Early-middle Permian Tectonic-lithofacies Palaeogeographic Characteristics in Qaidam Basin and Its Adjacent Areas
详细信息
- 责任者：Chen Shoujian (Xi＇an Institute of Geology and Mineral Resources ; Xi＇an 710054 ; China) ; Chen Fenning
- 刊名：Journal of Earth Sciences and Environment
- 出版年：2012
- 卷期：34(2)
- 关键词：沉积岩相 ; lithofacies ; 古地理 ; paleogeography ; 二叠纪 ; Permian ; 柴达木盆地 ; Qaidam Basin
- 页码：p.1-14
- 图表：illus., 1 table, 18 refs.
- 分类号：0830
- issnNo：ISSN1672-6561
- isbnNo：CN61-1423/P
摘要
Through the field observation, the analysis of test data, the comprehensive regional geological survey and the previous research result, the forming mechanism and tectonic-lithofacies paleogeography during the Early-middle Permian in Qaidam Basin and its adjacent areas were discussed. The results showed that the Early-middle Permian in the central and northern parts of Qaidam Basin and its adjacent areas was intracontinental basin-and-range and rift valley system, and mainly located on extensional tectonic setting, and the tectonic paleogeography was graben and horst alternately the Early-middle Permian in the southern part was the period with most violent expansion cosmically in Bayankala ocean basin, and ocean-island and seamount were all over the ocean basin; the strong Hualixi tectonic movement in the late of Early-middle Permian caused that the relative movement was intensified between the ancient plates, the ocean lithosphere plate of Bayankala ocean basin dived to the north, so that East Kunlun epicontinental magmatic arc and the accretion zone in south were formed, magmation in the arc was strong,Zongwulong Mountain-West Qinling Mountain terrigenous rift basin further developed, and the complicated teetonic-lithofacies paleogeography was formed subsequently. The Early-middle Permian was the turning point from violent expansion to violent convergence for geodynamics mechanism in Qaidam Basin and its adjacent areas; strengthening the study on the tectonic- ithofaeies paleogeography was significant for building the stratum sequence, discussing the geological evolution history and mineral deposit prospecting.