Geochemistry of Early Cretaceous Intermediate to Mafic Dikes in the Jiaodong Peninsula: Constraints on Mantle Source Composition beneath Eastern China
| Autor: | Wolfgang Siebel, Qun Long, Rong Hu, Shu Zhou, Yi-Zeng Yang, Chun-Yue Yang, Fukun Chen |
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| Rok vydání: | 2017 |
| Předmět: |
Dike
geography geography.geographical_feature_category Radiogenic nuclide 010504 meteorology & atmospheric sciences Metamorphic rock Geochemistry Geology 010502 geochemistry & geophysics 01 natural sciences Mantle (geology) Cretaceous Mafic Shandong peninsula 0105 earth and related environmental sciences Zircon |
| Zdroj: | The Journal of Geology. 125:713-732 |
| ISSN: | 1537-5269 0022-1376 |
| Popis: | The Jiaodong Peninsula of eastern Shandong Province comprises the Jiaobei terrain of North China affinity and the Sulu ultrahigh-pressure metamorphic terrain. In this study, we present zircon U-Pb ages, major- and trace-element data, and Sr-Nd-Pb isotopic compositions of intermediate to mafic dikes from the Linglong region of the Jiaobei terrain and the Rushan region of the Sulu terrain to discuss the nature of the mantle source(s) beneath eastern China during the Early Cretaceous. Zircon U-Pb dating yields Early Cretaceous dike emplacement ages ranging from ∼124 to ∼120 Ma for the Linglong region and from ∼118 to ∼108 Ma for the Rushan region. Dikes from both regions are all potassic, with “arc-like” trace-element distributions as well as high unradiogenic Pb isotopic composition, low initial eNd values (−19.64 to −10.80), and high radiogenic 87Sr/86Sr ratios (0.7075–0.7112), suggesting the involvement of an extensively enriched mantle component. Such isotopic characteristics are found in contemp... |
| Databáze: | OpenAIRE |
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