IOCAS-IR  > 深海极端环境与生命过程研究中心
Iron isotopic composition of supra-subduction zone ophiolitic peridotite from northern Tibet
Zhang, Long1; Sun, Wei-dong2,3,4; Zhang, Zhaofeng5; An, Yajun5; Liu, Fang5
2019-08-01
Source PublicationGEOCHIMICA ET COSMOCHIMICA ACTA
ISSN0016-7037
Volume258Pages:274-289
Corresponding AuthorZhang, Long(zhanglong@gig.ac.cn) ; Sun, Wei-dong(weidongsun@qdio.ac.cn)
AbstractWe present high-precision iron isotope data for harzburgites and constituting minerals from the Yushigou suprasubduction zone ophiolite in the North Qilian orogen of northern Tibet to provide insights into iron isotope behavior in subduction zones. The Yushigou harzburgites represent typical melting residues of silica-enriched forearc mantle wedge with significant melt extraction and minimal melt percolation. The delta Fe-56 ranges from -0.096% to 0.110% in olivine, from -0.111% to 0.105% in orthopyroxene and from -0.141% to 0.054% in spinel. Coexisting minerals fall on a line with a slope of 1 in the delta-delta plot, indicating iron isotope equilibrium between mineral pairs. Iron isotopic fractionation between olivine and orthopyroxene is minor, which is consistent with theoretical predictions and previous observations. Good iron isotopic equilibrium between olivine and orthopyroxene is a further indicator that silica enrichment in arc peridotites is inherited from their mantle source. In contrast, significantly negative iron isotopic fractionation between spinel and olivine contradicts with most previous constraints, which may be ascribed to Cr substitution in spinel. Bulk rock harzburgites have delta Fe-56 ranging from -0.097% to 0.076%, the average of which (0.002 +/- 0.020%) is similar to average delta Fe-56 determined for abyssal peridotites. Based on this inference, the lower delta Fe-56 of arc magmas than MORB should be due to smaller discrepancy in Fe3+/RFe between arc magmas and arc peridotites when compared with MORB and abyssal peridotites. Our modelling demonstrates that this can be achieved if arc magmas are produced by redox-buffered melting of silica-enriched mantle wedge while MORB are produced by redox-unbuffered melting of the depleted mantle. (C) 2019 Elsevier Ltd. All rights reserved.
KeywordIron isotopes Mantle wedge Peridotite Subduction zone North Qilian
DOI10.1016/j.gca.2019.04.031
Indexed BySCI
Language英语
Funding ProjectStrategic Priority Research Program of the Chinese Academy of Sciences[XDB18000000] ; National Key R&D Program of China[2016YFC0600408] ; China Postdoctoral Science Foundation[2016LH00023]
WOS Research AreaGeochemistry & Geophysics
WOS SubjectGeochemistry & Geophysics
WOS IDWOS:000472708700017
PublisherPERGAMON-ELSEVIER SCIENCE LTD
Citation statistics
Cited Times:1[WOS]   [WOS Record]     [Related Records in WOS]
Document Type期刊论文
Identifierhttp://ir.qdio.ac.cn/handle/337002/161841
Collection深海极端环境与生命过程研究中心
Corresponding AuthorZhang, Long; Sun, Wei-dong
Affiliation1.Chinese Acad Sci, Guangzhou Inst Geochem, CAS Key Lab Mineral & Metallogeny, Guangzhou 510640, Guangdong, Peoples R China
2.Chinese Acad Sci, Ctr Deep Sea Res, Inst Oceanol, Qingdao 266071, Shandong, Peoples R China
3.Qingdao Natl Lab Marine Sci & Technol, Lab Marine Mineral Resources, Qingdao 266237, Shandong, Peoples R China
4.Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China
5.Chinese Acad Sci, Guangzhou Inst Geochem, State Key Lab Isotope Geochem, Guangzhou 510640, Guangdong, Peoples R China
Corresponding Author AffilicationInstitute of Oceanology, Chinese Academy of Sciences
Recommended Citation
GB/T 7714
Zhang, Long,Sun, Wei-dong,Zhang, Zhaofeng,et al. Iron isotopic composition of supra-subduction zone ophiolitic peridotite from northern Tibet[J]. GEOCHIMICA ET COSMOCHIMICA ACTA,2019,258:274-289.
APA Zhang, Long,Sun, Wei-dong,Zhang, Zhaofeng,An, Yajun,&Liu, Fang.(2019).Iron isotopic composition of supra-subduction zone ophiolitic peridotite from northern Tibet.GEOCHIMICA ET COSMOCHIMICA ACTA,258,274-289.
MLA Zhang, Long,et al."Iron isotopic composition of supra-subduction zone ophiolitic peridotite from northern Tibet".GEOCHIMICA ET COSMOCHIMICA ACTA 258(2019):274-289.
Files in This Item:
There are no files associated with this item.
Related Services
Recommend this item
Bookmark
Usage statistics
Export to Endnote
Google Scholar
Similar articles in Google Scholar
[Zhang, Long]'s Articles
[Sun, Wei-dong]'s Articles
[Zhang, Zhaofeng]'s Articles
Baidu academic
Similar articles in Baidu academic
[Zhang, Long]'s Articles
[Sun, Wei-dong]'s Articles
[Zhang, Zhaofeng]'s Articles
Bing Scholar
Similar articles in Bing Scholar
[Zhang, Long]'s Articles
[Sun, Wei-dong]'s Articles
[Zhang, Zhaofeng]'s Articles
Terms of Use
No data!
Social Bookmark/Share
All comments (0)
No comment.
 

Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.