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地质学报  2006 

俯冲板片中微量元素的活动性:西天山榴辉岩相运输脉的制约

, PP. 53-60

Keywords: 元素淋滤,微量元素活动性,高压脉,俯冲带,西天山

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Abstract:

西天山的基性高压变质岩显示互相连接的榴辉岩相脉体网络来源于蓝片岩的进变质脱水作用,通过这些网脉可以洞察在俯冲带高压条件下远程流体流动中的流体-岩石相互作用和元素负载。岩相学证据表明外来流体的渗透作用产生运输脉,而流体持续的沟道式流动导致主岩蓝片岩的淋滤。脉和蓝片岩蚀变带中锂(Li)的含量几乎是蓝片岩主岩中锂的两倍,它支持流体是外部来源的设想。这些流体触发了蓝片岩主岩的榴辉岩化作用而形成蓝片岩蚀变带。由于成脉流体中的微量元素含量低,所以导致与流体发生化学反应的主岩中所有微量元素的强烈淋滤。在此过程中有53%~81%的微量元素被活化,与大离子亲石元素和轻稀土元素的损失相符合,它们的损失量几乎是重稀土元素和高场强元素损失量的两倍。

References

[1]  姜常义,姜寒冰,叶书锋,夏明哲,逯东霞.2005.新疆库鲁克塔格地区二叠纪脉岩群岩石地球化学特征,Nd、Sr、Pb同位素组成与岩石成因.地质学报,79(6):823~832.
[2]  吴华,李华芹,莫新华,陈富文,路远发,梅玉萍,邓岗.2005.新疆哈密白石泉铜镍矿区基性-超基性岩的形成时代及其地质意义.地质学报,79(4):498~502.
[3]  Becker H,Jochum K P,Carlson R W.2000.Trace element fractionation during dehydration of eclogites from high-pressure terranes and the implications for element fluxes in subduction zones.Chemical Geology,163:65~99.
[4]  Davies J H.1999.The role of hydraulic fractures and intermediate-depth earthquakes in generating subduction-zone magmatism.Nature,398:142~145.
[5]  Gao J,Klemd R.2001.Primary fluids entrapped at blueschist to eclogite transition:evidence from the Tianshan meta-subduction complex in northwestern China.Contributions to Mineralogy and Petrology,142:1~14.
[6]  Gao J,Klemd R.2003.Formation of HP-LT rocks and their tectonic implications in the western Tianshan Orogen,NW China:geochemical and age constraints.Lithos,66:1~22.
[7]  Hacker B R,Peacock S M,Abers G A,et al.2003.Subduction factory 2.Are intermediate-depth earthquakes in subducting slabs linked to metamorphic dehydration reactions? Journal of Geophysical Research,108(B1):2030~2046.
[8]  Hofmann A W.1988.Chemical differentiation of the earth:the relationship between mantle,continental crust and oceanic crust.Earth and Planetary Science Letters,90:297~314.
[9]  John T,Scherer E E,Haase K,et al.2004.Trace element fractionation during fluid-induced eclogitization in a subducting slab:trace element and Lu-Hf-Sm-Nd isotope systematics.Earth and Planetary Science Letters.227:441~456.
[10]  Manning C E.2004.The chemistry of subduction-zone fluids.Earth and Planetary Science Letters,223:1~16.
[11]  McCulloch M T,Gamble J A.1991.Geochemical and geodynamical constraints on subduction zone magmatism.Earth and Planetary Science Letters,102:358~374.
[12]  Rudnick R L,Barth M,Horn I,et al.2000.Rutile-bearing refractory eclogites:missing link between continents and depleted mantle.Science,287:278~281.
[13]  Rubatto D,Hermann J.2003.Zircon formation during fluid circulation in eclogites (Monviso,Western Alps):implications for Zr and Hf budget in subduction zones.Geochimica et Cosmochimica Acta,67(12):2173~2187.
[14]  Schmidt M W,Poli S.1998.Experimentally based water budgets for dehydrating slabs and consequences for arc magma generation.Earth and Planetary Science Letters,163:361~379.
[15]  Sun S-S,McDonough W F.1989.Chemical and isotopic systematics of oceanic basalts:implications for mantle composition and processes.In:Saunders A D,Dorry M J,eds.Magmatism in the Ocean Basins.London:Geological Society of London,42:313~345.
[16]  Tatsumi Y,Hamilton D L,Nesbitt R W.1986.Chemical characteristics of fluid phase released from a subducted lithosphere and origin of arc magmas:evidence from high-pressure experiments and natural rocks.Journal of Volcanology and Geothermal Research,29:293~309.
[17]  Tribuzio R,Messiga B,Vannucci R,et al.1996.Rare earth element redistribution during high-pressure low-temperature metamorphism in ophiolitic Fe-gabbros (Liguria,northwestern Italy):implications for light REE mobility in subduction zooes.Geology,24:711~714.
[18]  Volkova N I,Budanov V I.1999.Geochemical discrimination of metabasalt rocks of the Fan-Karategin transitional blueschist/greenschist belt,South Tianshan,Tajikistan:seamount volcanism and accretionary tectonics.Lithos,47:201~216.
[19]  Zack T,Rivers T,Foley S F.2001.Cs-Rb-Ba systematics in phengite and amphibole:an assessment of fluid mobility at 2.0 GPa in eclogites from Trescolmen,Central Alps.Contributions to Mineralogy and Petrology,140:651~669.
[20]  Zhang L,Ellis D J,Williams S,et al.2002b.Ultra-high pressure metamorphism in western Tianshan,China:Part II.Evidence from magnesite in eclogite.American Mineralogist,87:861~866.
[21]  高俊,肖序常,汤耀庆,等.1994.新疆西南天山蓝片岩的变质作用 pTDt 轨迹及构造演化.地质论评,40(6):544~553.
[22]  孙桂华,李锦铁,高立明,杨天南.2005.新疆东部哈尔里克山闪长岩锆石SHRIMP U_Pb定年及其地质意义.地质论评,51(4):463~469.
[23]  Becker H,Jochum K P,Carlson R W.1999.Constraints from high-pressure veins in eclogites on the composition of hydrous fluids in subduction zones.Chemical Geology,160:291~308.
[24]  Boynton W V.1984.Geochemistry of the rare earth elements:meteorite studies.In:Henderson P,Ed.Rare Earth Element Geochemistry.New York:Elsevier,63~114.
[25]  Chan L H,Alt J C,Teagle D A H.2002.Lithium and lithium isotope profiles through the upper oceanic crust:a study of seawater-basalt exchange at ODP Sites 504B and 896A.Earth and Planetary Science Letters,201:187~201.
[26]  Gao J,He G,Li M,et al.1995.The mineralogy,petrology,metamorphic PTDt trajectory and exhumation mechanism of blueschists,south Tianshan,northwestern China.Tectonophysics,250:151~168.
[27]  Gao J,Klemd R,Zhang L,et al.1999.P-T path of high-pressure/low-temperaturerocks and tectonic implications in the western Tianshan Mountains,NW China.Journal of Metamorphic Geology,17:621~636.
[28]  Gao J,Xiao W,Li J,et al.2002.\'Central-Asia type\' Orogenesis and Metallogenesis in western China.IGCP-420 Workshop,August 5-14,Changchun,China,Abstracts and excursion guidebook,39.
[29]  Hofmann A W,Jochum K P,Seufert M,et al.1986.Nb and Pb in oceanic basalts:new constraints on mantle evolution.Earth and Planetary Science Letters,79:33~45.
[30]  Klemd R,Schroter F C,Will T M,et al.2002.P-T evolution of glaucophane-omphacite bearing HP-LT rocks in the western Tianshan Orogen,NW China:new evidence for \'Alpine-type\' tectonics.Journal of Metamorphic Geology,20:239~254.
[31]  Peacock S M.1993.The importance of blueschist → eclogite dehydration reactions in subducting oceanic crust.Geological Society of America Bulletin,105:684~694.
[32]  Stalder R,Foley S F,Brey G P,et al.1998.Mineral-aqueous fluid partitioning of trace elements at 900~1200°C and 3.0~5.7 GPa:new experimental data for garnet,clinopyroxene,and rutile,and implications for mantle metasomatism.Geochimica et Cosmochimica Acta,62(10):1781~1801.
[33]  Wei C J,Powell R,Zhang L F.2003.Eclogites from the south Tienshan,NW China:petrological characteristic and calculated mineral equilibria in the Na2O-CaO-FeO-MgO-Al2O3-SiO2-H2O system.Journal of Metamorphic Geology,21:163~179.
[34]  Zhang L,Ellis D J,Jiang W.2002a.Ultrahigh-pressure metamorphism in western Tianshan,China:Part I.Evidence from inclusions of coesite pseudomorphs in garnet and from quartz exsolution lamellae in omphacite in eclogites.American Mineralogist,87:853~860.

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