1452-1463
- 图表：6 illus., 2 tables, 22 refs.
- 分类号：1200
- 出版序号：1891
- issnNo：ISSN0001-5717
- isbnNo：CN11-1951/P
摘要
The Tanjianshan Group distributed widely on the margin of the Qaidam Basin is characterized by distinct differences in rock assemblages,isotopic chronology and geochemical features of basalts,as well as regional mineralization.It has different rock assemblages and sedimentary formation on the northern and southern margins of the Qaidam Basin. The isotopic geochronology and geochemical comparison of basalt from the Tanjianshan Group on the southern and northern margins of the Qaidam basin show that the basalt on the north formed ca.510 to 460 Ma,representing the Cambrian-Ordovician magmatism,while the basalt from the south formed at ca.450 to 440 Ma and was the product of Middle Ordovician-Early Silurian magmatic eruption.