کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5786172 1640337 2017 14 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Full length ArticleMelt inclusions in the olivine from the Nantianwan intrusion: Implications for the parental magma of Ni-Cu-(PGE) sulfide-bearing mafic-ultramafic intrusions of the ∼260 Ma Emeishan large igneous province (SW China)
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات زمین شناسی
پیش نمایش صفحه اول مقاله
Full length ArticleMelt inclusions in the olivine from the Nantianwan intrusion: Implications for the parental magma of Ni-Cu-(PGE) sulfide-bearing mafic-ultramafic intrusions of the ∼260 Ma Emeishan large igneous province (SW China)
چکیده انگلیسی


- Pb isotopic compositions of melt inclusion of the Nantianwan intrusion were reported.
- The parental magma of the Nantianwan intrusion has a high-Mg basaltic composition.
- The intrusion represents the parental magma of sulfide-bearing intrusions in ELIP.

Olivine-hosted melt inclusions provide an archive of the parental magma and early magma history that is unavailable from bulk-rock analyses of cumulates. For those olivine-bearing mafic-ultramafic intrusions, a combined in situ analysis of major elements and Pb isotopic compositions for the melt inclusions and host olivine crystals may provide an effective way to understand the nature of the parental magma of the intrusions. In this study, we take the Nantianwan intrusion in the Emeishan large igneous province (SW China) as an example to analyze the melt inclusions and the host olivine. The Nantianwan intrusion is mainly composed of gabbronorite, with minor olivine gabbro. The olivine crystals in the olivine gabbro have Fo contents varying from 81.1 to 89.2 and Ni from 0.05 to 0.30 wt.%. The melt inclusion hosted in the most Mg-rich olivine has 50.9 wt.% SiO2, 1.0 wt.% TiO2, 15.1 wt.% MgO and 2.9 wt.% Na2O + K2O, indicating that the parental magma of the intrusion was of high-Mg basaltic composition. The melt inclusions overall have 208Pb/206Pb ratios of 2.0567-2.1032 and 207Pb/206Pb of 0.8287-0.8481, similar to the Pb isotopic compositions of the Emeishan flood basalts and consistent with insignificant crustal contamination. Given that the Nantianwan intrusion contains the most Mg-rich olivine among the Ni-Cu-(PGE) sulfide-bearing mafic-ultramafic intrusions in the Emeishan LIP, we infer that the composition of the melt inclusion in the most Mg-rich olivine from the Nantianwan intrusion may represent the least evolved parental magma of the Ni-Cu-(PGE) sulfide-bearing mafic-ultramafic intrusions in the Emeishan LIP. This can be further used to constrain the magma process related to Ni-Cu-(PGE) sulfide mineralization.

201

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Asian Earth Sciences - Volume 134, February 2017, Pages 72-85
نویسندگان
, , ,