云南中甸地区两个斑岩铜矿容矿斑岩的地球化学特征——以雪鸡坪和普朗斑岩铜矿床为例
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摘要
位于义敦岛弧南端的中甸岛弧已成为我国又一重要的斑岩铜矿产地,其中雪鸡坪中型斑岩铜矿床产于西斑岩带,普朗超大型斑岩铜矿床产于东斑岩带。详细对比研究了这两个斑岩铜矿床矿床地质,含矿斑岩的岩石化学、地球化学以及年代学等特征,认为:①两者的元素组成非常相似,如稀土配分形式均为轻稀土元素富集型,亏损重稀土元素和Y,富集Sr、K、Rb、Ba、Th等大离子亲石元素,亏损Nb、Ta、Zr、Hf、Ti等高场强元素,显示了埃达克岩的地球化学特征,表明它们可能是俯冲的甘孜—理塘洋壳部分熔融的产物,并受到地壳物质的混染;②中甸岛弧的结构及时空演化保持了义敦岛弧的共性,发育完整的沟-弧-盆体系,其中东斑岩带属于外弧,而西斑岩带属于内弧,中斑岩带及零星分布的属都蛇绿混杂岩产于弧间盆地。
Recent studies suggest that the Zhongdian Arc,south of the Yidun Island Arc,has become one of our country's important producing areas of porphyry copper ores.One of them,the Xuejiping medium-scale porphyry copper deposit,lies in western porphyry belt;and in eastern porphyry belt the Pulang superlarge-scale porphyry copper deposit lies.Detailed comparison and study were made in this paper.The geological characteristics,petro-chemistry,geochemistry and chronology of the two porphyry copper depositsr are dealt with,and the understandings are presented below:(1)The two deposits have very similar elemental compositions,e.g.both are enriched in LREE,depleted in HREE and Y,enriched in LIL elements such as Sr,K,Rb,Ba,Th,etc.,depleted in HFS elements such as Nb,Ta,Zr,Hf,Ti,etc.All this indicates that the two deposits are the products of partial melting at Ganzi-Litang and have been contaminated by crustal materials.(2)As the structural and spatial and temporal evolution of the Zhongdian Arc maintain most of the characteristics of the Yidun Island Arc,it has developed as an integrated T-A-BA system.In the system the eastern porphyry belt is situated on the outer arc,the western porphyry belt on the inner arc,and the middle porphyry belt and Shundu ophiolitic mélange with in the interarc basin.
Recent studies suggest that the Zhongdian Arc,south of the Yidun Island Arc,has become one of our country's important producing areas of porphyry copper ores.One of them,the Xuejiping medium-scale porphyry copper deposit,lies in western porphyry belt;and in eastern porphyry belt the Pulang superlarge-scale porphyry copper deposit lies.Detailed comparison and study were made in this paper.The geological characteristics,petro-chemistry,geochemistry and chronology of the two porphyry copper depositsr are dealt with,and the understandings are presented below:(1)The two deposits have very similar elemental compositions,e.g.both are enriched in LREE,depleted in HREE and Y,enriched in LIL elements such as Sr,K,Rb,Ba,Th,etc.,depleted in HFS elements such as Nb,Ta,Zr,Hf,Ti,etc.All this indicates that the two deposits are the products of partial melting at Ganzi-Litang and have been contaminated by crustal materials.(2)As the structural and spatial and temporal evolution of the Zhongdian Arc maintain most of the characteristics of the Yidun Island Arc,it has developed as an integrated T-A-BA system.In the system the eastern porphyry belt is situated on the outer arc,the western porphyry belt on the inner arc,and the middle porphyry belt and Shundu ophiolitic mélange with in the interarc basin.
引文
[1]杨岳清,侯增谦,黄典豪,等.中甸弧碰撞造山作用与岩浆成矿系统[J].地球学报,2002,23(1):17-24.
[2]曾普胜,莫宣学,喻学惠,等.滇西北中甸地区中酸性斑岩及其含矿性初步研究[J].地球学报,1999,20(增刊):359-336.
[3]曾普胜,莫宣学,喻学惠,等.滇西北中甸斑岩及斑岩铜矿[J].矿床地质,2003,20(4):393-400.
[4]曾普胜,王海平,莫宣学,等.中甸岛弧带构造格架及斑岩铜矿前景[J].地球学报,2004,25(5):535-540.
[5]曾普胜,李文昌,王海平,等.云南普朗印支期超大型斑岩铜矿床:岩石学及年代学特征[J].岩石学报,2006,22(4):989-1000.
[6]Hou Z-Q,Ma H-W,Za W-K,et al.The Himalayan Yulong porphyry copper belt:Product of strike-slipfaultingin eatern Tibet[J].Economic Geolo-gy,2003,98:125-145.
[7]林清茶,夏斌,张玉泉.云南中甸地区雪鸡坪同碰撞石英闪长玢岩锆石SHRIMP U-Pb定年及其意义[J].地质通报,2006,25(1-2):133-135.
[8]候增谦.三江地区义敦岛弧构造-岩浆演化特征[A].地质矿产部.青藏高原地质文集[C].北京:地质出版社,1991,21:163-165.
[9]钟惜时.雪鸡坪斑岩铜矿地质特征及对成矿因素的初步认识[J].云南地质,1982,1(2):134-146.
[10]范玉华,李文昌.南普朗斑岩铜矿床地质特征[J].中国地质,2006,33(2):352-361.
[11]吕伯西,王增,张能德,等.三江地区花岗岩类及其成矿专属性[M].北京:地质出版社,1993:32-47.
[12]张玉学,陈文一,王成元.云南雪鸡坪斑岩铜矿床地球化学特征及成因研究[M].中国科学院地球化学研究所矿床地球化学开放实验室年报,1990:105-115.
[13]Irvine TN,Baragar WR A.Aguide tothe chemical classification of the common volcanic rocks[J].Canad Earth Sci,1971,8:523-548.
[14]Muller D,Heithersag PS,Groves DI.The shoshonite porphyry Cu-Auassociationinthe Gronumbla district,N.S.W.,Australia[J].MineralPetrol,1993,51:299-321.
[15]Boynton WV.Geochemistry of the rare earth elements:meteorite studies[A].Henderson P.Rare Earth Elements Geochemistry[M].Amsterdam:Elsevier,1984:63-114.
[16]Pearce J A,Harris NB W,Tindle AG.Trace element discrimination diagramsforthetectonic interpretation of granitic rocks[J].Petrol,1984,25:956-983.
[17]Martin H.Effect of steeper Archaean geothermal gradient on geochemistry of subduction-zone magmas[J].Geology,1986,14:753-756.
[18]Martin H.Adakitic magmas:modern analogues of Archaean granitoids[J].Lithos,1999,46:411-429.
[19]Defant MJ,Drummond MS.Derivation of some modern arc magmas by melting of youngsubductionlithosphere[J].Nature,1990,347:662-665.
[20]Atherton MP,Petford N.Generation of sodium-rich magmas fromnewly underplated basaltic crust[J].Nature,1993,362:144-146.
[21]云南省地质矿产局.云南区域地质志[M].北京:地质出版社,1990.
[22]Thi啨blemont D,Stein G,Lescuyer J L.Gisements啨pithermaux et porphyriques:la connexion adakite[J].C R Acad Sci Paris Earth Planet Sci,1997,325:103-109.
[23]Sajona F G,Maury RC.Association of adakites withgold and copper mineralisationin Philippines[J].C RAcadSci Paris Earth Planet Sci,1998,326(1):27-34.
[24]Oyarz挷n R,M偄rquez A,Lillo J,et al.Giant versus small porphyry copper deposits of Cenozoic age in northern Chile:adakitic versus normal calc-al-kaline magmatism[J].Mineralium Deposita,2001,36:794-798.
[25]Munhall J E.Roastingthe mantle:slab melting andthe genesis of major Au and Au-rich Cu deposits[J].Geology,2002,30:915-918.
[26]张旗,王焰,钱青,等.中国东北燕山期埃达克岩的特征及其构造-成矿意义[J].岩石学报,2001,17(2):236-244.
[27]侯增谦,莫宣学,高永丰,等.埃达克岩:斑岩铜矿的一种可能的含矿母岩-以西藏和智利斑岩铜为例[J].矿床地质,2003,22(1):1-12.
[28]赵振华,王强,熊小林,等.新疆北部的两类埃达克岩[J].岩石学报,2006,22(5):1249-1265.
[29]王元龙,张旗,王强,等.埃达克质岩与Cu-Au成矿作用关系的初步探讨[J].岩石学报,2003,19(3):543-550.
[30]王强,许继锋,赵振华.一种新的火成岩-埃达克岩的研究综述[J].地球科学进展,2001,16(2):201-208.
[31]秦克章,王之田.内蒙古乌奴格吐山铜-钼矿床稀土元素的行为及意义[J].地质学报,1993,67(4):323-335.
[32]孟祥金,侯增谦,高永丰,等.碰撞造山型斑岩铜矿蚀变分带模式—以西藏冈底斯斑岩铜矿带为例[J].地学前缘,2004,11(3):201-212.
[33]Robert P R,肖龙,Nobu S.Experimental constraints onthe origin of potassium-rich adakites ineastern China[J].岩石学报,2002,18(3):293-302.
[34]侯增谦、杨岳清、曲晓明,等.三江地区义敦岛弧造山带演化和成矿系统[J].地质学报,2004,78(1):109-118.
[35]侯增谦,杨岳清,王海平,等.三江义敦岛弧碰撞造山过程与成矿系统[M].北京:地质出版社,2003,l-345.
[36]侯增谦,侯立纬,叶庆同,等.三江地区义敦岛弧构造一岩浆演化与火山成因块状硫化物矿床[M].北京:地震出版社,1995.
[37]Yogodzinski G M,Kay R W,Bolynets ON,et al.Magnesian andesite inthe western Aleutian Komandorskyregion:Implicationsfor slab melting andprocesses inthe mantle wedge[J].Geol Soc AmBull,1995,107:505-519.
[38]Yogodzinski G M,Lees J M,Churikova TG,et al.Geochemical evidence for the melting of subducting oceanic lithosphere at plates edges[J].Na-ture,2001,409:500-504.
[39]Gutscher MA,Maury F,Eissen J P,et al.Can slab melting be caused byflat subduction?[J].Geology,2000,28:535-538.
[2]曾普胜,莫宣学,喻学惠,等.滇西北中甸地区中酸性斑岩及其含矿性初步研究[J].地球学报,1999,20(增刊):359-336.
[3]曾普胜,莫宣学,喻学惠,等.滇西北中甸斑岩及斑岩铜矿[J].矿床地质,2003,20(4):393-400.
[4]曾普胜,王海平,莫宣学,等.中甸岛弧带构造格架及斑岩铜矿前景[J].地球学报,2004,25(5):535-540.
[5]曾普胜,李文昌,王海平,等.云南普朗印支期超大型斑岩铜矿床:岩石学及年代学特征[J].岩石学报,2006,22(4):989-1000.
[6]Hou Z-Q,Ma H-W,Za W-K,et al.The Himalayan Yulong porphyry copper belt:Product of strike-slipfaultingin eatern Tibet[J].Economic Geolo-gy,2003,98:125-145.
[7]林清茶,夏斌,张玉泉.云南中甸地区雪鸡坪同碰撞石英闪长玢岩锆石SHRIMP U-Pb定年及其意义[J].地质通报,2006,25(1-2):133-135.
[8]候增谦.三江地区义敦岛弧构造-岩浆演化特征[A].地质矿产部.青藏高原地质文集[C].北京:地质出版社,1991,21:163-165.
[9]钟惜时.雪鸡坪斑岩铜矿地质特征及对成矿因素的初步认识[J].云南地质,1982,1(2):134-146.
[10]范玉华,李文昌.南普朗斑岩铜矿床地质特征[J].中国地质,2006,33(2):352-361.
[11]吕伯西,王增,张能德,等.三江地区花岗岩类及其成矿专属性[M].北京:地质出版社,1993:32-47.
[12]张玉学,陈文一,王成元.云南雪鸡坪斑岩铜矿床地球化学特征及成因研究[M].中国科学院地球化学研究所矿床地球化学开放实验室年报,1990:105-115.
[13]Irvine TN,Baragar WR A.Aguide tothe chemical classification of the common volcanic rocks[J].Canad Earth Sci,1971,8:523-548.
[14]Muller D,Heithersag PS,Groves DI.The shoshonite porphyry Cu-Auassociationinthe Gronumbla district,N.S.W.,Australia[J].MineralPetrol,1993,51:299-321.
[15]Boynton WV.Geochemistry of the rare earth elements:meteorite studies[A].Henderson P.Rare Earth Elements Geochemistry[M].Amsterdam:Elsevier,1984:63-114.
[16]Pearce J A,Harris NB W,Tindle AG.Trace element discrimination diagramsforthetectonic interpretation of granitic rocks[J].Petrol,1984,25:956-983.
[17]Martin H.Effect of steeper Archaean geothermal gradient on geochemistry of subduction-zone magmas[J].Geology,1986,14:753-756.
[18]Martin H.Adakitic magmas:modern analogues of Archaean granitoids[J].Lithos,1999,46:411-429.
[19]Defant MJ,Drummond MS.Derivation of some modern arc magmas by melting of youngsubductionlithosphere[J].Nature,1990,347:662-665.
[20]Atherton MP,Petford N.Generation of sodium-rich magmas fromnewly underplated basaltic crust[J].Nature,1993,362:144-146.
[21]云南省地质矿产局.云南区域地质志[M].北京:地质出版社,1990.
[22]Thi啨blemont D,Stein G,Lescuyer J L.Gisements啨pithermaux et porphyriques:la connexion adakite[J].C R Acad Sci Paris Earth Planet Sci,1997,325:103-109.
[23]Sajona F G,Maury RC.Association of adakites withgold and copper mineralisationin Philippines[J].C RAcadSci Paris Earth Planet Sci,1998,326(1):27-34.
[24]Oyarz挷n R,M偄rquez A,Lillo J,et al.Giant versus small porphyry copper deposits of Cenozoic age in northern Chile:adakitic versus normal calc-al-kaline magmatism[J].Mineralium Deposita,2001,36:794-798.
[25]Munhall J E.Roastingthe mantle:slab melting andthe genesis of major Au and Au-rich Cu deposits[J].Geology,2002,30:915-918.
[26]张旗,王焰,钱青,等.中国东北燕山期埃达克岩的特征及其构造-成矿意义[J].岩石学报,2001,17(2):236-244.
[27]侯增谦,莫宣学,高永丰,等.埃达克岩:斑岩铜矿的一种可能的含矿母岩-以西藏和智利斑岩铜为例[J].矿床地质,2003,22(1):1-12.
[28]赵振华,王强,熊小林,等.新疆北部的两类埃达克岩[J].岩石学报,2006,22(5):1249-1265.
[29]王元龙,张旗,王强,等.埃达克质岩与Cu-Au成矿作用关系的初步探讨[J].岩石学报,2003,19(3):543-550.
[30]王强,许继锋,赵振华.一种新的火成岩-埃达克岩的研究综述[J].地球科学进展,2001,16(2):201-208.
[31]秦克章,王之田.内蒙古乌奴格吐山铜-钼矿床稀土元素的行为及意义[J].地质学报,1993,67(4):323-335.
[32]孟祥金,侯增谦,高永丰,等.碰撞造山型斑岩铜矿蚀变分带模式—以西藏冈底斯斑岩铜矿带为例[J].地学前缘,2004,11(3):201-212.
[33]Robert P R,肖龙,Nobu S.Experimental constraints onthe origin of potassium-rich adakites ineastern China[J].岩石学报,2002,18(3):293-302.
[34]侯增谦、杨岳清、曲晓明,等.三江地区义敦岛弧造山带演化和成矿系统[J].地质学报,2004,78(1):109-118.
[35]侯增谦,杨岳清,王海平,等.三江义敦岛弧碰撞造山过程与成矿系统[M].北京:地质出版社,2003,l-345.
[36]侯增谦,侯立纬,叶庆同,等.三江地区义敦岛弧构造一岩浆演化与火山成因块状硫化物矿床[M].北京:地震出版社,1995.
[37]Yogodzinski G M,Kay R W,Bolynets ON,et al.Magnesian andesite inthe western Aleutian Komandorskyregion:Implicationsfor slab melting andprocesses inthe mantle wedge[J].Geol Soc AmBull,1995,107:505-519.
[38]Yogodzinski G M,Lees J M,Churikova TG,et al.Geochemical evidence for the melting of subducting oceanic lithosphere at plates edges[J].Na-ture,2001,409:500-504.
[39]Gutscher MA,Maury F,Eissen J P,et al.Can slab melting be caused byflat subduction?[J].Geology,2000,28:535-538.
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