云南个旧似长石正长岩类及其岩石成因
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摘要
云南个旧碱性岩体主要的岩石类型有碱性正长岩和似长石正长岩,其中,似长石正长岩中出现大量似长石矿物霞石、方钠石和碱性暗色矿物。本文根据矿物成分及特征,将这些似长石正长岩进一步划分为黑榴霞石方钠正长岩、霞石方钠正长岩、霞石正长岩及方钠霞石正长岩4类。岩石地球化学结果表明,4类岩石的地球化学行为整体表现出过碱质岩的特征,K2O+Na2O含量很高,为钾玄岩系列,同时表现出钾质的特点。分异指数高,呈现高度分异演化特点。稀土元素变化大,轻重稀土元素分异明显,富集轻稀土元素,亏损重稀土元素。微量元素富集大离子亲石元素Th、U及Zr、Hf等高场强元素,亏损Ba、Sr大离子亲石元素,而P和高场强元素Ta、Ti亏损,同时Cr、Co、Ni含量非常低,具有中等的负Eu异常和微弱的负Ce异常。研究表明,似长石正长岩在岩浆演化过程中表现出明显的分离结晶作用特征,且岩浆起源温度较高,约为835℃,起源较深。个旧似长石正长岩为A型岩套A1亚型,结合构造判别图解,认为其可能来自角闪石或者金云母相矿物存在的富集地幔,形成于燕山晚期伸展的构造背景,岩浆在较高温度下高度结晶分异,并在侵位过程中伴随陆壳成分的混染。
The main types of alkaline rocks in Gejiu,Yunnan are alkaline and feldspathoid syenites.The feldspathoid syenite contains many feldspathoid minerals including nepheline,sodalite and alkaline dark minerals.In this paper,we further divide the feldspathoid syenite into four categories according to its mineral composition and characteristics:melanite nepheline sodalite,nepheline sodalite,nepheline and sodalite nepheline syenites.Geochemical analysis revealed peralkaline characteristics with very high K2 O+Na2 O content.The rocks also show potassium characteristics.The high rock differentiation index(DI)indicates high degree evolutionary differentiation of magma at its origin.The rare earth element(REE)patterns show enrichment in light rare earth elements(LREE)and depletion in heavy rare earth elements(HREE).The rocks are generally enriched in high field strength elements(HFSE)Zr and Hf but depleted in Ta and Ti;they are enriched in large ion lithophile elements(LILE)Th and U but depleted in Ba and Sr,and P.They have low Cr,Co and Ni contents and moderate negative Eu and weak negative Ce anomalies.These petrographic and geochemical features are obvious indication that feldspathoid syenite underwent fractional crystallization during the magmatic evolution.The temperature of the magma origin was about 835℃ and the origin laid relatively deep.The rock subtype is A1 of the A type suites.We suggest that the Gejiu feldspathoid syenite may be the product of high fractional crystallization from enriched mantle of amphibole or phlogopite facies at high temperatures and that it was formed in the late Yanshanian extensional tectonic setting with the mixing of continental crust components.
The main types of alkaline rocks in Gejiu,Yunnan are alkaline and feldspathoid syenites.The feldspathoid syenite contains many feldspathoid minerals including nepheline,sodalite and alkaline dark minerals.In this paper,we further divide the feldspathoid syenite into four categories according to its mineral composition and characteristics:melanite nepheline sodalite,nepheline sodalite,nepheline and sodalite nepheline syenites.Geochemical analysis revealed peralkaline characteristics with very high K2 O+Na2 O content.The rocks also show potassium characteristics.The high rock differentiation index(DI)indicates high degree evolutionary differentiation of magma at its origin.The rare earth element(REE)patterns show enrichment in light rare earth elements(LREE)and depletion in heavy rare earth elements(HREE).The rocks are generally enriched in high field strength elements(HFSE)Zr and Hf but depleted in Ta and Ti;they are enriched in large ion lithophile elements(LILE)Th and U but depleted in Ba and Sr,and P.They have low Cr,Co and Ni contents and moderate negative Eu and weak negative Ce anomalies.These petrographic and geochemical features are obvious indication that feldspathoid syenite underwent fractional crystallization during the magmatic evolution.The temperature of the magma origin was about 835℃ and the origin laid relatively deep.The rock subtype is A1 of the A type suites.We suggest that the Gejiu feldspathoid syenite may be the product of high fractional crystallization from enriched mantle of amphibole or phlogopite facies at high temperatures and that it was formed in the late Yanshanian extensional tectonic setting with the mixing of continental crust components.
引文
[1]黄文龙,许继峰,陈建林,等.云南个旧杂岩体年代学与地球化学:岩石成因和幔源岩浆对锡成矿贡献[J].岩石学报,2016,32(8):2330-2346.
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[9]戴福盛.个旧锡矿区两个成岩系列的演化[J].岩石矿物学杂志,1990,9(3):224-233.
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[11]刘红英,张玉泉,夏斌.滇西两个碱性岩体Rb、Sr同位素资料的再认识[J].云南地质,2004,23(1):52-59.
[12]程彦博,毛景文,陈懋弘,等.云南个旧锡矿田碱性岩和煌斑岩LA-ICP-MS锆石U-Pb测年及其地质意义[J].中国地质,2008,35(6):1138-1149.
[13]谢应雯,张玉泉,胡国相.哀牢山-金沙江富碱侵入带地球化学与成矿专属性初步研究[J].昆明理工学院学报,1984(4):1-17.
[14]赵振华,周玲棣.我国某些富碱侵入岩的稀土元素地球化学[J].中国科学,1994,24(10):1109-1120.
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[16]段建中.金沙江-红河富碱侵入岩带岩石-矿物学及岩石化学特征[J].云南地质,2000,19(3):207-231.
[17]张颖,黄智龙,罗泰义,等.云南个旧西区贾沙辉长岩-二长岩体SIMS锆石U-Pb定年及地球化学研究[J].地球化学,2013,42(6):523-543.
[18]薛步高.个旧霞石正长岩地质特征及其开发途径探讨[J].非金属矿,1999,22(1):42-44.
[19] MIDDLEMOST E A K.Naming materials in the magma/igneous rock system[J].Earth-Science Reviews,1994,37(3/4):215-224.
[20]于炳松,赵志丹,苏尚国.岩石学[M].2版.北京:地质出版社,2012:53-57.
[21] PECCERILLO A,TAYLOR S R.Geochemistry of eocene calc-alkaline volcanic rocks from the Kastamonu area,northern Turkey[J].Contributions to Mineralogy and Petrology,1976,58(1):63-81.
[22] MIDDLEMOST E A K.A simple classification of volcanic rocks[J].Bulletin Volcanologique,1972,36(2):382-397.
[23] WRIGHT J B.A simple alkalinity ratio and its application to questions of non-orogenic genesis[J].Geological Magazine,1969,106(4):370-384.
[24] MANIAR P D,PICCOLI P M.Tectonic discrimination of granitoids[J].Geological Society of America Bulletin,1989,101(5):635-643.
[25]王梦亚.陕西省洛南长岭正长岩矿物学及地球化学研究[D].北京:中国地质大学(北京),2017:1-69.
[26] SUN S S,MCDONOUGH W F.Chemical and isotopic systematics of oceanic basalts:implications for mantle composition and processes[J].Geological Society,London,Special Publications,1989,42(1):313-345.
[27] MCDONOUGH W F,SUN S S.The composition of the Earth[J].Chemical Geology,1995,120(3/4):223-253.
[28]张遵忠,顾连兴,吴昌志,等.东天山印支早期尾亚石英正长岩:成岩作用及成岩意义[J].岩石学报,2006,22(5):1135-1149.
[29] GREEN T H.Significance of Nb/Ta as an indicator of geochemical processes in the crust-mantle system[J].Chemical Geology,1995,120(3/4):347-359.
[30] YANG J H,SUN J F,ZHANG M,et al.Petrogenesis of silica-saturated and silica-undersaturated syenites in the northern North China Craton related to post-collisional and intraplate extension[J].Chemical Geology,2012,328:149-167.
[31] BOTTINGA Y,ALLEGRE C J,THOMPSON R N.Partial melting under spreading ridges[J].Philosophical Transactions of the Royal Society of London A:Mathematical,Physical and Engineering Sciences,1978,288(1355):501-525.
[32] CALVIN F M,MCDOWELL S M,MAPES R W.Granites implication of zircon saturation temperatures and preservation of inheritance[J].Geology,2003,31(6):529-532.
[33] WATSON E B,HAEEISON T M.Zircon saturation revisited:temperature and composition effects in a variety of crustal magma types[J].Earth and Planetary Science Letters,1983,64(2):295-304.
[34] TUREKIAN K K,WEDEPOHL K H.Distribution of the elements in some major units of the Earth's crust[J].Geological Society of America Bulletin,1961,72(2):175.
[35]吴锁平,王梅英,戚开静.A型花岗岩研究现状及其评述[J].岩石矿物学杂志,2007,26(1):57-66.
[36]贾小辉,王强,唐功建.A型花岗岩的研究进展及意义[J].大地构造与成矿学,2009,33(3):465-480.
[37] EBY G N.Chemical subdivision of the A-type granitoids:petrogenesis and tectonic implications[J].Geology,1992,20(7):641-644.
[38]洪大卫,王光洸,韩宝福,等.碱性花岗岩的构造环境分类及其鉴别标志[J].中国科学:B辑,1995,25(4):418-426.
[39]刘昌实,陈小明,陈培荣,等.A型岩套的分类、判别标志和成因[J].高校地质学报,2003,9(4):418-426.
[40] BEA F,ARZAMASTSEV A,MONTERO P,et al.Anomalous alkaline rocks of Soustov,Kola:evidence of mantle-derived metasomatic fluids affecting crustal materials[J].Contributions to Mineralogy and Petrology,2001,140(5):554-566.
[41] TAYLOR S R,MCCLENNAN S M.The continental crust:its composition and evolution:an examination of the geochemical record preserved in sedimentary rocks[M].Oxford:Blackwell Scientific Publications,1985:1-312.
[42] FOLEY S F,VENTURELLI G,GREEN D H,et al.The ultrapotassic rocks:characteristics,classification,and constraints for petrogenetic models[J].Earth-Science Reviews,1987,24(2):81-134.
[43]王涛,刘燊,马润泽.山东胶南燕山期碱性正长岩的地球化学及其成因探讨[J].矿物岩石,2013,33(3):54-62.
[44]黄芳燕.海南岛侏罗纪辉长岩-正长岩套地球化学特征与构造意义[D].北京:中国地质大学(北京),2016:1-54.
[45]王中刚,于学元,赵振华,等.稀土元素地球化学[M].北京:科学出版社,1989:233-235.
[46] ZHANG H F,SUN M,ZHOU X H,et al.Geochemical constraints on the origin of Mesozoic alkaline intrusive complexes from the North China Craton and tectonic implication[J].Lithos,2005,81(1/2/3/4):297-317.
[47] WHALEN J B,CURRIE K L,CHAPPELL B W.A-type granites:geochemical characteristics discrimination and petrogenesis[J].Contributions to Mineralogy and Petrology,1987,95(4):407-419.
[48]任康绪.碱性岩研究进展述评[J].化工矿产地质,2003,25(3):151-163.
[49] BROWN G C.Calc-alkaline intrusive rocks:their diversity,evolution,and relation to volcanic arcs[M].New York:John Wiley and Sons,1982:437-464.
[2]王兴阵.个旧岩浆杂岩地质地球化学及成因研究[D].贵阳:中国科学院地球化学研究所,2006:1-70.
[3]程彦博,毛景文,谢桂青,等.与云南个旧超大型锡矿床有关的花岗岩的锆石U-Pb定年及意义[J].矿床地质,2009,28(3):297-312.
[4] CHENG Y B,MAO J W,CARL S.Petrogenesis and geodynamic implications of Gejiu igneous complex in the western Cathaysia block,South China[J].Lithos,2013,175/176:213-229.
[5] LI X L,MAO J W,CHENG Y B,et al.Petrogenesis of the Gaofengshan granite in Gejiu area,Yunnan Province:zircon U-Pb dating and geochemical constraints[J].Acta Petrologica Sinica,2012,28(1):183-198.
[6]李家和.个旧锡矿花岗岩特征及成因研究[J].云南地质,1985,4(4):327-350.
[7]虞裕如.个旧白云山碱性岩体的稀土元素特征研究[J].云南地质,1993,12(3):277-289.
[8]李志群.个旧复式侵入岩体成岩系列研究[J].云南地质,1992,11(1):15-20.
[9]戴福盛.个旧锡矿区两个成岩系列的演化[J].岩石矿物学杂志,1990,9(3):224-233.
[10]陈百友,虞裕如,江鸿飞.云南省个旧市白云山霞石正长岩矿床地质特征[J].矿床地质,2002,21(增刊1):901-905.
[11]刘红英,张玉泉,夏斌.滇西两个碱性岩体Rb、Sr同位素资料的再认识[J].云南地质,2004,23(1):52-59.
[12]程彦博,毛景文,陈懋弘,等.云南个旧锡矿田碱性岩和煌斑岩LA-ICP-MS锆石U-Pb测年及其地质意义[J].中国地质,2008,35(6):1138-1149.
[13]谢应雯,张玉泉,胡国相.哀牢山-金沙江富碱侵入带地球化学与成矿专属性初步研究[J].昆明理工学院学报,1984(4):1-17.
[14]赵振华,周玲棣.我国某些富碱侵入岩的稀土元素地球化学[J].中国科学,1994,24(10):1109-1120.
[15]周玲棣,赵振华.我国富碱侵入岩的岩石学和岩石化学特征[J].中国科学,1994,24(10):1093-1101.
[16]段建中.金沙江-红河富碱侵入岩带岩石-矿物学及岩石化学特征[J].云南地质,2000,19(3):207-231.
[17]张颖,黄智龙,罗泰义,等.云南个旧西区贾沙辉长岩-二长岩体SIMS锆石U-Pb定年及地球化学研究[J].地球化学,2013,42(6):523-543.
[18]薛步高.个旧霞石正长岩地质特征及其开发途径探讨[J].非金属矿,1999,22(1):42-44.
[19] MIDDLEMOST E A K.Naming materials in the magma/igneous rock system[J].Earth-Science Reviews,1994,37(3/4):215-224.
[20]于炳松,赵志丹,苏尚国.岩石学[M].2版.北京:地质出版社,2012:53-57.
[21] PECCERILLO A,TAYLOR S R.Geochemistry of eocene calc-alkaline volcanic rocks from the Kastamonu area,northern Turkey[J].Contributions to Mineralogy and Petrology,1976,58(1):63-81.
[22] MIDDLEMOST E A K.A simple classification of volcanic rocks[J].Bulletin Volcanologique,1972,36(2):382-397.
[23] WRIGHT J B.A simple alkalinity ratio and its application to questions of non-orogenic genesis[J].Geological Magazine,1969,106(4):370-384.
[24] MANIAR P D,PICCOLI P M.Tectonic discrimination of granitoids[J].Geological Society of America Bulletin,1989,101(5):635-643.
[25]王梦亚.陕西省洛南长岭正长岩矿物学及地球化学研究[D].北京:中国地质大学(北京),2017:1-69.
[26] SUN S S,MCDONOUGH W F.Chemical and isotopic systematics of oceanic basalts:implications for mantle composition and processes[J].Geological Society,London,Special Publications,1989,42(1):313-345.
[27] MCDONOUGH W F,SUN S S.The composition of the Earth[J].Chemical Geology,1995,120(3/4):223-253.
[28]张遵忠,顾连兴,吴昌志,等.东天山印支早期尾亚石英正长岩:成岩作用及成岩意义[J].岩石学报,2006,22(5):1135-1149.
[29] GREEN T H.Significance of Nb/Ta as an indicator of geochemical processes in the crust-mantle system[J].Chemical Geology,1995,120(3/4):347-359.
[30] YANG J H,SUN J F,ZHANG M,et al.Petrogenesis of silica-saturated and silica-undersaturated syenites in the northern North China Craton related to post-collisional and intraplate extension[J].Chemical Geology,2012,328:149-167.
[31] BOTTINGA Y,ALLEGRE C J,THOMPSON R N.Partial melting under spreading ridges[J].Philosophical Transactions of the Royal Society of London A:Mathematical,Physical and Engineering Sciences,1978,288(1355):501-525.
[32] CALVIN F M,MCDOWELL S M,MAPES R W.Granites implication of zircon saturation temperatures and preservation of inheritance[J].Geology,2003,31(6):529-532.
[33] WATSON E B,HAEEISON T M.Zircon saturation revisited:temperature and composition effects in a variety of crustal magma types[J].Earth and Planetary Science Letters,1983,64(2):295-304.
[34] TUREKIAN K K,WEDEPOHL K H.Distribution of the elements in some major units of the Earth's crust[J].Geological Society of America Bulletin,1961,72(2):175.
[35]吴锁平,王梅英,戚开静.A型花岗岩研究现状及其评述[J].岩石矿物学杂志,2007,26(1):57-66.
[36]贾小辉,王强,唐功建.A型花岗岩的研究进展及意义[J].大地构造与成矿学,2009,33(3):465-480.
[37] EBY G N.Chemical subdivision of the A-type granitoids:petrogenesis and tectonic implications[J].Geology,1992,20(7):641-644.
[38]洪大卫,王光洸,韩宝福,等.碱性花岗岩的构造环境分类及其鉴别标志[J].中国科学:B辑,1995,25(4):418-426.
[39]刘昌实,陈小明,陈培荣,等.A型岩套的分类、判别标志和成因[J].高校地质学报,2003,9(4):418-426.
[40] BEA F,ARZAMASTSEV A,MONTERO P,et al.Anomalous alkaline rocks of Soustov,Kola:evidence of mantle-derived metasomatic fluids affecting crustal materials[J].Contributions to Mineralogy and Petrology,2001,140(5):554-566.
[41] TAYLOR S R,MCCLENNAN S M.The continental crust:its composition and evolution:an examination of the geochemical record preserved in sedimentary rocks[M].Oxford:Blackwell Scientific Publications,1985:1-312.
[42] FOLEY S F,VENTURELLI G,GREEN D H,et al.The ultrapotassic rocks:characteristics,classification,and constraints for petrogenetic models[J].Earth-Science Reviews,1987,24(2):81-134.
[43]王涛,刘燊,马润泽.山东胶南燕山期碱性正长岩的地球化学及其成因探讨[J].矿物岩石,2013,33(3):54-62.
[44]黄芳燕.海南岛侏罗纪辉长岩-正长岩套地球化学特征与构造意义[D].北京:中国地质大学(北京),2016:1-54.
[45]王中刚,于学元,赵振华,等.稀土元素地球化学[M].北京:科学出版社,1989:233-235.
[46] ZHANG H F,SUN M,ZHOU X H,et al.Geochemical constraints on the origin of Mesozoic alkaline intrusive complexes from the North China Craton and tectonic implication[J].Lithos,2005,81(1/2/3/4):297-317.
[47] WHALEN J B,CURRIE K L,CHAPPELL B W.A-type granites:geochemical characteristics discrimination and petrogenesis[J].Contributions to Mineralogy and Petrology,1987,95(4):407-419.
[48]任康绪.碱性岩研究进展述评[J].化工矿产地质,2003,25(3):151-163.
[49] BROWN G C.Calc-alkaline intrusive rocks:their diversity,evolution,and relation to volcanic arcs[M].New York:John Wiley and Sons,1982:437-464.