File Download
  Links for fulltext
     (May Require Subscription)
Supplementary

Article: The ∼860-Ma, cordilleran-type guandaoshan dioritic pluton in the Yangtze Block, SW China: Implications for the origin of neoproterozoic magmatism

TitleThe ∼860-Ma, cordilleran-type guandaoshan dioritic pluton in the Yangtze Block, SW China: Implications for the origin of neoproterozoic magmatism
Authors
KeywordsEarth sciences
Geology
Issue Date2008
PublisherUniversity of Chicago Press. The Journal's web site is located at http://www.journals.uchicago.edu/JG
Citation
Journal Of Geology, 2008, v. 116 n. 3, p. 238-253 How to Cite?
AbstractThe tectonic setting of the widespread Neoproterozoic igneous rocks in South China has long been a matter of debate. Situated in the western margin of the Yangtze Block of South China, the Guandaoshan pluton is composed of diorite in the core and quartz diorite in the margin. Both types contain abundant mafic enclaves and mafic dikes. This pluton is dated at 858 ± 7 Ma by the SHRIMP zircon U-Pb method. The rocks have SiO 2 contents of 52.8-63.8 wt%, Al 2O 3 contents of 17.4-20.6 wt%, Na 2O contents of 2.14-3.74 wt%, and K 2O contents of 0.44-1.61 wt%. They are calcalkaline with an Al saturation index, A/CNK < 1 (molar Al 2O 3/[CaO + Na 2O + K 2O]) and A/NK> 1, and they have Fe numbers <0.8 (Fe 2O 3/[Fe 2O 3 + MgO]). Their total rare earth element (REE) contents range from 19 to 45 ppm, with concave chondrite-normalized patterns slightly depleted in middle REEs, indicating extensive amphibole fractionation. Their whole-rock ε Nd(t) values range from +3.9 to +5.1, and initial 87Sr/ 86Sr ratios range from 0.7028 to 0.7033. They have zircon ε Hf(t) values ranging from +11 to +17, with mean Hf model ages of around 860 Ma, clearly indicating a depleted-mantle source. In the primitive mantle-normalized trace element spider diagram, the rocks show pronounced enrichment of Rb, Ba, Th, and Pb and depletion of Nb, Ta, and Ti, a typical arc signature. The Guandaoshan pluton is an amphibole-rich, calc-alkaline, Cordilleran-type granitoid, a typical product of subduction-zone magmatism. The occurrence of this Neoproterozoic Cordilleran-type granitoid suggests that the western margin of the Yangtze Block was an Andean-type continental margin at that time, rather than mantle plume-related rifting setting. © 2008 by The University of Chicago. All rights reserved.
Persistent Identifierhttp://hdl.handle.net/10722/57264
ISSN
2023 Impact Factor: 1.5
2023 SCImago Journal Rankings: 0.450
ISI Accession Number ID
References

 

DC FieldValueLanguage
dc.contributor.authorSun, WHen_HK
dc.contributor.authorZhou, MFen_HK
dc.date.accessioned2010-04-12T01:31:15Z-
dc.date.available2010-04-12T01:31:15Z-
dc.date.issued2008en_HK
dc.identifier.citationJournal Of Geology, 2008, v. 116 n. 3, p. 238-253en_HK
dc.identifier.issn0022-1376en_HK
dc.identifier.urihttp://hdl.handle.net/10722/57264-
dc.description.abstractThe tectonic setting of the widespread Neoproterozoic igneous rocks in South China has long been a matter of debate. Situated in the western margin of the Yangtze Block of South China, the Guandaoshan pluton is composed of diorite in the core and quartz diorite in the margin. Both types contain abundant mafic enclaves and mafic dikes. This pluton is dated at 858 ± 7 Ma by the SHRIMP zircon U-Pb method. The rocks have SiO 2 contents of 52.8-63.8 wt%, Al 2O 3 contents of 17.4-20.6 wt%, Na 2O contents of 2.14-3.74 wt%, and K 2O contents of 0.44-1.61 wt%. They are calcalkaline with an Al saturation index, A/CNK < 1 (molar Al 2O 3/[CaO + Na 2O + K 2O]) and A/NK> 1, and they have Fe numbers <0.8 (Fe 2O 3/[Fe 2O 3 + MgO]). Their total rare earth element (REE) contents range from 19 to 45 ppm, with concave chondrite-normalized patterns slightly depleted in middle REEs, indicating extensive amphibole fractionation. Their whole-rock ε Nd(t) values range from +3.9 to +5.1, and initial 87Sr/ 86Sr ratios range from 0.7028 to 0.7033. They have zircon ε Hf(t) values ranging from +11 to +17, with mean Hf model ages of around 860 Ma, clearly indicating a depleted-mantle source. In the primitive mantle-normalized trace element spider diagram, the rocks show pronounced enrichment of Rb, Ba, Th, and Pb and depletion of Nb, Ta, and Ti, a typical arc signature. The Guandaoshan pluton is an amphibole-rich, calc-alkaline, Cordilleran-type granitoid, a typical product of subduction-zone magmatism. The occurrence of this Neoproterozoic Cordilleran-type granitoid suggests that the western margin of the Yangtze Block was an Andean-type continental margin at that time, rather than mantle plume-related rifting setting. © 2008 by The University of Chicago. All rights reserved.en_HK
dc.languageengen_HK
dc.publisherUniversity of Chicago Press. The Journal's web site is located at http://www.journals.uchicago.edu/JGen_HK
dc.relation.ispartofJournal of Geologyen_HK
dc.rightsThe Journal of Geology. Copyright © University of Chicago Press.en_HK
dc.subjectEarth sciencesen_HK
dc.subjectGeologyen_HK
dc.titleThe ∼860-Ma, cordilleran-type guandaoshan dioritic pluton in the Yangtze Block, SW China: Implications for the origin of neoproterozoic magmatismen_HK
dc.typeArticleen_HK
dc.identifier.openurlhttp://library.hku.hk:4550/resserv?sid=HKU:IR&issn=0022-1376&volume=116&issue=3&spage=238&epage=253&date=2008&atitle=The+∼860-Ma,+Cordilleran-type+Guandaoshan+dioritic+pluton+in+the+Yangtze+Block,+SW+China:+implications+for+the+origin+of+neoproterozoic+magmatismen_HK
dc.identifier.emailZhou, MF:mfzhou@hkucc.hku.hken_HK
dc.identifier.authorityZhou, MF=rp00844en_HK
dc.description.naturepublished_or_final_versionen_HK
dc.identifier.doi10.1086/587881en_HK
dc.identifier.scopuseid_2-s2.0-44149087877en_HK
dc.identifier.hkuros142478en_HK
dc.relation.referenceshttp://www.scopus.com/mlt/select.url?eid=2-s2.0-44149087877&selection=ref&src=s&origin=recordpageen_HK
dc.identifier.volume116en_HK
dc.identifier.issue3en_HK
dc.identifier.spage238en_HK
dc.identifier.epage253en_HK
dc.identifier.isiWOS:000255429100002-
dc.publisher.placeUnited Statesen_HK
dc.identifier.scopusauthoridSun, WH=7404011340en_HK
dc.identifier.scopusauthoridZhou, MF=7403506005en_HK
dc.identifier.issnl0022-1376-

Export via OAI-PMH Interface in XML Formats


OR


Export to Other Non-XML Formats