Crystal Tuff Zircon LA-ICP-MS U-Pb Ages from the Lower Jiangbasitao Formation in the East Daheishan Area, Xinjiang and Their Geological Implications
详细信息
- 责任者：Fan Tingting (State Key Laboratory of Continental Dynamics ; Department of Geology ; Northwest University ; Xi’an 710069 ; China) ; Zhou Xiaohu
- 刊名：Acta Sedimentologica Sinica
- 出版年：2011
- 卷期：29(2)
- 关键词：凝灰岩 ; tuff ; 铀—铅计时 ; U-Pb dating ; 新疆 ; Xinjiang
- 页码：p.312-320
- 图表：6 illus., 1 table, 26 refs.
- 分类号：0803
- issnNo：ISSN1000-0550
- isbnNo：CN62-1038/P
摘要
The Daheishan area is located in the south of the Santanghu Basin, north to the Balikun-Kaerlikeshan, and is adjacent to the Tuha Basin, which is located in the Paleozoic Orogenic Belt of eastern edge of Junggar Basin. Two crystal tuff horizons (No. DHS04N and DHS07N) are sampled from the Jiangbasitao Formation of Lower Carboniferous and are dated using zircon LA-ICP-MS method. The analysis shows that the zircons are of typical magmatic origin with oscillatory zoning. Samples of DHS04N have a uranium content of 63～642 μg/g, thorium of 19～1037μg/g, and a Th/U value range between 0.29 and 1.89. With respect to the origin of the zircons, the authors suggest that they were derived from areas between the two ophiolite belts, because the study area was restricted by the paleooceanic basin (Zhaheba Aermantai ophiolite ophiolitic melange belt) and back-arc basin (Kelamaili-Takezhale ophiolite ophiolitic melange belt).