新疆青河县科克萨依金矿构造-流体演化
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摘要
科克萨依金矿位于新疆北部青河县境内,额尔齐斯构造-成矿带东南的布尔根地区。通过野外调查和室内综合研究,对其构造-蚀变、成矿流体进行了详细分析,讨论了构造-流体演化特征。研究表明:(1)金矿化与韧性剪切带的构造-蚀变作用密切相关,糜棱岩化强烈,强片理化、亚晶、变形纹、流动构造等结构发育。SEM-CL显示重结晶结构、溶解结构以及多期复合剪切结构特征,表明变形变质作用强烈。伴随构造-热液活动,硅化、黄铁矿化强烈,并具一定的空间分带,与金矿化关系密切。(2)包裹体类型有L_(H_2O)-V_(H_2O)、L_(H_2O)-L_(CO_2)、L_(H_2O)型三种,流体的演化表现为早期中高温、低盐度、富CO_2,随着中晚期阶段剪切带变形增强导致变形分解以及裂隙愈合,逐渐演化成中低温、低盐度的富H_2O流体。(3)科克萨依金矿具有造山型金矿特点,剪切带构造-热液蚀变为主要的控矿因素,其构造-成矿流体的演化特征与剪切带演化过程吻合。
The Kekesayi gold deposit is located in the Buergen ductile shear zone in the southern margin of Altay, Qinghe County, Xinjiang. The deposit consists of altered mylonite type and gold-bearing quartz veins type ores. The main ore-bearing rocks are gray metamorphic tuffs of the Tuoranggekuduke Formation. The ores are mostly lenticular and vein, and are strictly controlled by shear bands. Through field investigation, sample collection and laboratory identification, the structural alteration characteristics are studied in detail. The microstructure of quartz is analyzed by SEM cathodoluminescence(SEM-CL). The fluid inclusions of the deposit were studied by means of micro-temperature measurement and laser Raman analysis, and the tectonic-fluid evolution characteristics were discussed. Our results showed that:(1) The gold mineralization is closely related to the structural alteration of the ductile shear zone. The mylonitization, subgrain deformation and fluid structure are developed in the mining area. The recrystallized texture, dissolution structure and multistage composite shear structure characteristics of SEM-CL show that the deformation and metamorphism are very strong. The tectonic-hydrothermal activity resulted in strong silicification and pyritization and closely related to gold mineralization.(2) The fluid inclusions of quartz veins in the mineralized rocks are distributed in groups and the morphology of the fluid inclusions are mostly oval and tadpole in shape. The primary fluid inclusions are distributed in disorder, and the secondary fluid inclusions distribute linearly along the fissures mostly elongated owing to the strong tectonic deformation. Fluid inclusions are not of uniform size, generally are 8-20 μm. The types of inclusions can be classified according to the petrography and micro temperature measurement: two phase aqueous solution type(L_(H_2O)-V_(H_2O) ), carbon-rich type(L_(H_2O) -L_(CO_2) ) and single phase aqueous solution type(L_(H_2O) ). The evolution of the fluid is characterized by high temperature, low salinity and rich CO_2 in the early stage. As the deformation of the shear zone increases in the middle and late stages, the fluid evolved into low temperature, low salinity rich H_2O.(3) The Kekesayi gold deposit has the characteristics of orogenic gold deposit, and the evolutionary characteristics of tectonic-ore forming fluids are consistent with the evolution of shear zones. Structural alteration of shear zone is the main controlling factor of mineralization. And magmatic hydrothermal alteration may also play an important role in mineralization.
The Kekesayi gold deposit is located in the Buergen ductile shear zone in the southern margin of Altay, Qinghe County, Xinjiang. The deposit consists of altered mylonite type and gold-bearing quartz veins type ores. The main ore-bearing rocks are gray metamorphic tuffs of the Tuoranggekuduke Formation. The ores are mostly lenticular and vein, and are strictly controlled by shear bands. Through field investigation, sample collection and laboratory identification, the structural alteration characteristics are studied in detail. The microstructure of quartz is analyzed by SEM cathodoluminescence(SEM-CL). The fluid inclusions of the deposit were studied by means of micro-temperature measurement and laser Raman analysis, and the tectonic-fluid evolution characteristics were discussed. Our results showed that:(1) The gold mineralization is closely related to the structural alteration of the ductile shear zone. The mylonitization, subgrain deformation and fluid structure are developed in the mining area. The recrystallized texture, dissolution structure and multistage composite shear structure characteristics of SEM-CL show that the deformation and metamorphism are very strong. The tectonic-hydrothermal activity resulted in strong silicification and pyritization and closely related to gold mineralization.(2) The fluid inclusions of quartz veins in the mineralized rocks are distributed in groups and the morphology of the fluid inclusions are mostly oval and tadpole in shape. The primary fluid inclusions are distributed in disorder, and the secondary fluid inclusions distribute linearly along the fissures mostly elongated owing to the strong tectonic deformation. Fluid inclusions are not of uniform size, generally are 8-20 μm. The types of inclusions can be classified according to the petrography and micro temperature measurement: two phase aqueous solution type(L_(H_2O)-V_(H_2O) ), carbon-rich type(L_(H_2O) -L_(CO_2) ) and single phase aqueous solution type(L_(H_2O) ). The evolution of the fluid is characterized by high temperature, low salinity and rich CO_2 in the early stage. As the deformation of the shear zone increases in the middle and late stages, the fluid evolved into low temperature, low salinity rich H_2O.(3) The Kekesayi gold deposit has the characteristics of orogenic gold deposit, and the evolutionary characteristics of tectonic-ore forming fluids are consistent with the evolution of shear zones. Structural alteration of shear zone is the main controlling factor of mineralization. And magmatic hydrothermal alteration may also play an important role in mineralization.
引文
陈克强,党延霞,董永观.2010.新疆阿勒泰赛都金矿含金石英脉锆石U-Pb年龄及其地质意义.矿产勘查,1(3):229-233.
程忠富,芮行健.1996.哈巴河县赛都金矿成矿特征探讨.新疆地质,14(3):247-254.
邓吉牛,王军升,廖启林.2000.布尔根矿带金、铜找矿评价研究.国家三〇五项目资料.
李艳青,佘振兵,马昌前.2011.石英SEM-CL微结构及其在岩石学中的应用.地球科学进展,26(3):325-331.
邵世才,何绍勋.1994.剪切带型金矿床中含金石英脉的一种可能成生机制.大地构造与成矿学,18(2):155-162.
童英,王涛,Kovach V P,洪大卫,韩宝福.2006.阿尔泰中蒙边界塔克什肯口岸后造山富碱侵入岩体的形成时代、成因及其地壳生长意义.岩石学报,22(5):1267-1278.
汪劲草.1997.褶皱过程中含金石英脉形成的构造机制.地质论评,43(1):78-84.
王军升.2002.新疆科克萨依地区金矿控矿规律研究.矿床地质,21(S):674-677.
王军升,邓吉牛.1998.新疆科克萨依金矿控矿构造特征及找矿评价标志.有色金属矿产与勘查,7(5):283-288.
王军升,邓吉牛.1999a.新疆科克萨依地区金矿地质及矿床地球化学特征.地球学报,20(S):243-248.
王军升,邓吉牛.1999b.科克萨依金矿地质特征及矿床成因分析.有色金属矿产与勘查,8(6):530-535.
王伟涛,张复新,张健.2006.新疆多拉纳萨依金矿区构造特征与成矿关系.西北地质,39(3):7-11.
王燕海,徐九华,刘泽群,魏浩,丁汝褔,阴元军.2011.额尔齐斯成矿带萨尔布拉克金矿床的构造-成矿流体.地学前缘,18(5):55-66.
徐九华,张国瑞,谢玉玲,单立华,张绍俊,王平户,邹存海.2009.阿尔泰山南缘赛都金矿床的构造-成矿流体及其演化.岩石矿物学杂志,28(2):140-151.
闫升好,滕荣丽,王义天,陈文,张招崇,陈柏林.2006.新疆布尔根含金剪切带的40Ar/39Ar年龄及其地质意义.中国地质,33(3):648-655.
尹意求,李嘉兴,张积斌,陈大经,周志坚,胡庆雯,汪劲草.1998.新疆青河科克萨依韧性剪切带型金矿床的构造演化模式.矿床地质,17(4):314-320.
张湘炳,隋静霞,李志纯,刘伟,杨新岳,刘顺生,黄怀勇.1996,额尔齐斯构造带构造演化与成矿系列.北京:科学出版社,1-205.
赵玉社,张彬.2014.新疆富蕴县萨尔布拉克金矿地质特征及找矿标志.西北地质,47(2):156-163.
周刚,张招崇,谷高中,杨文平,何斌,张小林,罗世宾,王祥,贺永康.2006.新疆东准噶尔北部青格里河下游花岗岩类的时代及地质意义.现代地质,20(1):141-150.
周志坚.1994a.青河县科克萨依金矿成矿地质特征的研究.矿产与地质,43(8):398-401.
周志坚.1994b.新疆青河县科克萨依金矿金的赋存形态.贵金属地质,3(2):140-143.
Bernet M and Bassett K.2005.Provenance analysis by single-quartz-grain SEM-CL/optical microscopy.Journal of Sedimentary Research,75:492-500.
Bodnar R J.1993.Revised equation and table for determining the freezing-point depression of H2O-Na Cl solutions.Geochimica et Cosmochimica Acta,57(3):683-684.
Bonnemaison M and Marcoux E.1990.Auriferous mineralization in some shear-zones:A three-stage model of metallogenesis.Mineralium Deposita,25(2):96-104.
Groves D I,Goldfarb R J,Gebre-Mariam M,Hagemann S Gand Robert F.1998.Orogenic gold deposits:A proposed classification in the context of their crustal distribution and relationship to other gold deposit types.Ore Geology Reviews,13(1-5):7-27.
Müller A,RenéM,Behr H J and Kronz A.2003.Trace elements and cathodoluminescence of igneous quartz in topaz granites from the Hub Stock.Mineralogy and Petrology,79(3-4):167-191.
Seyedolali A,Krinsley D,Boggs S and Goles G G,1997.Provenance interpretation of quartz by scanning electron microscope-cathodoluminescence fabric analysis.Geology,25(9):787-790.
Shepherd T J,Rankin A H and Alderton D H M.1985.A practical guide to fluid inclusion studies.New York:Chapman and Hall:63-79.
Smedes H W.1973.Regional geologic setting of the boulder batholith,Montana.Economic Geology,68:907.
Rusk B G and Reed M H.2002.Scanning electron microscope-cathodoluminescence analysis of quartz reveals complex growth histories in veins from the Butte porphyry copper deposit.Montana Geology,30(8):727-730.
Rusk B G,Reed M H and Dilles J H.2006.Intensity of quartz cathodoluminescence and trace-element content in quartz from the porphyry copper deposit at Butte,Montana.American Mineralogist,91(8-9):1300-1312.
Van den Kerkhof A and Thiery R.2001.Carbonic inclusions.Lithos,55:49-68.
程忠富,芮行健.1996.哈巴河县赛都金矿成矿特征探讨.新疆地质,14(3):247-254.
邓吉牛,王军升,廖启林.2000.布尔根矿带金、铜找矿评价研究.国家三〇五项目资料.
李艳青,佘振兵,马昌前.2011.石英SEM-CL微结构及其在岩石学中的应用.地球科学进展,26(3):325-331.
邵世才,何绍勋.1994.剪切带型金矿床中含金石英脉的一种可能成生机制.大地构造与成矿学,18(2):155-162.
童英,王涛,Kovach V P,洪大卫,韩宝福.2006.阿尔泰中蒙边界塔克什肯口岸后造山富碱侵入岩体的形成时代、成因及其地壳生长意义.岩石学报,22(5):1267-1278.
汪劲草.1997.褶皱过程中含金石英脉形成的构造机制.地质论评,43(1):78-84.
王军升.2002.新疆科克萨依地区金矿控矿规律研究.矿床地质,21(S):674-677.
王军升,邓吉牛.1998.新疆科克萨依金矿控矿构造特征及找矿评价标志.有色金属矿产与勘查,7(5):283-288.
王军升,邓吉牛.1999a.新疆科克萨依地区金矿地质及矿床地球化学特征.地球学报,20(S):243-248.
王军升,邓吉牛.1999b.科克萨依金矿地质特征及矿床成因分析.有色金属矿产与勘查,8(6):530-535.
王伟涛,张复新,张健.2006.新疆多拉纳萨依金矿区构造特征与成矿关系.西北地质,39(3):7-11.
王燕海,徐九华,刘泽群,魏浩,丁汝褔,阴元军.2011.额尔齐斯成矿带萨尔布拉克金矿床的构造-成矿流体.地学前缘,18(5):55-66.
徐九华,张国瑞,谢玉玲,单立华,张绍俊,王平户,邹存海.2009.阿尔泰山南缘赛都金矿床的构造-成矿流体及其演化.岩石矿物学杂志,28(2):140-151.
闫升好,滕荣丽,王义天,陈文,张招崇,陈柏林.2006.新疆布尔根含金剪切带的40Ar/39Ar年龄及其地质意义.中国地质,33(3):648-655.
尹意求,李嘉兴,张积斌,陈大经,周志坚,胡庆雯,汪劲草.1998.新疆青河科克萨依韧性剪切带型金矿床的构造演化模式.矿床地质,17(4):314-320.
张湘炳,隋静霞,李志纯,刘伟,杨新岳,刘顺生,黄怀勇.1996,额尔齐斯构造带构造演化与成矿系列.北京:科学出版社,1-205.
赵玉社,张彬.2014.新疆富蕴县萨尔布拉克金矿地质特征及找矿标志.西北地质,47(2):156-163.
周刚,张招崇,谷高中,杨文平,何斌,张小林,罗世宾,王祥,贺永康.2006.新疆东准噶尔北部青格里河下游花岗岩类的时代及地质意义.现代地质,20(1):141-150.
周志坚.1994a.青河县科克萨依金矿成矿地质特征的研究.矿产与地质,43(8):398-401.
周志坚.1994b.新疆青河县科克萨依金矿金的赋存形态.贵金属地质,3(2):140-143.
Bernet M and Bassett K.2005.Provenance analysis by single-quartz-grain SEM-CL/optical microscopy.Journal of Sedimentary Research,75:492-500.
Bodnar R J.1993.Revised equation and table for determining the freezing-point depression of H2O-Na Cl solutions.Geochimica et Cosmochimica Acta,57(3):683-684.
Bonnemaison M and Marcoux E.1990.Auriferous mineralization in some shear-zones:A three-stage model of metallogenesis.Mineralium Deposita,25(2):96-104.
Groves D I,Goldfarb R J,Gebre-Mariam M,Hagemann S Gand Robert F.1998.Orogenic gold deposits:A proposed classification in the context of their crustal distribution and relationship to other gold deposit types.Ore Geology Reviews,13(1-5):7-27.
Müller A,RenéM,Behr H J and Kronz A.2003.Trace elements and cathodoluminescence of igneous quartz in topaz granites from the Hub Stock.Mineralogy and Petrology,79(3-4):167-191.
Seyedolali A,Krinsley D,Boggs S and Goles G G,1997.Provenance interpretation of quartz by scanning electron microscope-cathodoluminescence fabric analysis.Geology,25(9):787-790.
Shepherd T J,Rankin A H and Alderton D H M.1985.A practical guide to fluid inclusion studies.New York:Chapman and Hall:63-79.
Smedes H W.1973.Regional geologic setting of the boulder batholith,Montana.Economic Geology,68:907.
Rusk B G and Reed M H.2002.Scanning electron microscope-cathodoluminescence analysis of quartz reveals complex growth histories in veins from the Butte porphyry copper deposit.Montana Geology,30(8):727-730.
Rusk B G,Reed M H and Dilles J H.2006.Intensity of quartz cathodoluminescence and trace-element content in quartz from the porphyry copper deposit at Butte,Montana.American Mineralogist,91(8-9):1300-1312.
Van den Kerkhof A and Thiery R.2001.Carbonic inclusions.Lithos,55:49-68.