Role of mantle-derived magma in genesis of early Yanshanian granites in the Nanling Range, South Chi

来源 :Science in China(Series D:Earth Sciences) | 被引量 : 0次 | 上传用户:hustsmes
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
Although a number of petrographic observations and isotopic data suggest that magma mixing is common in genesis of many granite plutons, it is still controversial whether the mantle-derived magmas were involved in granites. We carried out in this study a systematic analysis of in situ zircon Hf-O isotopes for three early Yanshanian intrusions dated at ca. 160 Ma from the Nanling Range of Southeast China. The Qinghu monzonite has very homogeneous zircon Hf-O isotopic compositions, εHf(t) =11.6±0.3 and δ18O=5.4‰±0.3‰. In combination with whole-rock geochemical and Sr-Nd isotopic data, the parental magma of the Qinghu monzonite were likely derived from the partial melting of recently-metasomatized, phlogopite-bearing lithospheric mantle without appreciable crustal contamination. The Lisong and Fogang granites and the mafic microgranular enclaves (MME) within the Lisong granites have a wide range of zircon Hf-O isotopic compositions, with Hf and O isotopes being negatively correlated within each pluton. The Lisong MMEs were crystallized from a mantle-derived magma, similar to the parental magma of the Qinghu monzonite, with small amount of crustal assimilation. The Lisong and Fogang granites were formed by reworking of meta-sedimentary materials by mantle-derived magmas and mixing of the mantle-and sediment-derived melts to varying degrees. It is thus concluded that these two Yanshanian granites in the Nanling Range were formed associated with growth and differentiation of continental crust. Although a number of petrographic observations and isotopic data suggest that magma mixing is common in genesis of many granite plutons, it is still controversial whether the mantle-derived magmas were involved in granites. We carried out in this study a systematic analysis of in situ zircon Hf-O isotopes for three early Yanshanian intrusions dated at ca. 160 Ma from the Nanling Range of Southeast China. The Qinghu monzonite has very homogeneous zircon Hf-O isotopic compositions, εHf (t) = 11.6 ± 0.3 and δ18O = 5.4 ‰ ± 0.3 ‰. In combination with whole-rock geochemical and Sr-Nd isotopic data, the parental magma of the Qinghu monzonite were likely derived from the partial melting of recently-metasomatized, phlogopite-bearing lithospheric mantle without appreciable crustal contamination. The Lisong and Fogang granites and the mafic microgranular enclaves (MME) within the Lisong granites have a wide range of zircon Hf-O isotopic compositions, with Hf and O isotopes being negatively correlated ed within each pluton. The Lisong and Fogang granites were formed by reworking of meta-sedimentary materials by mantle -derived magmas and mixing of the mantle-and sediment-derived melts to varying degrees. It is thus wire that these two Yanshanian granites in the Nanling Range were formed associated with growth and differentiation of continental crust.
其他文献
我们在做食管充气试验(esophageal insufflation test)时观察到在食管入口下方存在最佳发音位置,自制了经鼻食管上段置管发音器,简称食管音发声器,获得了发音功能,现报告如下。
This paper is trying to analyze the E-C interpreting scripts of Inaugural Address, Remarks on Winning the Nobel Prize and Shanghai Speech by the 44th president
本文简要介绍中国压磁应力计的电磁学和力学原理,地壳岩石中水压重复观测实验结果,以及使用它进行地应力测量的地质力学前提条件。在压磁应力计测量地应力相对变化结果中阐述
近年来,随着高等职业教育改革的推进,大学生的创新精神和科研能力逐渐受到重视。目前,高等职业教育中依然存在学生学习不主动,被迫接受知识的现象。对此,本文以温州科技职业
澳大利亚寒武系集中分布在一南北向分布的从澳大利亚的北部、中部直到南澳大利亚克拉通地块上,少量寒武纪地层分布在新南威尔士、维多利亚和塔斯马尼亚。寒武系的底在中澳大
对于高职教育来说,实践教学环节是其目标培养的重点工作,需要更加重视,本文从课程设置、教学方法以及考核内容等多个方面进行了分析,提出了具体的改革措施。 For higher voc
德国地质研究中心、德国卡尔斯鲁厄理工学院、拜罗伊特大学和美国亚利桑那州立大学的研究人员报告了对下地幔镁方铁矿的研究结果,意外发现地球上地震波的传播并不一致的性质
构建中职与高职衔接的体系是终身教育理念在职业教育系统的实践。酒店管理专业中高职衔接要求中职针对酒店基层服务岗位开设专业基础课程及初级技能课程,高职针对酒店基层管
The effects of excavation unloading, construction reloading and underground water on basal heave of excavation projects were presented and analyzed based on the
对于斜坡稳定性分析与计算理论,提出了尺度因子的概念,分析了在不同尺度因子下斜坡的稳定性系数以及斜坡推力的变化规律,并分别建立了斜坡稳定性系数随尺度因子变化的线性模