Genesis of the Tianzhushan Intermediate-Felsic Rocks from the Dabie Orogen and Its Geological Significance
详细信息
- 责任者：Liu Lei (State Key Laboratory of Mineral Deposits Research ; School of Earth Sciences and Enginering ; Nanjing University ; Nanjing 210093 ; China) ; Xu Xisheng
- 刊名：Geological Journal of China Universities
- 出版年：2011
- 卷期：17(1)
- 关键词：中性岩 ; neutral rocks ; 酸性岩 ; acidic rocks ; 大别山 ; Dabie Mountains
- 页码：p.136-150
- 图表：10 illus., 5 tables, 41 refs.
- 分类号：0801
- 出版序号：20120149
- issnNo：ISSN1006-7493
- isbnNo：CN32-1440/P
摘要
The Tianzhushan intrusive complex is one of the Late Yanshanian intermediate-felsic complexes in the Dabie orogenic belt, which was emplaced in two stages. The amphibole quartz monzonite of the earlier stage has larger SiO2 content variation ranging from 59.83% to 70.12%, with K2O+Na2O from 7.02% to 9.56%. Sr and Nd isotope geochemical characteristics suggest that the intermediate-felsic rocks were derived from the old lower crust which is similar in chemical composition to the metamorphic assemblage in North Dabie Mountains. New LA-ICP-MS zircon U-Pb dating suggests that the crystallization age of the Tianzhushan complex is (127±1)~(131±1) Ma, in agreement with the ages （120~135 Ma） of the large-scale intrusive intermediate-felsic and mafic-ultramafic rocks in the region.