Show simple item record

dc.contributor.authorTang, G.
dc.contributor.authorWyman, D.
dc.contributor.authorWang, Q.
dc.contributor.authorLi, J.
dc.contributor.authorLi, Zheng-Xiang
dc.contributor.authorZhao, Z.
dc.contributor.authorSun, W.
dc.date.accessioned2017-01-30T11:27:07Z
dc.date.available2017-01-30T11:27:07Z
dc.date.created2013-03-17T20:00:35Z
dc.date.issued2012
dc.identifier.citationTang, Gong-Jian and Wyman, Derek A. and Wang, Qiang and Li, Jie and Li, Zheng-Xiang and Zhao, Zhen-Hua and Sun, Wei-Dong. 2012. Asthenosphere–lithosphere interaction triggered by a slab window during ridge subduction: Trace element and Sr–Nd–Hf–Os isotopic evidence from Late Carboniferous tholeiites in the western Junggar area (NW China). Earth and Planetary Science Letters. 329-330: pp. 84-96.
dc.identifier.urihttp://hdl.handle.net/20.500.11937/11837
dc.identifier.doi10.1016/j.epsl.2012.02.009
dc.description.abstract

Tholeiites occur in a variety of geological settings, e.g., mid-ocean ridge, back-arc basin, ocean island, island arc and intra-continent, and their geochemical and isotopic characteristics vary according to the corresponding geodynamic environments. Here we investigated the Hatu tholeiitic basalts and basaltic andesites of the western Junggar region, Central Asian Orogenic Belt (CAOB). LA-ICPMS zircon U–Pb analyses indicate that the Hatu tholeiites were generated in the Late Carboniferous (~315 Ma). All the studied rock samples are characterized by flat rare earth elements pattern on chondrite-normalized plot, and negligible Nb, Ta and Ti anomalies on mid-ocean-ridge basalt normalized plots. They are also characterized by moderate positive εNd(t) (+5.25 to +5.94), εHf(t) (+13.24 to +14.89), highly radiogenic Os isotope compositions (187Os/188Os315Ma=0.1338–0.3547), and relatively low (87Sr/86Sr)i ratios (0.7044 to 0.7048). Taking into account their geological characteristics, the occurrence of nearby ophiolites and the types of contemporaneous magmatic rocks found in the western Junggar region, we propose that the Hatu basalts were generated by slab window-related processes following a spreading ridge subduction beneath the Keramay intraoceanic island arc.During this process, deep and enriched asthenospheric mantle rose to the edge of the subducted oceanic lithosphere, its melts infiltrating the subducted oceanic lithosphere and reacting with peridotites. Therefore, the Hatu tholeiites are interpreted as a result of melting of a mixed mantle source consisting of subducted depleted oceanic lithosphere and a deep, enriched upwelling asthenospheric mantle. Incongruent dynamic melting modeling of trace element compositions indicates that the Hatu basalts could have been derived from large degrees of melting (~10%) of such a mixed mantle source. This newly recognized mechanism is a natural consequence of the diversity of contemporaneous potential mantle sources available in slab window settings.

dc.publisherElsevier Science BV
dc.subjectridge subduction
dc.subjectasthenosphere
dc.subjectslab window
dc.subjecttholeiites
dc.subjectCentral Asian Orogenic Belt
dc.titleAsthenosphere–lithosphere interaction triggered by a slab window during ridge subduction: Trace element and Sr–Nd–Hf–Os isotopic evidence from Late Carboniferous tholeiites in the western Junggar area (NW China)
dc.typeJournal Article
dcterms.source.volume329-330
dcterms.source.startPage84
dcterms.source.endPage96
dcterms.source.issn0012821X
dcterms.source.titleEarth and Planetary Science Letters
curtin.department
curtin.accessStatusFulltext not available


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record