
扬子西缘新元古代盐边群火山岩年代学及大地构造背景
刘佩雯, 张继彪, 丁孝忠, 刘燕学
扬子西缘新元古代盐边群火山岩年代学及大地构造背景
Geochronology and Tectonic Significance of Neoproterozoic Volcanic Rocks from Yanbian Group in Western Yangtze Block
扬子板块西缘新元古代盐边群广泛发育一系列火山岩,其年代学和构造背景对理解扬子板块前寒武纪构造演化具有重要意义.本文获得盐边群乍古组、小坪组、渔门组和荒田组火山岩LA-ICP-MS锆石U-Pb年龄分别为934±5 Ma、863±4 Ma、843±7 Ma和797±9 Ma,精确限制了盐边群时代为934~797 Ma.荒田组玄武岩属于钙碱性N-MORB(正常型洋中脊玄武岩)系列,轻稀土相对亏损、重稀土相对富集,具有中等程度的Nb、Ta负异常和轻微的Ti负异常,ε Nd(t)值为3.8~4.9.荒田组玄武岩来自以石榴子石和尖晶石为稳定区的地幔橄榄岩10%~20%的部分熔融.构造背景判别图解指示荒田组玄武岩形成于活动大陆边缘弧前盆地.结合前人的研究成果,认为扬子西缘新元古代早-中期存在弧-盆地系统,扬子板块新元古代构造动力学背景应为活动大陆边缘洋-陆俯冲,板块俯冲开始的时间不晚于934 Ma.
The Neoproterozoic Yanbian volcanic rocks are extensively exposed in the western Yangtze block, providing an ideal opportunity to study the Precambrian tectonic evolution of the Yangtze block. LA-ICP-MS zircon U-Pb dating of Zhagu Formation, Xiaoping Formation, Yumen Formation and Huangtian Formation yielded zircon U-Pb ages of 934±5 Ma, 863±4 Ma, 843±7 Ma and 797±9 Ma, respectively. The N-MORB (normal mid-ocean ridge basalts) type basalts from the Huangtian Formation belong to calc-alkaline series, and display light rare earth element depleted patterns, with moderate negative Nb, Ta anomaly and minor negative Ti anomalies. In addition, these rocks have positive ε Nd(t) values (+3.8 to +4.9). They are suggested to be derived from 10%-20% partial melting of the MORB-like source in a fore-arc basin setting in the garnet+spinel stability field. Combined with previous studies, the data confirm the existence of an arc-trench system in the western Yangtze block in the Neoproterozoic. It proposes that the western Yangtze block was located in a convergent setting during the Neoproterozoic. The subduction of oceanic lithosphere beneath the western margin of the Yangtze block initiated no later than 934 Ma.
扬子西缘 / 盐边群 / 锆石U-Pb年龄 / 地球化学 / 大地构造背景
western Yangtze block / Yanbian Group / zircon U-Pb dating / geochemistry / tectonic setting
P58
Aldanmaz,E.,Pearce,J.A.,Thirlwall,M.F.,et al.,2000.Petrogenetic Evolution of Late Cenozoic,Post-Collision Volcanism in Western Anatolia,Turkey.Journal of Volcanology and Geothermal Research,102(1-2):67-95.https://doi.org/10.1016/s0377-0273(00)00182-7
|
Brewer,T.S.,Åhäll,K.I.,Menuge,J.F.,et al.,2004.Mesoproterozoic Bimodal Volcanism in SW Norway,Evidence for Recurring Pre-Sveconorwegian Continental Margin Tectonism.Precambrian Research,134(3-4):249-273.https://doi.org/10.1016/j.precamres.2004.06.003
|
Bureau of Geology and Mineral Resources Sichuan Province,1991.Regional Geology of Sichuan Province.Geology Publishing House, Beijing (in Chinese).
|
Chen,W.T.,Sun,W.H.,Zhou,M.F.,et al.,2018.Ca.1 050 Ma Intra-Continental Rift-Related A-Type Felsic Rocks in the Southwestern Yangtze Block,South China.Precambrian Research,309:22-44.https://doi.org/10.1016/j.precamres.2017.02.011
|
Cui,X.Z.,Wang,J.,Wang,X.C.,et al.,2021.Early Crustal Evolution of the Yangtze Block:Constraints from Zircon U-Pb-Hf Isotope Systematics of 3.1-1.9 Ga Granitoids in the Cuoke Complex,SW China.Precambrian Research,357:106155.https://doi.org/10.1016/j.precamres.2021.106155
|
Du,L.L.,Geng,Y.S.,Yang,C.H.,et al.,2005.Geochemistry and SHRIMP U-Pb Zircon Chronology of Basalts from the Yanbian Group in the Western Yangtze Block.Acta Geologica Sinica,79(6):805-813 (in Chinese with English abstract).
|
Du,L.L.,Guo,J.H.,Nutman,A.P.,et al.,2014.Implications for Rodinia Reconstructions for the Initiation of Neoproterozoic Subduction at ~860 Ma on the Western Margin of the Yangtze Block:Evidence from the Guandaoshan Pluton.Lithos,(196-197):67-82.https://doi.org/10.1016/j.lithos.2014.03.002
|
Fan,W.M.,Guo,F.,Wang,Y.J.,et al.,2001.Post-Orogenic Bimodal Volcanism along the Sulu Orogenic Belt in Eastern China.Physics and Chemistry of the Earth,Part A:Solid Earth and Geodesy,26(9-10):733-746.https://doi.org/10.1016/s1464-1895(01)00123-5
|
Fan,W.M.,Guo,F.,Wang,Y.J.,et al.,2004.Late Mesozoic Volcanism in the Northern Huaiyang Tectono-Magmatic Belt,Central China:Partial Melts from a Lithospheric Mantle with Subducted Continental Crust Relicts beneath the Dabie Orogen? Chemical Geology,209(1-2):27-48.https://doi.org/10.1016/j.chemgeo.2004.04.020
|
Geng,Y.S.,Kuang,H.W.,Liu,Y.Q.,et al.,2017.Subdivision and Correlation of the Mesoproterozoic Stratigraphy in the Western and Northern Margins of Yangtze Block.Acta Geologica Sinica,91(10):2151-2174 (in Chinese with English abstract).
|
Geng,Y.S.,Yang,C.H.,Wang,X.S.,et al.,2008.Evolution of Metamorphic Basement in Western Margin of Yangtze Craton.China University of Geosciences Press,Beijing(in Chinese).
|
George,R.,Turner,S.,Hawkesworth,C.,et al.,2003.Melting Processes and Fluid and Sediment Transport Rates along the Alaska-Aleutian Arc from an Integrated U-Th-Ra-Be Isotope Study.Journal of Geophysical Research:Solid Earth,108(B5):2252.https://doi.org/10.1029/2002jb001916
|
Greentree,M.R.,Li,Z.X.,Li,X.H.,et al.,2006.Late Mesoproterozoic to Earliest Neoproterozoic Basin Record of the Sibao Orogenesis in Western South China and Relationship to the Assembly of Rodinia.Precambrian Research,151(1-2):79-100.https://doi.org/10.1016/j.precamres.2006.08.002
|
Guan,J.L.,Zheng,L.L.,Liu,J.H.,et al.,2011.Zircons SHRIMP U-Pb Dating of Diabase from Hekou,Sichuan Province,China and Its Geological Significance.Acta Geologica Sinica,85(4):482-490 (in Chinese with English abstract).
|
Guo,J.L.,Wu,Y.B.,Gao,S.,et al.,2015.Episodic Paleoarchean-Paleoproterozoic (3.3-2.0 Ga) Granitoid Magmatism in Yangtze Craton,South China:Implications for Late Archean Tectonics.Precambrian Research,270:246-266.https://doi.org/10.1016/j.precamres.2015.09.007
|
Hu,P.Y.,Zhai,Q.G.,Wang,J.,et al.,2020.U-Pb Zircon Geochronology,Geochemistry,and Sr-Nd-Hf-O Isotopic Study of Middle Neoproterozoic Magmatic Rocks in the Kangdian Rift,South China:Slab Rollback and Backarc Extension at the Northwestern Edge of the Rodinia.Precambrian Research,347:105863.https://doi.org/10.1016/j.precamres.2020.105863
|
Li,H.K.,Zhang,C.L.,Yao,C.Y.,et al.,2013.U-Pb Zircon Age and Hf Isotope Compositions of Mesoproterozoic Sedimentary Strata on the Western Margin of the Yangtze Massif.Science China Earth Sciences,56(4):628-639.https://doi.org/10.1007/s11430-013-4590-9
|
Li,Q.W.,Zhao,J.H.,2018.The Neoproterozoic High-Mg Dioritic Dikes in South China Formed by High Pressures Fractional Crystallization of Hydrous Basaltic Melts. Precambrian Research,309: 198-211.
|
Li,X.H.,1999.U-Pb Zircon Ages of Granites from the Southern Margin of the Yangtze Block:Timing of Neoproterozoic Jinning:Orogeny in SE China and Implications for Rodinia Assembly.Precambrian Research,97(1-2):43-57.https://doi.org/10.1016/s0301-9268(99)00020-0
|
Li,X.H.,Li,Z.X.,Sinclair,J.A.,et al.,2006.Revisiting the “Yanbian Terrane”:Implications for Neoproterozoic Tectonic Evolution of the Western Yangtze Block,South China.Precambrian Research,151(1-2):14-30.https://doi.org/10.1016/j.precamres.2006.07.009
|
Liu,H.,Zhao,J.H.,2019.Slab Breakoff beneath the Northern Yangtze Block:Implications from the Neoproterozoic Dahongshan Mafic Intrusions.Lithos,(342-343):263-275.https://doi.org/10.1016/j.lithos.2019.05.037
|
Liu,S.D.,Zeng,Z.X.,Guo,R.L.,et al.,2021.Huashan Group in Northern Margin of Yangtze Block:A Suite of Back-Arc-Basin Volcanic-Sedimentary Strata But not Ophiolite Mélange.Earth Science,46(8):2751-2767 (in Chinese with English abstract).
|
Ludwig,K.R.,2003.ISOPLOT 3.0:A Geochronological Toolkit for Microsoft Excel.Berkeley Geochronology Center, Special Publication,No.4.
|
Luo,B.J.,Liu,R.,Zhang,H.F.,et al.,2018.Neoproterozoic Continental Back-Arc Rift Development in the Northwestern Yangtze Block:Evidence from the Hannan Intrusive Magmatism.Gondwana Research,59:27-42.https://doi.org/10.1016/j.gr.2018.03.012
|
Pearce,J.A.,Cann,J.R.,1973.Tectonic Setting of Basic Volcanic Rocks Determined Using Trace Element Analyses.Earth and Planetary Science Letters,19(2):290-300.https://doi.org/10.1016/0012-821x(73)90129-5
|
Reagan,M.K.,Ishizuka,O.,Stern,R.J.,et al.,2010.Fore-Arc Basalts and Subduction Initiation in the Izu-Bonin-Mariana System.Geochemistry,Geophysics,Geosystems,11(3).https://doi.org/10.1029/2009gc002871
|
Sun,S.S.,McDonough,W.F.,1989.Chemical and Isotopic Systematics of Oceanic Basalts:Implications for Mantle Composition and Processes.Geological Society,London,Special Publications,42(1):313-345.https://doi.org/10.1144/gsl.sp.1989.042.01.19
|
Sun,W.H.,Zhou,M.F.,Gao,J.F.,et al.,2009.Detrital Zircon U-Pb Geochronological and Lu-Hf Isotopic Constraints on the Precambrian Magmatic and Crustal Evolution of the Western Yangtze Block,SW China.Precambrian Research,172(1-2):99-126.https://doi.org/10.1016/j.precamres.2009.03.010
|
Tian,L.Y.,Castillo,P.R.,Hawkins,J.W.,et al.,2008.Major and Trace Element and Sr-Nd Isotope Signatures of Lavas from the Central Lau Basin:Implications for the Nature and Influence of Subduction Components in the Back-Arc Mantle.Journal of Volcanology and Geothermal Research,178(4):657-670.https://doi.org/10.1016/j.jvolgeores.2008.06.039
|
Ukstins,I.A.,Renne,P.R.,Wolfenden,E.,et al.,2002.Matching Conjugate Volcanic Rifted Margins:40Ar/39Ar Chrono-Stratigraphy of Pre- and Syn-Rift Bimodal Flood Volcanism in Ethiopia and Yemen.Earth and Planetary Science Letters,198(3-4):289-306.https://doi.org/10.1016/s0012-821x(02)00525-3
|
Wang,D.B.,Sun,Z.M.,Yin,F.G.,et al.,2012.Geochronology of the Hekou Group on the Western Margin of the Yangtze Block:Evidence from Zircon LA-ICP-MS U-Pb Dating of Volcanic Rocks.Journal of Stratigraphy,36(3):630-635 (in Chinese with English abstract).
|
Winchester,J.A.,Floyd,P.A.,1976.Geochemical Magma Type Discrimination:Application to Altered and Metamorphosed Basic Igneous Rocks.Earth and Planetary Science Letters,28(3):459-469.https://doi.org/10.1016/0012-821x(76)90207-7
|
Wu,Y.B.,Zhou,G.Y.,Gao,S.,et al.,2014.Petrogenesis of Neoarchean TTG Rocks in the Yangtze Craton and Its Implication for the Formation of Archean TTGS.Precambrian Research,254:73-86.https://doi.org/10.1016/j.precamres.2014.08.004
|
Yang,H.,Liu,F.L.,Liu,P.H.,et al.,2013.40Ar-39Ar dating for Muscovite in Garnet Muscovite-Felsic Schists of the Dahongshan Group in Southwestern Yangtze Block and Its Geological Significance.Acta Petrologica Sinica,29(6):2161-2170 (in Chinese with English abstract).
|
Yao,J.L.,Shu,L.S.,Santosh,M.,et al.,2015.Neoproterozoic Arc-Related Andesite and Orogeny-Related Unconformity in the Eastern Jiangnan Orogenic Belt:Constraints on the Assembly of the Yangtze and Cathaysia Blocks in South China.Precambrian Research,262:84-100.https://doi.org/10.1016/j.precamres.2015.02.021
|
Yin,F.G.,Sun,Z.M.,Zhang,Z.,2011.Mesoproterozoic Stratigraphic-Structure Framework in Huili-Dongchuan Area. Geological Review,57(6):770-778 (in Chinese with English abstract).
|
Zhang,J.B.,Ding,X.Z.,Liu,Y.X.,2021.Neoproterozoic Tectonic Switch on the Southwestern Yangtze Block:Evidence from Zircon U-Pb-Hf Isotopes and Geochemistry of the A- and I-Type Granites.International Geology Review,63(18):2338-2355.https://doi.org/10.1080/00206814.2020.1836681
|
Zhang,J.B.,Ding,X.Z.,Liu,Y.X.,et al.,2020.Geochronology and Geological Implication in Two Episodes of Meso-Neoproterozoic Magmatism in the Southwestern Yangtze Block.Earth Science,45(7):2452-2468 (in Chinese with English abstract).
|
Zhang,Y.Z.,Wang,Y.J.,Geng,H.Y.,et al.,2013.Early Neoproterozoic (∼850 Ma) Back-Arc Basin in the Central Jiangnan Orogen (Eastern South China):Geochronological and Petrogenetic Constraints from Meta-Basalts.Precambrian Research,231:325-342.https://doi.org/10.1016/j.precamres.2013.03.016
|
Zhao,J.H.,Li,Q.W.,Liu,H.,et al.,2018.Neoproterozoic Magmatism in the Western and Northern Margins of the Yangtze Block (South China) Controlled by Slab Subduction and Subduction-Transform-Edge-Propagator.Earth-Science Reviews,187:1-18.https://doi.org/10.1016/j.earscirev.2018.10.004
|
Zhao,J.H.,Zhou,M.F.,2007.Neoproterozoic Adakitic Plutons and Arc Magmatism along the Western Margin of the Yangtze Block,South China.The Journal of Geology,115(6):675-689.https://doi.org/10.1086/521610
|
Zhao,J.H.,Zhou,M.F.,Wu,Y.B.,et al.,2019.Coupled Evolution of Neoproterozoic Arc Mafic Magmatism and Mantle Wedge in the Western Margin of the South China Craton.Contributions to Mineralogy and Petrology,174(4):1-16.https://doi.org/10.1007/s00410-019-1573-7
|
Zhao,X.F.,Zhou,M.F.,Li,J.W.,et al.,2010.Late Paleoproterozoic to Early Mesoproterozoic Dongchuan Group in Yunnan,SW China:Implications for Tectonic Evolution of the Yangtze Block.Precambrian Research,182(1-2):57-69.https://doi.org/10.1016/j.precamres.2010.06.021
|
Zheng,Y.F.,Gong,B.,Zhao,Z.F.,et al.,2008.Zircon U-Pb Age and O Isotope Evidence for Neoproterozoic Low-18O Magmatism during Supercontinental Rifting in South China:Implications for the Snowball Earth Event.American Journal of Science,308(4):484-516.https://doi.org/10.2475/04.2008.04
|
Zhou,M.F.,Ma,Y.X.,Yan,D.P.,et al.,2006a.The Yanbian Terrane (Southern Sichuan Province,SW China):A Neoproterozoic Arc Assemblage in the Western Margin of the Yangtze Block.Precambrian Research,144(1-2):19-38.https://doi.org/10.1016/j.precamres.2005.11.002
|
Zhou,M.F.,Yan,D.P.,Wang,C.L.,et al.,2006b.Subduction-Related Origin of the 750 Ma Xuelongbao Adakitic Complex (Sichuan Province,China):Implications for the Tectonic Setting of the Giant Neoproterozoic Magmatic Event in South China.Earth and Planetary Science Letters,248(1-2):286-300.https://doi.org/10.1016/j.epsl.2006.05.032
|
Zhou,M.F.,Yan,D.P.,Kennedy,A.K.,et al.,2002.SHRIMP U-Pb Zircon Geochronological and Geochemical Evidence for Neoproterozoic Arc-Magmatism along the Western Margin of the Yangtze Block,South China.Earth and Planetary Science Letters,196(1-2):51-67.https://doi.org/10.1016/S0012-821x(01)00595-7
|
Zhu,W.G.,Zhong,H.,Li,Z.X.,et al.,2016.SIMS Zircon U-Pb Ages,Geochemistry and Nd-Hf Isotopes of ca.1.0 Ga Mafic Dykes and Volcanic Rocks in the Huili Area,SW China:Origin and Tectonic Significance.Precambrian Research,273:67-89.https://doi.org/10.1016/j.precamres.2015.12.011
|
Zhu,Y.,Lai,S.C.,Qin,J.F.,et al.,2019a.Petrogenesis and Geodynamic Implications of Neoproterozoic Gabbro-Diorites,Adakitic Granites,and A-Type Granites in the Southwestern Margin of the Yangtze Block,South China.Journal of Asian Earth Sciences,183:103977.https://doi.org/10.1016/j.jseaes.2019.103977
|
Zhu,Y.,Lai,S.C.,Qin,J.F.,et al.,2019b.Geochemistry and Zircon U-Pb-Hf Isotopes of the 780 Ma I-Type Granites in the Western Yangtze Block:Petrogenesis and Crustal Evolution.International Geology Review,61(10):1222-1243.https://doi.org/10.1080/00206814.2018.1504330
|
杜利林,耿元生,杨崇辉,等,2005.扬子地台西缘盐边群玄武质岩石地球化学特征及SHRIMP锆石U-Pb年龄.地质学报,79(6):805-813.
|
耿元生,旷红伟,柳永清,等,2017.扬子地块西、北缘中元古代地层的划分与对比.地质学报,91(10):2151-2174.
|
耿元生,杨崇辉,王新社等,2008.扬子地台西缘变质基底演化.北京:地大彩印厂.
|
关俊雷,郑来林,刘建辉,等,2011.四川省会理县河口地区辉绿岩体的锆石SHRIMP U-Pb年龄及其地质意义.地质学报,85(4):482-490.
|
刘述德,曾佐勋,郭瑞禄,等,2021.扬子陆块北缘花山群:弧后盆地火山-沉积岩系而非蛇绿混杂岩.地球科学,46(8):2751-2767.
|
四川省地质矿产局,1991.四川省区域地质志.北京:地质出版社.
|
王冬兵,孙志明,尹福光,等,2012.扬子地块西缘河口群的时代:来自火山岩锆石LA-ICP-MS U-Pb年龄的证据.地层学杂志,36(3):630-635.
|
杨红,刘福来,刘平华,等,2013.扬子地块西南缘大红山群石榴白云母-长石石英片岩的白云母40Ar-39Ar定年及其地质意义.岩石学报,29(6):2161-2170.
|
尹福光,孙志明,张璋,2011.会理-东川地区中元古代地层-构造格架.地质论评,57(6):770-778.
|
张继彪,丁孝忠,刘燕学,等,2020.扬子西南缘中-新元古代两期岩浆活动年代学及地质意义.地球科学,45(7):2452-2468.
|
本文由中国地质调查局地质调查项目《全国陆域及海区地质图件更新与共享》(DD20221645)以及《江南造山带区域地质调查片区总结与服务产品开发(121201111120117)所支持.野外工作获得任光明教授级高工的帮助,在此一并感谢.
/
〈 |
|
〉 |