Geological magazine, 2019-12, Vol.156 (12), p.1965-1981
2019
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- Autor(en) / Beteiligte
- Titel
- Petrogenesis of high Ba-Sr plutons with high Sr/Y ratios in an intracontinental setting; evidence from Early Cretaceous Fushan monzonites, central North China Craton
- Ist Teil von
- Geological magazine, 2019-12, Vol.156 (12), p.1965-1981
- Ort / Verlag
- Cambridge: Cambridge University Press
- Erscheinungsjahr
- 2019
- Quelle
- Alma/SFX Local Collection
- Beschreibungen/Notizen
- Geochronological, major and trace element, and Sr-Nd-Hf isotopic data are reported for the monzonitic rocks of the Fushan pluton in the Taihang Mountains, central North China Craton, in order to investigate their sources, petrogenesis and tectonic implications. Zircon U-Pb dating results reveal that the Fushan pluton was emplaced during the Early Cretaceous (∼126-124 Ma). The monzonites and quartz monzonites are mainly characterized by calc-alkaline and magnesian features and display light rare earth element (LREE) enrichment and flat heavy REE (HREE) patterns with slightly positive Eu anomalies. They have similar whole-rock initial 87Sr/86Sr ratios (0.70653-0.70819), εNd(t) values (-13.6 to -18.6) and zircon εHf(t) values (-21.8 to -17.3). The primary magma of the Fushan pluton was derived from the partial melting of a spinel-facies amphibole-bearing ancient enriched lithospheric mantle. The monzonitic rocks also have high Ba-Sr and low Y and Yb contents, with high Sr/Y and La/Yb ratios. These geochemical features of monzonitic rocks are not only inherited from the magma source but also significantly enhanced by crystal fractionation during magmatic evolution; e.g. hornblende fractionation increased the Ba-Sr concentrations and Sr/Y ratios. During the Early Cretaceous, the slab sinking and roll-back of the Palaeo-Pacific Plate could have created an ancient big mantle wedge beneath East Asia and induced a lithospheric extensional process in the central North China Craton within an intracontinental setting.
- Sprache
- Englisch
- Identifikatoren
- ISSN: 0016-7568eISSN: 1469-5081DOI: 10.1017/S0016756819000256Titel-ID: cdi_proquest_journals_2338900389
- Format
- –
- Schlagworte
- absolute age, alkaline earth metals, Anomalies, Asia, Barium, China, Cratons, Cretaceous, crystal fractionation, dates, Earth, Far East, fractional crystallization, Fractionation, Fushan, Fushan Pluton, genesis, Geochemistry, Geochronology, Geology, hafnium, ICP mass spectra, igneous and metamorphic rocks, Igneous rocks, intrusions, Isotopes, Lasers, Lava, Lower Cretaceous, Magma, magma contamination, Mantle, mass spectra, Mesozoic, metals, monzonites, Mountains, neodymium, nesosilicates, North China Platform, orthosilicates, partial melting, Petrogenesis, Petrology, Plates, Plates (tectonics), plutonic rocks, Plutons, Quartz, quartz monzonite, Radiometric dating, Rare earth elements, rare earths, Ratios, Rock, rock, sediment, soil, Rocks, Sedimentary facies, silicates, spectra, Stone, Strontium, Strontium 87, Strontium isotopes, Taihang Mountains, Tectonics, Trace elements, U/Pb, upper mantle, whole rock, Ytterbium, Yttrium, Zircon, zircon group