小秦岭镰子沟金矿床辉钼矿Re-Os年龄和锆石U-Pb年龄及其地质意义
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摘要
镰子沟金矿床位于小秦岭金矿集区西部,矿体受断裂和石英脉体控制,围岩蚀变以钾化和硅化为主。矿床浅部以金矿为主,深部发现金钼(共)伴生矿体。为了确定镰子沟金矿床成岩、成矿时代,选择镰子沟金矿床正长斑岩和金钼矿石分别进行了LA-ICP-MS锆石U-Pb和辉钼矿Re-Os同位素研究。获得正长斑岩的~(207)Pb/~(206)Pb年龄加权平均值为1802.9±9.9Ma,此年龄明显早于小秦岭地区金矿床的形成时代;获得辉钼矿Re-Os等时线年龄为128.8±6.5Ma,指示矿床形成于早白垩世,晚于区域已知花岗岩形成时代。综合研究认为,镰子沟金矿床的形成与区域花岗岩无关,可能与深部流体或隐伏岩浆有关。
The Lianzigou gold deposit is located in the west of Xiaoqinling Au ore concentration area. The orebodies are hosted in the upper strata of Taihua Group and controlled by fault fracture zone or quartz veins. The wall rock alteration is dominated by potassium alteration and silicification. Au(Mo) orebodies have been discovered in the depth of the deposit. To constrain its petrogenic and metallgogenic ages, the authors carried out LA-ICP-MS zircon U-Pb dating on syenite porphyry and Re-Os dating on molybdenite, respectively. LA-ICP-MS zircon U-Pb dating of syenite porphyry gave a weighted average age of 1802.9±9.9 Ma,which is clearly older than the age of large-scale gold mineralization in the Xiaoqinling area. Re-Os dating on molybdenite from the Au orebodies gave an isochron age of 128.8±6.5 Ma, indicating that the Au and Mo mineralization occurred in Early Cretaceous. The Re-Os age is younger than the petrogenic ages of granites in the Xiaoqinling area, showing that there is no direct relationship between the known granitic magmatism and the mineralization of the Lianzigou Au deposit. Deep fluids or concealed magmatic intrusion probably played an important role in mineralization.
The Lianzigou gold deposit is located in the west of Xiaoqinling Au ore concentration area. The orebodies are hosted in the upper strata of Taihua Group and controlled by fault fracture zone or quartz veins. The wall rock alteration is dominated by potassium alteration and silicification. Au(Mo) orebodies have been discovered in the depth of the deposit. To constrain its petrogenic and metallgogenic ages, the authors carried out LA-ICP-MS zircon U-Pb dating on syenite porphyry and Re-Os dating on molybdenite, respectively. LA-ICP-MS zircon U-Pb dating of syenite porphyry gave a weighted average age of 1802.9±9.9 Ma,which is clearly older than the age of large-scale gold mineralization in the Xiaoqinling area. Re-Os dating on molybdenite from the Au orebodies gave an isochron age of 128.8±6.5 Ma, indicating that the Au and Mo mineralization occurred in Early Cretaceous. The Re-Os age is younger than the petrogenic ages of granites in the Xiaoqinling area, showing that there is no direct relationship between the known granitic magmatism and the mineralization of the Lianzigou Au deposit. Deep fluids or concealed magmatic intrusion probably played an important role in mineralization.
引文
[1]栾世伟，曹殿春，方耀奎，等.小秦岭金矿床地球化学[J].矿物岩石，1985,5(2):1-117.
[2]栾世伟，陈尚迪.小秦岭金矿主要控矿因素及成矿模式[J].地质找矿论丛，1990,5(5):1-14.
[3]胡正国，钱壮志，闫广民，等.小秦岭拆离-变质杂岩核构造与金矿[M].西安：陕西科学技术出版社，1994:21-122.
[4]黎世美，瞿伦全，苏振邦，等.小秦岭金矿地质和成矿预测[M].北京：地质出版社，1996:39-178.
[5]王相，唐荣扬，李实，等.秦岭造山与金属成矿[M].北京：冶金工业出版社，1996,123-145.
[6]卢欣祥，尉向东，董有，等.小秦岭—熊耳山地区金矿时代[J].黄金地质，1999,5(1):11-16.
[7]晁援.关于小秦岭金矿时代探讨[J].陕西地质，1989,7(1):52-56.
[8]胡受奚，林潜龙，陈泽铭，等.华北与华南古板块拼合带地质与成矿[M].南京：南京大学出版社，1988:1-558.
[9]祁进平，赖勇，任康绪，等.小秦岭金矿田成因的锶同位素约束[J].岩石学报，2006,22(10):2543-2550.
[10]冯建之，岳铮生，肖荣阁，等.小秦岭深部金矿成矿规律与成矿研究[M].北京：地质出版社，2009:44-252.
[11]卢欣祥，尉向东，于在平，等.小秦岭—熊耳山地区金矿的成矿流体特征[J].矿床地质，2003,22(4):377-386.
[12]Mao J W, Goldfarb R J, Zhang Z W, et al. Gold deposits in the Xiaoqinling-Xiong’ershan region, Qinling mountains central China[J]. Mineralium Deposita, 2002,37:306-325.
[13]蒋少涌，戴宝章，姜耀辉，等.胶东和小秦岭:两类不同构造环境中的造山型金矿省[J].岩石学报，2009,25(11):2727-2738.
[14]王义天，叶会寿，叶安旺，等.小秦岭文峪和娘娘山花岗岩体锆石SHRIMP U-Pb年龄及其意义[J].地质科学，2010,45(1):167-180.
[15]李栋，高毅，路卫东.小秦岭镰子沟蚀变岩型金矿地质特征及找矿标志[J].科技风，2014,4:67-69.
[16]王雷.小秦岭镰子沟金矿床地质地球化学特征与矿床成因探讨[D].中国地质大学（北京）硕士学位论文，2016:37-66.
[17]时毓，于津海，徐夕生，等.陕西小秦岭地区太华群的锆石U-Pb年龄和Hf同位素组成[J].岩石学报，2011,27(10):3095-3108.
[18]Su H M, Mao J W, He X R, et al. Timing of the formation of the Tianhuashan Basin in northern Wuyi as constrained by geochronology of volcanic and plutonic rocks[J]. Science China:Earth Sciences, 2013,56:940-955.
[19]Du A D, Wu S Q, Sun D Z, et al. Preparation and Certification of Re-Os Dating Reference Materials:Molybdenite HLP and JDC[J].Geostandard and Geoanalytical Research, 2004,28(1):41-52.
[20]李超，屈文俊，杜安道，等.含有普通锇的辉钼矿Re-Os同位素定年研究[J].岩石学报，2012,28(2):702-708.
[21]Stein H J, Scherstén A, Hannah J L, et al. Subgrain-scale decoupling of Re and187Os and assessment of laser ablation ICPMS spot dating in molybdenite[J]. Geochimica et Cosmochimica,2003,67:3673-3686.
[22]Ludwig K R. Isoplot/Ex, version 3.0:a geochronological tool kit for Microsoft Excel[M]. Berkeley Geochronology Center Special Publication, Berkeley, 2001.
[23]Luck J M, Allegre C J. The study of molybdenites through the187Re-187Os chronometer[J]. Earth Planet. Sci. Lett., 1982,61:291-296.
[24]杜安道，何红蓼，殷宁万，等.辉钼矿的铼-锇同位素地质年龄测定方法研究[J].地质学报，1994,68(4):339-347
[25]Martínez M C, Tudela A N. Archean lamprophyre dykes and gold mineralization, Matheson, Ontario:the conjunction of LILEenriched mafic magmas, deep crustal structures, and Au concentration[J]. Canadian Journal of Earth Sciences, 1986,23(23):324-343.
[26]Rock Amp N M S, Groves D I. Do lamprophyres carry gold as well as diamonds?[J]. Nature, 1988,332(6161):253-255.
[27]王团华，毛景文，王彦斌.小秦岭-熊耳山地区岩墙锆石SHRIMP年代学研究——秦岭造山带岩石圈拆沉的证据[J].岩石学报，2008,24(6):1273-1287.
[28]毕诗健，李建威，李占轲.华北克拉通南缘小秦岭金矿区基性脉岩时代及地质意义[J].地球科学，2011,36(1):17-32.
[29]赵太平，徐勇航，翟明国.华北陆块南部元古宙熊耳群火山岩的成因与构造环境：事实与争议[J].高校地质学报，2007,132(2):191-206.
[30]侯贵廷，李江海，刘玉琳，等.华北克拉通古元古代末的伸展事件:拗拉谷与岩墙群[J].自然科学进展，2005,15(11):1366-1373.
[31]唐克非.华北克拉通南缘熊耳山地区金矿床时空演化、矿床成因及成矿构造背景[D].中国地质大学（武汉）博士学位论文，2014:74-85.
[32]王义天，毛景文，卢欣祥，等.河南小秦岭金矿区Q875脉中深部矿化蚀变岩的40Ar-39Ar年龄及其意义[J].科学通报，2002,47(18):1427-1431.
[33]郭波，朱赖民，李犇，等.华北陆块南缘华山和合峪花岗岩岩体锆石U-Pb年龄、Hf同位素组成与成岩动力学背景[J].岩石学报，2009,25(2):265-281.
[34]朱赖民，张国伟，郭波，等.东秦岭金堆城大型斑岩钼矿床LAICP-MS锆石U-Pb定年及成矿动力学背景[J].地质学报，2008,82(2):204-220.
[35]王晓霞，王涛，齐秋菊，等.秦岭晚中生代花岗岩时空分布、成因演变及构造意义[J].岩石学报, 2011,27(6):1573-1593.
[36]Li J W, Bi S J, Selby D, et al. Giant Mesozoic gold provinces related to the destruction of the North China craton[J]. Earth&Planetary Science Letters, 2012,349(4):26-37.
[37]王秀璋，程景平，张宝贵，等.中国改造型金矿床地球化学[M].北京:科学出版社，1992:177.
[38]李诺，孙亚莉，李晶，等.小秦岭大湖金钼矿床辉钼矿铼锇同位素年龄及印支期成矿事件[J].岩石学报，2008,24(4):810-816.
[39]张进江，郑亚东，刘树文.小秦岭变质核杂岩的构造特征、形成机制及构造演化[M].北京：海洋出版社，1998:17-63.
[40]张本仁，骆庭川，高山，等.秦巴岩石圈构造及成矿规律地球化学研究[M].武汉：中国地质大学出版社，1994:1-466.
[41]代军治，钱壮志，高菊生，等.小秦岭镰子沟金矿床地质特征、黄铁矿原位硫同位素分析及成因[J].吉林大学学报（地球科学版），2018,48(6):1669-1682.
[42]毛景文，谢桂青，张作衡，等.中国北方中生代大规模成矿作用的期次及其地球动力学背景[J].岩石学报, 2005,31(1):169-188.
[2]栾世伟，陈尚迪.小秦岭金矿主要控矿因素及成矿模式[J].地质找矿论丛，1990,5(5):1-14.
[3]胡正国，钱壮志，闫广民，等.小秦岭拆离-变质杂岩核构造与金矿[M].西安：陕西科学技术出版社，1994:21-122.
[4]黎世美，瞿伦全，苏振邦，等.小秦岭金矿地质和成矿预测[M].北京：地质出版社，1996:39-178.
[5]王相，唐荣扬，李实，等.秦岭造山与金属成矿[M].北京：冶金工业出版社，1996,123-145.
[6]卢欣祥，尉向东，董有，等.小秦岭—熊耳山地区金矿时代[J].黄金地质，1999,5(1):11-16.
[7]晁援.关于小秦岭金矿时代探讨[J].陕西地质，1989,7(1):52-56.
[8]胡受奚，林潜龙，陈泽铭，等.华北与华南古板块拼合带地质与成矿[M].南京：南京大学出版社，1988:1-558.
[9]祁进平，赖勇，任康绪，等.小秦岭金矿田成因的锶同位素约束[J].岩石学报，2006,22(10):2543-2550.
[10]冯建之，岳铮生，肖荣阁，等.小秦岭深部金矿成矿规律与成矿研究[M].北京：地质出版社，2009:44-252.
[11]卢欣祥，尉向东，于在平，等.小秦岭—熊耳山地区金矿的成矿流体特征[J].矿床地质，2003,22(4):377-386.
[12]Mao J W, Goldfarb R J, Zhang Z W, et al. Gold deposits in the Xiaoqinling-Xiong’ershan region, Qinling mountains central China[J]. Mineralium Deposita, 2002,37:306-325.
[13]蒋少涌，戴宝章，姜耀辉，等.胶东和小秦岭:两类不同构造环境中的造山型金矿省[J].岩石学报，2009,25(11):2727-2738.
[14]王义天，叶会寿，叶安旺，等.小秦岭文峪和娘娘山花岗岩体锆石SHRIMP U-Pb年龄及其意义[J].地质科学，2010,45(1):167-180.
[15]李栋，高毅，路卫东.小秦岭镰子沟蚀变岩型金矿地质特征及找矿标志[J].科技风，2014,4:67-69.
[16]王雷.小秦岭镰子沟金矿床地质地球化学特征与矿床成因探讨[D].中国地质大学（北京）硕士学位论文，2016:37-66.
[17]时毓，于津海，徐夕生，等.陕西小秦岭地区太华群的锆石U-Pb年龄和Hf同位素组成[J].岩石学报，2011,27(10):3095-3108.
[18]Su H M, Mao J W, He X R, et al. Timing of the formation of the Tianhuashan Basin in northern Wuyi as constrained by geochronology of volcanic and plutonic rocks[J]. Science China:Earth Sciences, 2013,56:940-955.
[19]Du A D, Wu S Q, Sun D Z, et al. Preparation and Certification of Re-Os Dating Reference Materials:Molybdenite HLP and JDC[J].Geostandard and Geoanalytical Research, 2004,28(1):41-52.
[20]李超，屈文俊，杜安道，等.含有普通锇的辉钼矿Re-Os同位素定年研究[J].岩石学报，2012,28(2):702-708.
[21]Stein H J, Scherstén A, Hannah J L, et al. Subgrain-scale decoupling of Re and187Os and assessment of laser ablation ICPMS spot dating in molybdenite[J]. Geochimica et Cosmochimica,2003,67:3673-3686.
[22]Ludwig K R. Isoplot/Ex, version 3.0:a geochronological tool kit for Microsoft Excel[M]. Berkeley Geochronology Center Special Publication, Berkeley, 2001.
[23]Luck J M, Allegre C J. The study of molybdenites through the187Re-187Os chronometer[J]. Earth Planet. Sci. Lett., 1982,61:291-296.
[24]杜安道，何红蓼，殷宁万，等.辉钼矿的铼-锇同位素地质年龄测定方法研究[J].地质学报，1994,68(4):339-347
[25]Martínez M C, Tudela A N. Archean lamprophyre dykes and gold mineralization, Matheson, Ontario:the conjunction of LILEenriched mafic magmas, deep crustal structures, and Au concentration[J]. Canadian Journal of Earth Sciences, 1986,23(23):324-343.
[26]Rock Amp N M S, Groves D I. Do lamprophyres carry gold as well as diamonds?[J]. Nature, 1988,332(6161):253-255.
[27]王团华，毛景文，王彦斌.小秦岭-熊耳山地区岩墙锆石SHRIMP年代学研究——秦岭造山带岩石圈拆沉的证据[J].岩石学报，2008,24(6):1273-1287.
[28]毕诗健，李建威，李占轲.华北克拉通南缘小秦岭金矿区基性脉岩时代及地质意义[J].地球科学，2011,36(1):17-32.
[29]赵太平，徐勇航，翟明国.华北陆块南部元古宙熊耳群火山岩的成因与构造环境：事实与争议[J].高校地质学报，2007,132(2):191-206.
[30]侯贵廷，李江海，刘玉琳，等.华北克拉通古元古代末的伸展事件:拗拉谷与岩墙群[J].自然科学进展，2005,15(11):1366-1373.
[31]唐克非.华北克拉通南缘熊耳山地区金矿床时空演化、矿床成因及成矿构造背景[D].中国地质大学（武汉）博士学位论文，2014:74-85.
[32]王义天，毛景文，卢欣祥，等.河南小秦岭金矿区Q875脉中深部矿化蚀变岩的40Ar-39Ar年龄及其意义[J].科学通报，2002,47(18):1427-1431.
[33]郭波，朱赖民，李犇，等.华北陆块南缘华山和合峪花岗岩岩体锆石U-Pb年龄、Hf同位素组成与成岩动力学背景[J].岩石学报，2009,25(2):265-281.
[34]朱赖民，张国伟，郭波，等.东秦岭金堆城大型斑岩钼矿床LAICP-MS锆石U-Pb定年及成矿动力学背景[J].地质学报，2008,82(2):204-220.
[35]王晓霞，王涛，齐秋菊，等.秦岭晚中生代花岗岩时空分布、成因演变及构造意义[J].岩石学报, 2011,27(6):1573-1593.
[36]Li J W, Bi S J, Selby D, et al. Giant Mesozoic gold provinces related to the destruction of the North China craton[J]. Earth&Planetary Science Letters, 2012,349(4):26-37.
[37]王秀璋，程景平，张宝贵，等.中国改造型金矿床地球化学[M].北京:科学出版社，1992:177.
[38]李诺，孙亚莉，李晶，等.小秦岭大湖金钼矿床辉钼矿铼锇同位素年龄及印支期成矿事件[J].岩石学报，2008,24(4):810-816.
[39]张进江，郑亚东，刘树文.小秦岭变质核杂岩的构造特征、形成机制及构造演化[M].北京：海洋出版社，1998:17-63.
[40]张本仁，骆庭川，高山，等.秦巴岩石圈构造及成矿规律地球化学研究[M].武汉：中国地质大学出版社，1994:1-466.
[41]代军治，钱壮志，高菊生，等.小秦岭镰子沟金矿床地质特征、黄铁矿原位硫同位素分析及成因[J].吉林大学学报（地球科学版），2018,48(6):1669-1682.
[42]毛景文，谢桂青，张作衡，等.中国北方中生代大规模成矿作用的期次及其地球动力学背景[J].岩石学报, 2005,31(1):169-188.
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