杭带锡田合江口锡钨矿床流体包裹体和稳定同位素特征
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摘要
合江口锡钨多金属矿为钦杭缝合带上锡田矿田中的岩浆热液型矿床。为探讨矿床的成矿流体性质、演化及成因机制,文章分别研究了3个成矿期中流体包裹体的特征,并重点对第Ⅱ期的流体特征进行了分阶段剖析。发现第Ⅰ期为L+V型包裹体,成矿流体为中高温、中盐度H_2O-CO_2-Na Cl体系,流体不混溶作用不明显;第Ⅱ期有L+V、Cl、Cl+Cv、Aq+Cl+Cv和S型几类包裹体,初始成矿流体为高温、中盐度的H_2S-N_2-CO_2-H_2O-Na Cl体系,本期不仅新发现了大量的N_2包裹体,还见到了萤石子矿物,同时检出了大量的CO_2、H_2S、CH_4、N_2、CO、F、Cl等挥发分,挥发分对矿质的析出、溶解和搬运起了重要作用,温度-盐度的降低、挥发分逃逸、流体不混溶作用、还原至氧化环境的改变、大气水的参与是导致矿质沉淀的重要机制,本期的成矿深度约为4. 5 km,N_2的检出为幔源流体参与成矿提供了证据。第Ⅲ期主要为L+V型包裹体,流体为高温、中—高盐度的H_2O-NaCl体系。稳定同位素研究表明第Ⅰ期流体以壳源为主,第Ⅱ期为壳幔混合源,初始成矿流体主要源自岩浆水,后期有大气水混入。
The Hejiangkou Sn-W-polymetallic deposit is a magmatic-hydrothermal mineral deposit located in the Xitian orefield within the Qinzhou-Hangzhou structure. In order to understand the nature of ore-forming fluids and the genesis and evolution of the deposit,in this study,we investigated fluid inclusions formed in three different ore-forming periods. The characteristics of the fluid of Stage II are the focus of this study and were analyzed in stages. The fluid inclusions of Period I are predominantly L+V inclusions and the ore-forming fluid in this period is characterized by a moderate-temperature,moderate-salinity H_2 O-CO_2-Na Cl system. There was no obvious fluid immiscibility during Period I. The fluid inclusions of Period II can be divided into L+V,Cl,Cl+Cv,Aq+Cl+Cv,and S inclusions. The initial ore-forming fluid was a high-temperature,moderate-salinity H_2 S-N_2-CO_2-H_2 O-Na Cl system. Not only abundant N_2-bearing inclusions but also fluid inclusions containing fluorite daughter minerals occurred during this period. The presence of abundant volatiles such as CO_2,H_2 S,CH_4,N_2,CO,F,and Cl may imply that volatiles played an important role in precipitation,dissolution and transport of ore-forming materials. Moreover,decrease in temperature and salinity,escape of volatiles,fluid immiscibility,change in redox condition,and participation of meteoric water are important mechanisms for ore precipitation. The depth of mineralization of Period II is roughly 4.5 km. The presence of N_2 indicates that the mantle-derived fluids participated in the ore-forming process. The fluid inclusions of Period III are predominantly L+V inclusions and the ore-forming fluid was represented by a high-temperature,moderate to high salinity H_2 O-Na Cl system. Stable isotopic analysis reveals that the fluid of Period I was dominated by crust-derived fluid and that the fluid of Period II was formed through mixing between crust and mantle-derived fluids. In addition,the initial fluid of Period II was dominated by magmatic water and latterly meteoric water was added into the ore-forming fluid.
The Hejiangkou Sn-W-polymetallic deposit is a magmatic-hydrothermal mineral deposit located in the Xitian orefield within the Qinzhou-Hangzhou structure. In order to understand the nature of ore-forming fluids and the genesis and evolution of the deposit,in this study,we investigated fluid inclusions formed in three different ore-forming periods. The characteristics of the fluid of Stage II are the focus of this study and were analyzed in stages. The fluid inclusions of Period I are predominantly L+V inclusions and the ore-forming fluid in this period is characterized by a moderate-temperature,moderate-salinity H_2 O-CO_2-Na Cl system. There was no obvious fluid immiscibility during Period I. The fluid inclusions of Period II can be divided into L+V,Cl,Cl+Cv,Aq+Cl+Cv,and S inclusions. The initial ore-forming fluid was a high-temperature,moderate-salinity H_2 S-N_2-CO_2-H_2 O-Na Cl system. Not only abundant N_2-bearing inclusions but also fluid inclusions containing fluorite daughter minerals occurred during this period. The presence of abundant volatiles such as CO_2,H_2 S,CH_4,N_2,CO,F,and Cl may imply that volatiles played an important role in precipitation,dissolution and transport of ore-forming materials. Moreover,decrease in temperature and salinity,escape of volatiles,fluid immiscibility,change in redox condition,and participation of meteoric water are important mechanisms for ore precipitation. The depth of mineralization of Period II is roughly 4.5 km. The presence of N_2 indicates that the mantle-derived fluids participated in the ore-forming process. The fluid inclusions of Period III are predominantly L+V inclusions and the ore-forming fluid was represented by a high-temperature,moderate to high salinity H_2 O-Na Cl system. Stable isotopic analysis reveals that the fluid of Period I was dominated by crust-derived fluid and that the fluid of Period II was formed through mixing between crust and mantle-derived fluids. In addition,the initial fluid of Period II was dominated by magmatic water and latterly meteoric water was added into the ore-forming fluid.
引文
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Robinson B W and Kusakabe M.1975.Quantitative preparation of sulfur for34S/32S analyses from sulfides by combustion with cuprous oxide[J].Anal.Chem.,47:1179.
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Williams J A,Heinrich C A.2005.Vapor Transport of Metals and the formation of magmatic-hydrothermal ofre deposit[J].Econ.Geol.100:1287-1312.
蔡明海,余存林,王显彬,刘虎,郭腾飞,彭振安.2013.湘南荷花坪锡多金属矿床流体包裹体研究[J].地球学报,24(6):654-664.
蔡新华,贾宝华.2006.湖南锡田锡矿的发现及找矿潜力分析[J].中国地质,33(5):1100-1108.
邓湘伟,戴雪灵,刘广东,等.2012.钦-杭缝合带锡田合江口SP花岗岩地质地球化学特征及其对比研究[J].矿物岩石,32(02):45-55.
邓湘伟,刘继顺,戴雪灵.2015.湘东锡田合江口钨锡多金属矿床地质特征及辉钼矿Re-Os同位素年龄-兼论锡田矿田多期成矿事件[J].中国有色金属学报,25(10):2883-2898.
杜玉雕,余心起,刘家军,等.2011.皖南东源钨钼矿成矿流体特征和成矿物质来源[J].中国地质,38(5):1334-1346.
付建明,程顺波,卢友月.2012.湖南锡田云英岩-石英脉型钨锡矿的形成时代及其赋矿花岗岩锆石SHRIMP U-Pb定年[J].地质与勘探,48(2):313-341.
付建明,马丽艳,程顺波,等.2013.南岭地区锡(钨)矿成矿规律及找矿[J].高校地质学报,19(2):202-212.
付建明,伍式崇,徐德明,马丽艳,程顺波,陈希清.2009.湘东锡田钨锡多金属矿区成岩成矿时代的再厘定[J].华南地质与矿产,3:1-7.
高永宝,李文渊,张照伟.2011.祁漫塔格白干湖-戛勒赛钨锡矿带石英脉型矿石流体包裹体及氢氧同位素研究[J].岩石学报,27(06):1829-1839.
郭春丽,陈振宇,楼法生,许以明.2014.南岭与钨锡矿床有关晚侏罗世花岗岩的成矿专属性研究[J].大地构造与成矿学,38(02):301-311.
刘国庆,伍式崇,杜安道,付建明,杨晓君,汤质华,魏君奇.2008.湘东锡田钨锡矿区成岩成矿时代研究[J].大地构造与成矿学,32(1):63-71.
刘悟辉,徐文炘,戴塔根,李蘅.2006.湖南柿竹园钨锡多金属矿田野鸡尾矿床同位素地球化学研究[J].岩石学报,22(10):2517-2524.
卢焕章,范宏瑞,倪培,欧光习,沈昆,张文淮.2004.流体包裹体[M].北京:科学出版社,1-444.
马丽艳,付建明,伍式崇,徐德明,杨晓君.2008.湘东锡田垄上多金属矿床40Ar/39Ar同位素定年研究[J].中国地质,35(4):706-715.
马铁球,柏道远,邝军,王先辉.2005.湘东南茶陵地区锡田岩体锆石SHRIMP定年及其地质意义[J].地质通报,24(5):415-421.
倪永进,单业华,伍式崇,聂冠军,张小琼,朱浩峰,梁新权.2014.湘东邓阜仙-锡田印支期花岗岩体的侵位机制[J].大地构造与成矿学,140(1):82-93.
宋生琼,胡瑞忠,毕献武,魏文凤,石少华.2011.赣南崇义淘锡坑钨矿床氢、氧、硫同位素地球化学研究[J].矿床地质,30(1):1-10.
王旭东,倪培,蒋少涌,黄健宝,孙立强.2008.赣南漂塘钨矿流体包裹体研究[J].岩石学报,24(9):2163-2170.
王旭东,倪培,张伯声,王天刚.2010.江西盘古山石英脉型钨矿床流体包裹体研究[J].岩石矿物学杂志,29(5):539-550.
魏文凤,胡瑞忠,彭建堂,毕献武,宋生琼,石少华.2011.赣南西华山钨矿床的流体混合作用:基于H、O同位素模拟分析[J].地球化学,40(1):45-55.
吴自成,刘继顺,舒国文,王伟,马慧英.2010.南岭燕山期构造一岩浆热事件与锡田锡钨成矿[J].地质找矿论丛,25(3):201-205.
伍式崇,龙自强,徐辉煌,周云,蒋英,潘传楚.2012.湖南锡田锡钨多金属矿床成矿构造特征及其找矿意义[J].大地构造与成矿学,36(02):217-226.
徐辉煌,伍式崇,余阳春,谢友良,龙伟平.2006.湖南锡田地区矽卡岩型钨锡矿床地质特征及控矿因素[J].华南地质与矿产,2:37-42.
杨明桂,黄水保,楼法生,唐维新,毛素斌.2009.中国东南陆区岩石圈结构与大规模成矿作用[J].中国地质,36(3):528-543.
杨晓君,伍式崇,付建明,黄惠兰,常海亮,刘云华.2007.湘东锡田垄上锡多金属矿床流体包裹体研究[J].矿床地质,26(5):5011-5022.
张理刚.1985.莲花山斑岩型钨矿床的氢、氧、硫、碳和铅同位素地球化学[J].矿床地质,1:54-63.
张文兰.2004.赣南大吉山和漂塘花岗岩特征及成矿作用研究[D].南京大学:博士学位论文,75-80.
周云,梁新权,梁细荣,伍式崇,蒋英,温淑女,蔡永丰.2013.湖南锡田含W-Sn A型花岗岩年代学与地球化学特征[J].大地构造与成矿学,37(3):511-529.
Burnham C W.1979.Magmas and hydrothermal fluids.In:Barnes HL(ed.)Geochemistry of Hydrothermal Ore Deposits[R].New York:Honhn Wiley and Sons Inc.76-136.
Heinrich C A.1989.The chemistry of hydrothermal tin(-tungsten)ore deposition[J].Econ.Geol.,85:457-481.
Robinson B W and Kusakabe M.1975.Quantitative preparation of sulfur for34S/32S analyses from sulfides by combustion with cuprous oxide[J].Anal.Chem.,47:1179.
Roedder E.1992.Fliud in clusion evidence for in miscibility in magmatic differentiation[J].geochim cosshin Acta,(56)5-20.
Taylor H P.1979.Oxygen and hydrogen isotope relationships[C]//In:Barnes H.d.Geochemistry of hydrothermal ore deposits.2nd.New York:wiley.236-277.
Webster J D,Mandeville C W.2004.Fluid immiscibility in volcanic environments[J].Reviews in Mineralogy and Geochemistry.65(01)313-362.
Williams J A,Heinrich C A.2005.Vapor Transport of Metals and the formation of magmatic-hydrothermal ofre deposit[J].Econ.Geol.100:1287-1312.
蔡明海,余存林,王显彬,刘虎,郭腾飞,彭振安.2013.湘南荷花坪锡多金属矿床流体包裹体研究[J].地球学报,24(6):654-664.
蔡新华,贾宝华.2006.湖南锡田锡矿的发现及找矿潜力分析[J].中国地质,33(5):1100-1108.
邓湘伟,戴雪灵,刘广东,等.2012.钦-杭缝合带锡田合江口SP花岗岩地质地球化学特征及其对比研究[J].矿物岩石,32(02):45-55.
邓湘伟,刘继顺,戴雪灵.2015.湘东锡田合江口钨锡多金属矿床地质特征及辉钼矿Re-Os同位素年龄-兼论锡田矿田多期成矿事件[J].中国有色金属学报,25(10):2883-2898.
杜玉雕,余心起,刘家军,等.2011.皖南东源钨钼矿成矿流体特征和成矿物质来源[J].中国地质,38(5):1334-1346.
付建明,程顺波,卢友月.2012.湖南锡田云英岩-石英脉型钨锡矿的形成时代及其赋矿花岗岩锆石SHRIMP U-Pb定年[J].地质与勘探,48(2):313-341.
付建明,马丽艳,程顺波,等.2013.南岭地区锡(钨)矿成矿规律及找矿[J].高校地质学报,19(2):202-212.
付建明,伍式崇,徐德明,马丽艳,程顺波,陈希清.2009.湘东锡田钨锡多金属矿区成岩成矿时代的再厘定[J].华南地质与矿产,3:1-7.
高永宝,李文渊,张照伟.2011.祁漫塔格白干湖-戛勒赛钨锡矿带石英脉型矿石流体包裹体及氢氧同位素研究[J].岩石学报,27(06):1829-1839.
郭春丽,陈振宇,楼法生,许以明.2014.南岭与钨锡矿床有关晚侏罗世花岗岩的成矿专属性研究[J].大地构造与成矿学,38(02):301-311.
刘国庆,伍式崇,杜安道,付建明,杨晓君,汤质华,魏君奇.2008.湘东锡田钨锡矿区成岩成矿时代研究[J].大地构造与成矿学,32(1):63-71.
刘悟辉,徐文炘,戴塔根,李蘅.2006.湖南柿竹园钨锡多金属矿田野鸡尾矿床同位素地球化学研究[J].岩石学报,22(10):2517-2524.
卢焕章,范宏瑞,倪培,欧光习,沈昆,张文淮.2004.流体包裹体[M].北京:科学出版社,1-444.
马丽艳,付建明,伍式崇,徐德明,杨晓君.2008.湘东锡田垄上多金属矿床40Ar/39Ar同位素定年研究[J].中国地质,35(4):706-715.
马铁球,柏道远,邝军,王先辉.2005.湘东南茶陵地区锡田岩体锆石SHRIMP定年及其地质意义[J].地质通报,24(5):415-421.
倪永进,单业华,伍式崇,聂冠军,张小琼,朱浩峰,梁新权.2014.湘东邓阜仙-锡田印支期花岗岩体的侵位机制[J].大地构造与成矿学,140(1):82-93.
宋生琼,胡瑞忠,毕献武,魏文凤,石少华.2011.赣南崇义淘锡坑钨矿床氢、氧、硫同位素地球化学研究[J].矿床地质,30(1):1-10.
王旭东,倪培,蒋少涌,黄健宝,孙立强.2008.赣南漂塘钨矿流体包裹体研究[J].岩石学报,24(9):2163-2170.
王旭东,倪培,张伯声,王天刚.2010.江西盘古山石英脉型钨矿床流体包裹体研究[J].岩石矿物学杂志,29(5):539-550.
魏文凤,胡瑞忠,彭建堂,毕献武,宋生琼,石少华.2011.赣南西华山钨矿床的流体混合作用:基于H、O同位素模拟分析[J].地球化学,40(1):45-55.
吴自成,刘继顺,舒国文,王伟,马慧英.2010.南岭燕山期构造一岩浆热事件与锡田锡钨成矿[J].地质找矿论丛,25(3):201-205.
伍式崇,龙自强,徐辉煌,周云,蒋英,潘传楚.2012.湖南锡田锡钨多金属矿床成矿构造特征及其找矿意义[J].大地构造与成矿学,36(02):217-226.
徐辉煌,伍式崇,余阳春,谢友良,龙伟平.2006.湖南锡田地区矽卡岩型钨锡矿床地质特征及控矿因素[J].华南地质与矿产,2:37-42.
杨明桂,黄水保,楼法生,唐维新,毛素斌.2009.中国东南陆区岩石圈结构与大规模成矿作用[J].中国地质,36(3):528-543.
杨晓君,伍式崇,付建明,黄惠兰,常海亮,刘云华.2007.湘东锡田垄上锡多金属矿床流体包裹体研究[J].矿床地质,26(5):5011-5022.
张理刚.1985.莲花山斑岩型钨矿床的氢、氧、硫、碳和铅同位素地球化学[J].矿床地质,1:54-63.
张文兰.2004.赣南大吉山和漂塘花岗岩特征及成矿作用研究[D].南京大学:博士学位论文,75-80.
周云,梁新权,梁细荣,伍式崇,蒋英,温淑女,蔡永丰.2013.湖南锡田含W-Sn A型花岗岩年代学与地球化学特征[J].大地构造与成矿学,37(3):511-529.