Time Constraints, Tectonic Setting of Dalabute Ophiolitic Complex and Its Significance for Late Paleozoic Tectonic Evolution in space prefix = st1 ns = "urn:schemas-microsoft-com:office:smarttags" />
详细信息
- 责任者：Chen Shi (Key Laboratory of Orogenic Belts and Crustal Evolution ; Ministry of Education ; School of Earth and Space Sciences ; Peking University ; Beijing 100871 ; China) ; Guo Zhaojie
- 刊名：Acta Petrologica Sinica
- 出版年：2010
- 卷期：26(8)
- 关键词：构造演化 ; structural evolution ; 蛇绿混杂堆积 ; ophiolite complexes ; 准噶尔盆地 ; Junggar Basin
- 页码：p.2336-2344
- 图表：4 illus., 1 table, 47 refs.
- 分类号：0300
- issnNo：ISSN1000-0569
- isbnNo：CN11-1922/P
摘要
Yegezikala granite situated near Saertuohai, one typical stitching pluton, intruded into Dalabute ophiolitic complex. The SHRIMP zircon U-Pb dating results of Yegezikala granite yield an age of 308 ± 3 Ma (MSWD = 0.83), which indicates the emplacement of Dalabute ophiolite might be before 308 Ma. Due to the formation age of gabbros (Sm-Nd isochron age 395 Ma, LA-ICP-MS zircon U-Pb age 391 Ma) in Dalabute ophiolite, the formation age of Dalabute ophiolite is well constrained. Both sides of Dalabute ophiolite are Lower Carboniferous volcanic-sedimentary strata with continuous strata sequences and comparatively distinct rock associations, so Dalabute ophiolite is not a suture zone. Integrating the previously proposed tectonic models such as slab window and accretionary wedge, the authors infer that Late Paleozoic tectonic evolution in West Junggar is dominated by the passive basin filling in the residual paleo-oceanic basin and the Paleozoic accretion accompanied by subduction of paleo-oceanic crust in West Junggar ceased before Late Carboniferous determined by the stitching granites and diorite dykes.