赣南浅变质岩岩石地球化学特征及稀土成矿潜力研究
|
摘要
赣南地区浅变质岩系分布广泛,且风化壳发育,查明浅变质岩的岩石学及地球化学特征对分析离子吸附型稀土矿床的成矿潜力具有重要作用,而目前关于变质岩离子吸附型稀土矿的研究资料较少。本文对区内广泛发育的新元古代—寒武纪浅变质岩进行采样,通过岩相学、岩石地球化学等方法对赣南浅变质岩进行分类研究。结果表明:赣南浅变质岩时代跨度大,从青白口系至泥盆系以及少量侏罗系均有出露,以新元古代面积最广,主要类型有变砂岩类、变质凝灰岩类、板岩类、千枚岩类及片岩类。其中,变砂岩类和变质凝灰岩类的稀土含量高(∑REEs平均值分别为302μg/g和246μg/g),LREEs/HREEs=2.68~5.43,目前查明的稀土矿物主要为独居石和磷钇矿。区内变质凝灰岩类产出厚度较大,稀土含量较高,风化壳发育,是良好的离子吸附型稀土矿的成矿母岩类型。千枚岩类和片岩类的平均稀土含量(∑REEs>224μg/g)次之,但由于岩石风化难度较大,形成稀土风化壳型矿体可能性偏低。本研究是对变质岩离子吸附型稀土矿成矿的初步探讨,旨在为今后进一步的研究和找矿工作提供基础资料和依据。
Epimetamorphic rocks and related weathered crusts are widely distributed in South Jiangxi province.Identifying the petrological and geochemical characteristics of epimetamorphic rocks has a significant effect on the metallogenetic potential analysis on ion-adsorption REEs deposits.At present,there is little research about the metamorphic rock ion-adsorbed rare earth deposits.Epimetamorphic rocks of Neoproterozoic to Cambrian age are widely distributed in this region.Petrological and geochemical methods are used to classify these epimetamorphic rocks.Results show that the epimetamorphic rocks in this region have a large age span,ranging from Qingbaikou to Devonian.Minor epimetamorphic rocks also occur in Jurassic strata.Neoproterozoic epimetamorphic rocks are most widespread and mainly include blastopsammite,metamorphic tuff,slate,phyllite,and schist.Blastopsammite and metamorphic tuff have the highest REEs content with average contents of 302 μg/g and 246 μg/g,respectively,and show the LREE enrichment patterns with LREEs/HREEs of 2.68-5.43.Monazite and xenotime are the two most common rare earth minerals found in the epimetamorphic rocks so far.The metamorphic tuffs in the area have a large outcrop thickness,high REE content and well-weathered crusts,which are good metallogenic parent rocks for ion-adsorbed rare earth deposits.Phyllite,schist and granulite have lower REE contents(> 224 μg/g,on average),but they are resistant to weathering and thus have a low potential in forming REE ore bodies.This study was a preliminary discussion of ion-adsorption rare earth deposits related to epimetamorphic parent rocks,which provides basic information and reference for further studies and prospecting.
Epimetamorphic rocks and related weathered crusts are widely distributed in South Jiangxi province.Identifying the petrological and geochemical characteristics of epimetamorphic rocks has a significant effect on the metallogenetic potential analysis on ion-adsorption REEs deposits.At present,there is little research about the metamorphic rock ion-adsorbed rare earth deposits.Epimetamorphic rocks of Neoproterozoic to Cambrian age are widely distributed in this region.Petrological and geochemical methods are used to classify these epimetamorphic rocks.Results show that the epimetamorphic rocks in this region have a large age span,ranging from Qingbaikou to Devonian.Minor epimetamorphic rocks also occur in Jurassic strata.Neoproterozoic epimetamorphic rocks are most widespread and mainly include blastopsammite,metamorphic tuff,slate,phyllite,and schist.Blastopsammite and metamorphic tuff have the highest REEs content with average contents of 302 μg/g and 246 μg/g,respectively,and show the LREE enrichment patterns with LREEs/HREEs of 2.68-5.43.Monazite and xenotime are the two most common rare earth minerals found in the epimetamorphic rocks so far.The metamorphic tuffs in the area have a large outcrop thickness,high REE content and well-weathered crusts,which are good metallogenic parent rocks for ion-adsorbed rare earth deposits.Phyllite,schist and granulite have lower REE contents(> 224 μg/g,on average),but they are resistant to weathering and thus have a low potential in forming REE ore bodies.This study was a preliminary discussion of ion-adsorption rare earth deposits related to epimetamorphic parent rocks,which provides basic information and reference for further studies and prospecting.
引文
[1]白鸽,吴澄宇,丁孝石,等.南岭地区离子型稀土矿床形成条件和分布规律[R].北京:地质矿产部矿床地质研究所,1989.Bai G,Wu C Y,Ding X S,et al.The Forming Condition and Distribution Law of Ionic Type Rare-Earth Ore Deposit in Nanling Region[R].Beijing:Institute of Ore Deposit Geology,1989.
[2]Bern C R,Yesavage T,Foley N K.Ion-adsorption REEs in regolith of the Liberty Hill pluton,South Carolina,USA:An effect of hydrothermal alteration[J].Journal of Geochemical Exploration,2017,172:29-40.
[3]王登红,赵芝,于扬,等.我国离子吸附型稀土矿产科学研究和调查评价新进展[J].地球学报,2017,38(3):317-325.Wang D H,Zhao Z,Yu Y,et al.A review of the achievements in the survey and study of ion-adsorption type REE in China[J].Acta Geoscientica Sinica,2017,38(3):317-325.
[4]Sanematsu K,Murakami H,Watanabe Y,et al.Enrichment of rare elements(REE)in granitic rocks and their weathered crusts in central and southern Laos[J].Bulletin of the Geological Survey of Japan,2009,60(11/12):527-558.
[5]Foley N,Ayuso R.REE enrichment in granite-derived regolith deposits of the Southeastern United States:Prospective source rocks and accumulation processes[J].British Columbia Geological Survey Paper,2015,3:131-138.
[6]Murakami H,Ishihara S.REE mineralization of weathered crust and clay sediment on granitic rocks in the Sanyo Belt,SW Japan and the Southern Jiangxi Province,China[J].Resource Geology,2008,58(4):373-401.
[7]Ishihara S,Hua R,Hoshino M,et al.REE abundance and REE minerals in granitic rocks in the Nanling Range,Jiangxi Province,Southern China,and generation of the REE-rich weathered crust deposits[J].Resource Geology,2008,58(4):355-372.
[8]Maulana A,Yonezu K,Watanabe K.Geochemistry of rare earth elements(REE)in the weathered crusts from the granitic rocks in Sulawesi Island,Indonesia[J].Journal of Earth Science,2014,25(3):460-472.
[9]杨岳清,胡淙声,罗展明.离子吸附型稀土矿床成矿地质特征及找矿方向[J].中国地质科学院院报矿床地质研究所分刊,1981:102-118.Yang Y Q,Hu Z S,Luo Z M.Geological characteristics of mineralization of rare earth deposits of the ion-absorption type and their prospecting direction[J].Bulletin of the Chinese Academy of Geological Sciences,1981:102-118.
[10]Bao Z W,Zhao Z H.Geochemistry of mineral with exchangeable REY in the weathering crusts of granitic rocks in South China[J].Ore Geology Reviews,2008,33:519-535.
[11]Sanematsu K,Watanabe Y.Characteristics and Genesis of Ion Adsorption-type Rare Earth Element Deposits[C]//Verplanck P L,Hitzman M W.Reviews in Economic Geology Vol.18.Society of Economic Geologists.2016:55-79.
[12]吴澄宇.风化壳稀土成矿作用——一种不平衡过程[J].矿床地质,1989,8(4):85-90.Wu C Y.Rare earth mineralization in weathering crust—A nonequilibrium process[J].Mineral Deposits,1989,8(4):85-90.
[13]王登红,陈毓川,陈郑辉,等.南岭地区矿产资源形势分析和找矿方向研究[J].地质学报,2007,81(7):882-890.Wang D H,Chen Y C,Chen Z H,et al.Assessment on mineral resource in Nanling region and suggestion for further prospecting[J].Acta Geologica Sinica,2007,81(7):882-890.
[14]王登红,赵芝,于扬,等.离子吸附型稀土资源研究进展、存在问题及今后研究方向[J].岩矿测试,2013,32(5):796-802.Wang D H,Zhao Z,Yu Y,et al.Progress,problems and research orientation of ion-adsorption type rare earth resources[J].Rock and Mineral Analysis,2013,32(5):796-802.
[15]王登红,陈毓川,王瑞江,等.对南岭与找矿有关问题的探讨[J].矿床地质,2013,32(4):854-863.Wang D H,Chen Y C,Wang R J.Disscussion on some problems related to prospecting breakthrough in Nanling region[J].Mineral Deposits,2013,32(4):854-863.
[16]宋云华,沈丽璞.江西某酸性火山岩风化壳中粘土矿物及其形成条件的讨论[J].矿物学报,1982(3):207-212.Song Y H,Shen L P.Discussion of clay minerals and forming conditions in some acidic volcanic weathering crusts in Jiangxi Province[J].Acta Mineralogica Sinica,1982(3):207-212.
[17]张祖海.华南风化壳离子吸附型稀土矿床[J].地质找矿论丛,1990,5(1):57-71.Zhang Z H.A study on weathering crust ion adsorption type REEdeposits,South China[J].Contribution to Geology and Mineral Resource Research,1990,5(1):57-71.
[18]华仁民,张文兰,顾晟彦,等.南岭稀土花岗岩、钨锡花岗岩及其成矿作用的对比[J].岩石学报,2007,23(10):2321-2328.Hua R M,Zhang W L,Gu S Y,et al.Comparison between REE granite and W-Sn granite in the Nanling region,South China,and their mineralizations[J].Acta Petrologica Sinica,2007,23(10):2321-2328.
[19]赵芝,王登红,陈振宇,等.南岭东段与稀土矿有关岩浆岩的成矿专属性特征[J].大地构造与成矿学,2014,38(2):255-263.Zhao Z,Wang D H,Chen Z Y,et al.Metallogenic specialization of rare earth mineralized igneous rocks in the Eastern Nanling Region[J].Geotectonica et Metallogenia,2014,38(2):255-263.
[20]刘邦秀,刘春根,邱永泉.江西南部鹤仔片麻状花岗岩类Pb-Pb同位素年龄及地质意义[J].火山地质与矿产,2001,22(4):264-268.Liu B X,Liu C G,Qiu Y Q.The Pb-Pb isotopic ages and geologic significance of gneissic granite in Hezi,Jiangxi[J].Volcanology&Mineral Resources,2001,22(4):264-268.
[21]王丽娟,于津海,O’Reilly S Y,等.华夏南部可能存在Grenville期造山作用:来自基底变质岩中锆石U-Pb定年及Lu-Hf同位素信息[J].科学通报,2008,53(14):1680-1692.Wang L J,Yu J H,O’Reilly S Y,et al.Grenvillian orogeny in the Southern Cathaysia Block:Constraints from U-Pb ages and Lu-Hf isotopes in zircon from metamorphic basement[J].Chinese Science Bulletin,2008,53(14):1680-1692.
[22]于津海,王丽娟,O’Reilly S Y,等.赣南存在古元古代基底:来自上犹陡水煌斑岩中捕虏锆石的U-Pb-Hf同位素证据[J].科学通报,2009,54(7):898-905.Yu J H,Wang L J,O’Reilly S Y,et al.Paleoproterozoic basement beneath the Southern Jiangxi Province:Evidence from U-Pb ages and Lu-Hf isotopes in zircons from the Doushui lamprophyre[J].Chinese Science Bulletin,2009,54(7):898-905.
[23]靳松,张利,钟增球,等.浙闽地区华夏地块新元古代变沉积岩地球化学特征及其地质意义[J].地球科学——中国地质大学学报,2008,33(6):764-774.Jin S,Zhang L,Zhong Z Q,et al.Geochemical characteristics and geological implications for the Neoproterozoic meta-sedimentary rocks of the Cathaysia block in Zhejiang and Fujian Province[J].Earth Science—Journal of China University of Geosciences,2008,33(6):764-774.
[24]王仁民,贺高品,陈珍珍,等.变质岩原岩图解判别法[M].北京:地质出版社,1987:1-51.Wang R M,He G P,Chen Z Z,et al.Graphic Method for Protolith Metamorphic Rocks[M].Beijing:Geological Publishing House,1987:1-51.
[25]Shaw D M.The origin of the Apsley gneiss,Ontario[J].Canadian Journal of Earth Sciences,1972,9:18-35.
[26]赵芝,王登红,刘新星,等.广西花山岩体不同风化阶段稀土元素特征及其影响因素[J].稀土,2015,36(3):14-20.Zhao Z,Wang D H,Liu X X,et al.Geochemical features of rare earth elements in different weathering stage of the Guangxi Huashan granite and its influence factors[J].Chinese Rare Earths,2015,36(3):14-20.
[27]池汝安,田君,罗仙平,等.风化淋积型稀土矿的基础研究[J].有色金属科学与工程,2012,3(4):1-13.Chi R A,Tian J,Luo X P,et al.The basic research on the weathered crust elution-deposited rare earth ores[J].Nonferrous Metals Science and Engineering,2012,3(4):1-13.
[28]宋云华,沈丽璞,王贤觉.某些岩石风化壳中稀土元素的初步探讨[J].科学通报,1987,32(9):695-698.Song Y H,Shen L P,Wang X J.Preliminary discussion of rare earth elements in some weathering crusts[J].Chinese Science Bulletin,1987,32(9):695-698.
[29]包志伟.华南花岗岩风化壳稀土元素地球化学研究[J].地球化学,1992(2):166-174.Bao Z W.A geochemical study of the granitoid weathering crust in Southeast China[J].Geochimica,1992(2):166-174.
[2]Bern C R,Yesavage T,Foley N K.Ion-adsorption REEs in regolith of the Liberty Hill pluton,South Carolina,USA:An effect of hydrothermal alteration[J].Journal of Geochemical Exploration,2017,172:29-40.
[3]王登红,赵芝,于扬,等.我国离子吸附型稀土矿产科学研究和调查评价新进展[J].地球学报,2017,38(3):317-325.Wang D H,Zhao Z,Yu Y,et al.A review of the achievements in the survey and study of ion-adsorption type REE in China[J].Acta Geoscientica Sinica,2017,38(3):317-325.
[4]Sanematsu K,Murakami H,Watanabe Y,et al.Enrichment of rare elements(REE)in granitic rocks and their weathered crusts in central and southern Laos[J].Bulletin of the Geological Survey of Japan,2009,60(11/12):527-558.
[5]Foley N,Ayuso R.REE enrichment in granite-derived regolith deposits of the Southeastern United States:Prospective source rocks and accumulation processes[J].British Columbia Geological Survey Paper,2015,3:131-138.
[6]Murakami H,Ishihara S.REE mineralization of weathered crust and clay sediment on granitic rocks in the Sanyo Belt,SW Japan and the Southern Jiangxi Province,China[J].Resource Geology,2008,58(4):373-401.
[7]Ishihara S,Hua R,Hoshino M,et al.REE abundance and REE minerals in granitic rocks in the Nanling Range,Jiangxi Province,Southern China,and generation of the REE-rich weathered crust deposits[J].Resource Geology,2008,58(4):355-372.
[8]Maulana A,Yonezu K,Watanabe K.Geochemistry of rare earth elements(REE)in the weathered crusts from the granitic rocks in Sulawesi Island,Indonesia[J].Journal of Earth Science,2014,25(3):460-472.
[9]杨岳清,胡淙声,罗展明.离子吸附型稀土矿床成矿地质特征及找矿方向[J].中国地质科学院院报矿床地质研究所分刊,1981:102-118.Yang Y Q,Hu Z S,Luo Z M.Geological characteristics of mineralization of rare earth deposits of the ion-absorption type and their prospecting direction[J].Bulletin of the Chinese Academy of Geological Sciences,1981:102-118.
[10]Bao Z W,Zhao Z H.Geochemistry of mineral with exchangeable REY in the weathering crusts of granitic rocks in South China[J].Ore Geology Reviews,2008,33:519-535.
[11]Sanematsu K,Watanabe Y.Characteristics and Genesis of Ion Adsorption-type Rare Earth Element Deposits[C]//Verplanck P L,Hitzman M W.Reviews in Economic Geology Vol.18.Society of Economic Geologists.2016:55-79.
[12]吴澄宇.风化壳稀土成矿作用——一种不平衡过程[J].矿床地质,1989,8(4):85-90.Wu C Y.Rare earth mineralization in weathering crust—A nonequilibrium process[J].Mineral Deposits,1989,8(4):85-90.
[13]王登红,陈毓川,陈郑辉,等.南岭地区矿产资源形势分析和找矿方向研究[J].地质学报,2007,81(7):882-890.Wang D H,Chen Y C,Chen Z H,et al.Assessment on mineral resource in Nanling region and suggestion for further prospecting[J].Acta Geologica Sinica,2007,81(7):882-890.
[14]王登红,赵芝,于扬,等.离子吸附型稀土资源研究进展、存在问题及今后研究方向[J].岩矿测试,2013,32(5):796-802.Wang D H,Zhao Z,Yu Y,et al.Progress,problems and research orientation of ion-adsorption type rare earth resources[J].Rock and Mineral Analysis,2013,32(5):796-802.
[15]王登红,陈毓川,王瑞江,等.对南岭与找矿有关问题的探讨[J].矿床地质,2013,32(4):854-863.Wang D H,Chen Y C,Wang R J.Disscussion on some problems related to prospecting breakthrough in Nanling region[J].Mineral Deposits,2013,32(4):854-863.
[16]宋云华,沈丽璞.江西某酸性火山岩风化壳中粘土矿物及其形成条件的讨论[J].矿物学报,1982(3):207-212.Song Y H,Shen L P.Discussion of clay minerals and forming conditions in some acidic volcanic weathering crusts in Jiangxi Province[J].Acta Mineralogica Sinica,1982(3):207-212.
[17]张祖海.华南风化壳离子吸附型稀土矿床[J].地质找矿论丛,1990,5(1):57-71.Zhang Z H.A study on weathering crust ion adsorption type REEdeposits,South China[J].Contribution to Geology and Mineral Resource Research,1990,5(1):57-71.
[18]华仁民,张文兰,顾晟彦,等.南岭稀土花岗岩、钨锡花岗岩及其成矿作用的对比[J].岩石学报,2007,23(10):2321-2328.Hua R M,Zhang W L,Gu S Y,et al.Comparison between REE granite and W-Sn granite in the Nanling region,South China,and their mineralizations[J].Acta Petrologica Sinica,2007,23(10):2321-2328.
[19]赵芝,王登红,陈振宇,等.南岭东段与稀土矿有关岩浆岩的成矿专属性特征[J].大地构造与成矿学,2014,38(2):255-263.Zhao Z,Wang D H,Chen Z Y,et al.Metallogenic specialization of rare earth mineralized igneous rocks in the Eastern Nanling Region[J].Geotectonica et Metallogenia,2014,38(2):255-263.
[20]刘邦秀,刘春根,邱永泉.江西南部鹤仔片麻状花岗岩类Pb-Pb同位素年龄及地质意义[J].火山地质与矿产,2001,22(4):264-268.Liu B X,Liu C G,Qiu Y Q.The Pb-Pb isotopic ages and geologic significance of gneissic granite in Hezi,Jiangxi[J].Volcanology&Mineral Resources,2001,22(4):264-268.
[21]王丽娟,于津海,O’Reilly S Y,等.华夏南部可能存在Grenville期造山作用:来自基底变质岩中锆石U-Pb定年及Lu-Hf同位素信息[J].科学通报,2008,53(14):1680-1692.Wang L J,Yu J H,O’Reilly S Y,et al.Grenvillian orogeny in the Southern Cathaysia Block:Constraints from U-Pb ages and Lu-Hf isotopes in zircon from metamorphic basement[J].Chinese Science Bulletin,2008,53(14):1680-1692.
[22]于津海,王丽娟,O’Reilly S Y,等.赣南存在古元古代基底:来自上犹陡水煌斑岩中捕虏锆石的U-Pb-Hf同位素证据[J].科学通报,2009,54(7):898-905.Yu J H,Wang L J,O’Reilly S Y,et al.Paleoproterozoic basement beneath the Southern Jiangxi Province:Evidence from U-Pb ages and Lu-Hf isotopes in zircons from the Doushui lamprophyre[J].Chinese Science Bulletin,2009,54(7):898-905.
[23]靳松,张利,钟增球,等.浙闽地区华夏地块新元古代变沉积岩地球化学特征及其地质意义[J].地球科学——中国地质大学学报,2008,33(6):764-774.Jin S,Zhang L,Zhong Z Q,et al.Geochemical characteristics and geological implications for the Neoproterozoic meta-sedimentary rocks of the Cathaysia block in Zhejiang and Fujian Province[J].Earth Science—Journal of China University of Geosciences,2008,33(6):764-774.
[24]王仁民,贺高品,陈珍珍,等.变质岩原岩图解判别法[M].北京:地质出版社,1987:1-51.Wang R M,He G P,Chen Z Z,et al.Graphic Method for Protolith Metamorphic Rocks[M].Beijing:Geological Publishing House,1987:1-51.
[25]Shaw D M.The origin of the Apsley gneiss,Ontario[J].Canadian Journal of Earth Sciences,1972,9:18-35.
[26]赵芝,王登红,刘新星,等.广西花山岩体不同风化阶段稀土元素特征及其影响因素[J].稀土,2015,36(3):14-20.Zhao Z,Wang D H,Liu X X,et al.Geochemical features of rare earth elements in different weathering stage of the Guangxi Huashan granite and its influence factors[J].Chinese Rare Earths,2015,36(3):14-20.
[27]池汝安,田君,罗仙平,等.风化淋积型稀土矿的基础研究[J].有色金属科学与工程,2012,3(4):1-13.Chi R A,Tian J,Luo X P,et al.The basic research on the weathered crust elution-deposited rare earth ores[J].Nonferrous Metals Science and Engineering,2012,3(4):1-13.
[28]宋云华,沈丽璞,王贤觉.某些岩石风化壳中稀土元素的初步探讨[J].科学通报,1987,32(9):695-698.Song Y H,Shen L P,Wang X J.Preliminary discussion of rare earth elements in some weathering crusts[J].Chinese Science Bulletin,1987,32(9):695-698.
[29]包志伟.华南花岗岩风化壳稀土元素地球化学研究[J].地球化学,1992(2):166-174.Bao Z W.A geochemical study of the granitoid weathering crust in Southeast China[J].Geochimica,1992(2):166-174.