内蒙古赤峰岱王山金矿田石英二长岩中角闪石、斜长石化学成分特征及地质意义
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摘要
岱王山金矿田位于赤峰—朝阳金矿带东部,是古亚洲洋闭合事件形成的造山型金矿床。对金矿田成矿时代、空间分布及矿床地质特征的研究表明,石英二长岩岩体是成矿母岩体。利用电子探针对石英二长岩中的角闪石和斜长石进行了化学成分分析及相关参数计算,结果表明:角闪石属于钙质角闪石中的铁韭闪石,斜长石为更长石和中长石;利用角闪石、斜长石化学成分估算的岩浆成岩压力为1.38×10~8~2.66×10~8Pa、深度为5.20~10.04 km、温度为627℃~760℃、lg f_(O2)为-19.2~-15.5,表明成岩环境具有高温、高压和高氧逸度的特征。角闪石化学成分揭示岩浆的物质来源具有壳、幔混源的特征,是板块俯冲背景下由地幔楔与大陆地壳物质混熔形成。石英二长岩较高的成岩温度、压力和氧逸度条件,有利于Au元素在岩浆期后的成矿流体中富集,是成矿的有利岩石。
The Daiwangshan Gold Field is located in the eastern part of Chifeng-Chaoyang gold ore belt,which is an orogenic gold deposit formed by the closure of the paleo Asian Ocean. Through the study of the metallogenic epoch,spatial distribution and geological characteristics of the gold field,it is shown that the adamellite rock mass is the metallogenic parent rock mass. By means of EPMA,the compositions of the amphibole and plagioclase in the adamellite rock are analyzed and the correlated parameters are calculated. It shows that the amphibole belongs to ferropargasite in the calcic amphiboles,the plagioclase is attributed to oligoclase and andesine; based on the mineral chemical composition of the amphibole and plagioclase in the adamellite rock,it's calculated that the magmatic diagenetic pressure is 1. 38 × 108-2. 66 × 108 Pa,depth is 5. 20-10. 04 km,temperature is 627 ℃-760 ℃ and the lg fO2 is-19. 2--15. 5,indicating that the diagenetic environment is characterized by high temperature,high pressure and high oxygen fugacity. The chemical composition of amphibole revals that magma has the characteristics of a mixed source of crust and mantle,as which was formed by mixing the mantle wedge and the continental crust molten material in the plate subduction background. The high diagenetic temperature,pressure and oxygen fugacity of the adamellite are propitious to the enrichment of Au elements in the ore-forming fluid in post magmatic period,which is a favorable rock mass for the mineralization.
The Daiwangshan Gold Field is located in the eastern part of Chifeng-Chaoyang gold ore belt,which is an orogenic gold deposit formed by the closure of the paleo Asian Ocean. Through the study of the metallogenic epoch,spatial distribution and geological characteristics of the gold field,it is shown that the adamellite rock mass is the metallogenic parent rock mass. By means of EPMA,the compositions of the amphibole and plagioclase in the adamellite rock are analyzed and the correlated parameters are calculated. It shows that the amphibole belongs to ferropargasite in the calcic amphiboles,the plagioclase is attributed to oligoclase and andesine; based on the mineral chemical composition of the amphibole and plagioclase in the adamellite rock,it's calculated that the magmatic diagenetic pressure is 1. 38 × 108-2. 66 × 108 Pa,depth is 5. 20-10. 04 km,temperature is 627 ℃-760 ℃ and the lg fO2 is-19. 2--15. 5,indicating that the diagenetic environment is characterized by high temperature,high pressure and high oxygen fugacity. The chemical composition of amphibole revals that magma has the characteristics of a mixed source of crust and mantle,as which was formed by mixing the mantle wedge and the continental crust molten material in the plate subduction background. The high diagenetic temperature,pressure and oxygen fugacity of the adamellite are propitious to the enrichment of Au elements in the ore-forming fluid in post magmatic period,which is a favorable rock mass for the mineralization.
引文
[1]冯德胜.内蒙古敖汉旗岱王山金矿床地球化学特征及矿床成因[D].长春:吉林大学,2014.
[2]LEAKE B E,WOOLLEY A R,ARPS C E S,et al.Nomenclature of amphiboles:report of the subcommittee on amphiboles of the International Mineralogical Association,Commission on New Minerals and Mineral Names[J].The Canadian Mineralogist,1997,35:219-246.
[3]DEER W A.An introduction to rock-forming minerals[J].Longman Scientific and Technical,1992,66(25):509-517.
[4]HAMMARSTROM J M,ZEN E.Aluminum in hornblende;an empirical igneous geobarometer[J].Amer Mineral,1986,71(11):1 297-
[5]HOLLISTER L S,GRISSOM G C,PETERS E K,et al.Confirmation of the empirical correlation of Al in hornblende with pressure of solidification of calc-alkaline plutons[J].American Mineralogist,1987,72(3):231-239.
[6]JOHNSON M C,RUTHERFORD M J.Experimental calibration of the aluminum-in-hornblende geobarometer with application to Long Valley caldera(California)volcanic rocks[J].Geology,1989,17(2):837-841.
[7]SCHMIDT M W.Amphibole composition in tonalite as a function of pressure:an experimental calibration of the Al-in-hornblende barometer[J].Contributions to Mineralogy&Petrology,1992,110(2/3):304-310.
[8]ANDERSON J L,SMITH D R.The effects of temperature and fO2on the Al-in-hornblende barometer[J].American Mineralogist,1995,80(5/6):549-559.
[9]HOLLAND T,BLUNDY J.Non-ideal interactions in calcic amphiboles and their bearing on amphibole-plagioclase thermometry[J].Contributions to Mineralogy&Petrology,1994,116(4):433-447.
[10]RIDOLFI F,RENZULLI A,PUERINI M.Stability and chemical equilibrium of amphibole in calc-alkaline magmas:an overview,new thermobarometric formulations and application to subductionrelated volcanoes[J].Contributions to Mineralogy and Petrology,2010,160(1):45-66.
[11]DADA O.Application of amphibole chemistry in determining the petrogenesis of hornblende-biotite granites from toro complex,northcentral,nigeria[J].Continental Journal of Earth Sciences,2013,8(1):1-11.
[12]COLTORTI M,BONADIMAN C,FACCINI B,et al.Amphiboles from suprasubduction and intraplate lithospheric mantle[J].Lithos,2007,99(1):68-84.
[13]刘世伟.内蒙古敖汉旗岱王山金矿田中井金矿床地球化学特征及成因[D].长春:吉林大学,2018.
[14]谢应雯,张玉泉.横断山区花岗岩类中角闪石的标型特征及其成因意义[J].矿物学报,1990,10(1):35-45.
[15]李锦轶,高立明,孙桂华,等.内蒙古东部双井子中三叠世同碰撞壳源花岗岩的确定及其对西伯利亚与中朝古板块碰撞时限的约束[J].岩石学报,2007,23(3):565-582.
[16]李双林,欧阳自远.兴蒙造山带及邻区的构造格局与构造演化[J].海洋地质与第四纪地质,1998,18(3):46-55.
[17]王五力,郭胜哲.中国东北古亚洲与古太平洋构造域演化与转换[J].地质与资源,2012,21(1):27-34.
[18]付乐兵.华北克拉通北缘赤峰—朝阳地区中生代构造岩浆演化与金成矿[D].武汉:中国地质大学(武汉),2012.
[19]孙珍军.华北克拉通北缘赤峰—朝阳地区金矿成矿作用研究[D].长春:吉林大学,2013.
[20]陈光远,孙岱生,邵伟.胶东郭家岭花岗闪长岩成因矿物学与金矿化[M].武汉:中国地质大学出版社,1993.
[21]赛盛勋,赵天明,王中亮,等.玲珑黑云母花岗岩成因:矿物学特征约束[J].岩石学报,2016,32(8):2 477-2 493.
[22]陆丽娜,范宏瑞,胡芳芳,等.胶西北郭家岭花岗闪长岩侵位深度:来自角闪石温压计和流体包裹体的证据[J].岩石学报,2011,27(5):1 521-1 532.
[23]杨阳,王晓霞,于晓卫,等.胶西北中生代花岗岩中黑云母和角闪石成分特征及成岩成矿意义[J].岩石学报,2017,33(10):3 123-3 136.
[2]LEAKE B E,WOOLLEY A R,ARPS C E S,et al.Nomenclature of amphiboles:report of the subcommittee on amphiboles of the International Mineralogical Association,Commission on New Minerals and Mineral Names[J].The Canadian Mineralogist,1997,35:219-246.
[3]DEER W A.An introduction to rock-forming minerals[J].Longman Scientific and Technical,1992,66(25):509-517.
[4]HAMMARSTROM J M,ZEN E.Aluminum in hornblende;an empirical igneous geobarometer[J].Amer Mineral,1986,71(11):1 297-
[5]HOLLISTER L S,GRISSOM G C,PETERS E K,et al.Confirmation of the empirical correlation of Al in hornblende with pressure of solidification of calc-alkaline plutons[J].American Mineralogist,1987,72(3):231-239.
[6]JOHNSON M C,RUTHERFORD M J.Experimental calibration of the aluminum-in-hornblende geobarometer with application to Long Valley caldera(California)volcanic rocks[J].Geology,1989,17(2):837-841.
[7]SCHMIDT M W.Amphibole composition in tonalite as a function of pressure:an experimental calibration of the Al-in-hornblende barometer[J].Contributions to Mineralogy&Petrology,1992,110(2/3):304-310.
[8]ANDERSON J L,SMITH D R.The effects of temperature and fO2on the Al-in-hornblende barometer[J].American Mineralogist,1995,80(5/6):549-559.
[9]HOLLAND T,BLUNDY J.Non-ideal interactions in calcic amphiboles and their bearing on amphibole-plagioclase thermometry[J].Contributions to Mineralogy&Petrology,1994,116(4):433-447.
[10]RIDOLFI F,RENZULLI A,PUERINI M.Stability and chemical equilibrium of amphibole in calc-alkaline magmas:an overview,new thermobarometric formulations and application to subductionrelated volcanoes[J].Contributions to Mineralogy and Petrology,2010,160(1):45-66.
[11]DADA O.Application of amphibole chemistry in determining the petrogenesis of hornblende-biotite granites from toro complex,northcentral,nigeria[J].Continental Journal of Earth Sciences,2013,8(1):1-11.
[12]COLTORTI M,BONADIMAN C,FACCINI B,et al.Amphiboles from suprasubduction and intraplate lithospheric mantle[J].Lithos,2007,99(1):68-84.
[13]刘世伟.内蒙古敖汉旗岱王山金矿田中井金矿床地球化学特征及成因[D].长春:吉林大学,2018.
[14]谢应雯,张玉泉.横断山区花岗岩类中角闪石的标型特征及其成因意义[J].矿物学报,1990,10(1):35-45.
[15]李锦轶,高立明,孙桂华,等.内蒙古东部双井子中三叠世同碰撞壳源花岗岩的确定及其对西伯利亚与中朝古板块碰撞时限的约束[J].岩石学报,2007,23(3):565-582.
[16]李双林,欧阳自远.兴蒙造山带及邻区的构造格局与构造演化[J].海洋地质与第四纪地质,1998,18(3):46-55.
[17]王五力,郭胜哲.中国东北古亚洲与古太平洋构造域演化与转换[J].地质与资源,2012,21(1):27-34.
[18]付乐兵.华北克拉通北缘赤峰—朝阳地区中生代构造岩浆演化与金成矿[D].武汉:中国地质大学(武汉),2012.
[19]孙珍军.华北克拉通北缘赤峰—朝阳地区金矿成矿作用研究[D].长春:吉林大学,2013.
[20]陈光远,孙岱生,邵伟.胶东郭家岭花岗闪长岩成因矿物学与金矿化[M].武汉:中国地质大学出版社,1993.
[21]赛盛勋,赵天明,王中亮,等.玲珑黑云母花岗岩成因:矿物学特征约束[J].岩石学报,2016,32(8):2 477-2 493.
[22]陆丽娜,范宏瑞,胡芳芳,等.胶西北郭家岭花岗闪长岩侵位深度:来自角闪石温压计和流体包裹体的证据[J].岩石学报,2011,27(5):1 521-1 532.
[23]杨阳,王晓霞,于晓卫,等.胶西北中生代花岗岩中黑云母和角闪石成分特征及成岩成矿意义[J].岩石学报,2017,33(10):3 123-3 136.