陆内强碱性火山岩的成因：以山东无棣大山霞石岩为例
Genesis of intra-continental strongly alkaline volcanic rocks: A case study of Dashan nephelinites in Wudi, Shandong Province, North China
-
摘要: 本文以山东无棣的大山更新世霞石岩为例，通过全岩的元素地球化学和Sr-Nd-Hf同位素组成特征，探讨陆内强碱性幔源火山岩的成因及其源区特征。山东地区的新生代玄武岩主要分为早晚两期，早期以橄榄玄武岩为主，晚期以强碱性岩为主（包括霞石岩、碧玄岩等，常见地幔橄榄岩捕掳体）。大山霞石岩为晚期火山作用的代表，具有富碱和贫硅铝等强碱性火山岩的典型特征。在微量元素组成上，大山霞石岩以强烈富集轻稀土元素和大离子亲石元素，在原始地幔标准化图上以明显亏损Zr、Hf、Ti为特征(Hf/Hf*=0.66~0.68，Ti/Ti*=0.68~0.70)。其Sr-Nd-Hf同位素比值均一(87Sr/86Sr>=0.70333~0.70339，εNd=5.95~6.34，εHf>=8.26~8.43)，与早期玄武岩组成一个两端元混合的排列，其中大山霞石岩位于亏损端元一侧。在同位素组成相同的情况下，大山霞石岩相对山东新生代早期玄武岩具有明显偏低的Hf/Sm、Hf/Hf*、Ti/Ti*比值，说明源区残留矿物组合可以造成高场强元素Zr、Hf、Ti与稀土元素之间的明显分馏，暗示源区存在非橄榄岩组分。大山霞石岩相对橄榄岩来源熔体偏低的CaO含量和偏高的Zr/Hf比(47.9~48.4)，说明其源区残留过剩的单斜辉石，源岩中的非橄榄岩成分为辉石岩或角闪石岩。中等亏损的同位素组成特征说明这些非橄榄岩组分可能与该区显生宙的地壳重循环过程有关。Abstract: Here we report geochemical and Sr-Nd-Hf isotopic compositions of the Dashan nephelinites to discuss genesis and lithology of source for intra-continental strongly alkaline volcanic rocks. Two stages of the Cenozoic magmatism can be distinguished in Shandong Province, including early olivine basalts and late strongly alkaline rocks, e.g. nephelinites, basanites. Mantle xenoliths are common in the late alkaline basalts. The Dashan nephelinites are interpreted as the representative of the late magmatism in this area. They have typical signatures of continental alkaline basalts with low SiO2 and high alkali contents. In the primitive mantle-normalized spidergram, the Dashan nephelinites are characterized by enrichment in LREEs and LILEs, and depletion in Zr, Hf, Ti (Hf/Hf*=0.66~0.68，Ti/Ti*=0.68~0.70). They show a narrow range of isotopic compositions (87Sr/86Sr>=0.70333~0.70339,εNd=5.95~6.34,εHf>=8.26~8.43). Together with other Cenozoic basalts in Shandong Province, The Dashan nephelinites compose a two-endmember mixing array in the plots of 87Sr/86Sr> versus εNd and εNd versus εHf>.The Dashan nephelinites are located at the side near the depleted endmember. For a given εNd>or εHf> value, the Dashan nephelinites have obviously lower Hf/Sm, Hf/Hf*, Ti/Ti* ratios than those of the early basalts, which suggests a clear non-peridotitic source because their residual minerals can induce the fractionation between HFSEs (Zr, Hf, and Ti) and REEs. Low CaO contents for given MgO conents and superchondritic Zr/Hf ratios (47.9~48.4) indicate that there are excess clinopyroxene in the residue and the source rocks of the Dashan nephelinites are pyroxenite or hornblendite. The moderately depleted isotopic composition of the Dashan nephelinites suggests that these non-peridotitic components might be associated with crustal recycling during the Phanerozoic in the North China Craton.
-
Key words:
- Nephelinite /
- Crustal recycling /
- Pyroxenite /
- North China Craton
-
-
[1] Anders E,Grevesse N,Abundances of the elements-Meteoritic and solar,C eochim Cosmochim Acta,1989.
[2] Bureau of Geological and Mineral Resources of Shandoag Province,Regional Geology of Shandong Province,北京:地质出版社,1991.
[3] Chen DG,Peng ZC,K-Ar ages and Pb,Sr isotopic characteristics of Cenozoic volcanic rocks in Shandong,China,Geochimica,1985.
[4] Chen Y,Zhang Y,Graham D,Su S,Deng J,Geochemistry of Cenozoic basalts and mantle xenoliths in Northeast China,Lithos,2007.
[5] Dostal J,Zhi XC,Muehlenbachs K,Dupuy C,Zhai MZ,Geochemistry of Cenozoic alkali basaltic lavas from Shandong Province,eastern China,Geochemical Journal,1991.
[6] Farmer GL,Continental basaltic rocks,Treatise on Geochemistry,2003.
[7] Fu Yongtao.Li Anchun Petrology, Geochemistry and Nd-Sr-Pb Isotopic Properties of Volcanic Rocks in Daheishan Island, Penglai, Shandong Province [J].-海洋通报（英文版）2003(2)
[8] Hauri EH,Wagner TP,Grove TL,Experimental and natural partitioning of Th,U,Pb and other trace elements between garnet,clinopyroxene and basaltic melts,Cbem Geol,1994.
[9] Herzberg C,Petrology and thermal structure of the Hawaiian plume from Mauna Kea volcano,Nature,2006.
[10] Herzberg C,Asimow PD,Petrology of some oceanic island basalts:PRIMELT2. XLS software for primary magma calculation,Geochemistry Geophysics and Geosystems,2008.
[11] Hirschmann MM,Stolper EM,A possible role for garnet pyroxenite in the origin of the"garnet signature" in MORB,Contrib Minera Petrol,1996.
[12] Hirschmann MM,Kogiso T,Baker MB,Stolper EM,Alkalic magmas generated by partial melting of garnet pyroxenite,Geology,2003.
[13] Huang P,Fu YT,Li AC,Xiao SB,Geochimical characteristics of Dabeishan island alkalic volcanic rocks from Penglai,Shandong Province,Marine Science Bulletin,2007.
[14] Hofmann AW,Jochum KP,Seufert M,White WM,Nb and Pb in oceanic basalts:New constraints on mantle evolution,Earth and Planetary Science Letters,1986.
[15] Hofmann A,Chemical differentiation of the earth-The relationship between mantle,continental crust,and oceanic crust,Earth and Planetary Science Letters,1988.
[16] Jackson MC,Hart SR,Koppers AAP,Staudigel H,Konter J,Blusztajn J,Kurz M,Russell JA,The return of subducted continental crust in Samoan lavas,Nature,2007.
[17] Jin LY,K-Ar ages of Cenozoic volcanic rocks in the middle segment of the Tancheng-Lujiang Fault Zone and both sides,Shandong Geological Information,1983.
[18] 金隆裕 郯庐断裂带中段新生代火山岩的K-Ar年龄值和分期 [J].-地质论评1985(4)
[19] Kennedy AK,Lofgren GE,Wasserburg GJ,An experimental study of trace element partitioning between oldivine,orthopyroxene and melt in chondrules-equilibrium values and kinetic effects,Earth and Planetary Science Letters,1993.
[20] Klemme S,Prowatke S,Hametner K,G nther D,Partitioning of trace elements between rutile and silicate melts:Implications for subduction zones,Geochimica et Cosmochimica Acta,2005.
[21] Kogiso T,Hirschmann MM,Frost DJ,High-pressure partial melting of garnet pyroxenite:Possible mafic lithologies in the source of ocean island basalts,Earth and Planetary Science Letters,2003.
[22] 李献华.祁昌实.刘颖.梁细荣.涂湘林.谢烈文.杨岳衡 岩石样品快速Hf分离与MC-ICPMS同位素分析: 一个改进的单柱提取色谱方法 [J].-地球化学2005(2)
[23] Liu RX,Geochronology and geochemistry of Cenozoic volcanic rocks in eastern china,北京:地震出版社,1992.
[24] Liu Y,Gao S,Lee CTA,Hu S,Liu X Yuan H,Melt peridotite interactions:Links between garnet pyroxenite and high-Mg# signature of continental crust,Earth and Planetary Science Letters,2005.
[25] Liu Y,Gao S,Kelemen PB,Xu W,Recycled erust controls contrasting source compositions of Mesozoic and Cenozoic basalts in the North China Craton,Geochimica et Cosmochimica Acta,2008.
[26] McDonough WF,Sun SS,The composition of the Earth,Chemical Geology,1995.
[27] Niu Y,Collerson KD,Batiza R,Wendt IJ,Regelous M,Origin of E-type MORB at ridges far from mantle plumes:The East Pacific Rise at 11 20,Journal of Geophysical Research,1999.
[28] Niu Y,The origin of alkaline lavas,Science,2008.
[29] Nowell GM,Kempton PD,Noble SR,Fitton JG,Saunders AD,Mahoney,JJ,Taylor RN,High precision Hf isotope measurements of MORB and OIB by thermal ionisation mass spectrometry:Insights into the depleted mantle,Chemical Geology,1998.
[30] Peng ZC,Zartman RE,Futa K,Chen DG,Pb-,Sr-,and Ndisotopic systematics and chemical characteristics of Cenozoic basalts of eastern China,Chemical Geology,1986.
[31] Pertermann M,Hirschmann MM,Hametner K,G nther D Schmidt,MW,Experimental determination of trace element partitioning between garnet and silica-rich liquid during anhydrous partial melting of MORB-like eclogite,Geochemistry Geophysics and Geosystems,2004.
[32] Pilet S,Hernandez J,Bussy,Sylvester PJ,Short-term metasomatic control of Nb/Th ratios in the mantle sources of intraplate basalts,Geology,2004.
[33] Pilet S,Michael BB,Edward MS,Metasomatized lithosphere and the origin of alkaline lavas,Science,2008.
[34] Prytulak J,Elliott T,TiO2 enrichment in ocean island basalts,Earth and Planetary Science Letters,2007.
[35] 濮巍.高剑峰.赵葵东.凌洪飞.蒋少涌 利用DCTA和HIBA快速有效分离Rb-Sr、Sm-Nd的方法 [J].-南京大学学报（自然科学版）2005(4)
[36] Qiu JS,Hu J,Jiang SY,Wang RC,Xu XS,Mesozoic-Cenozoic magmatism in western Shandong Province and its implication for the chemical evolution of the mantle,Earth Science-Journal of China University of Gecociences,2005.
[37] Rapp RP,Shimizu N,Norman MD,Applegate GS,Reaction between slab-derived melts and peridotite in the mantle wedge:Experimental constraints at 3.8 GPa,Chemical Geology,1999.
[38] Sobolev AV,Hofmann AW,Sobolev SV,Nikogosian IK,An olivine-free mantle source of Hawaiian shield basalts,Nature,2005.
[39] Sebolev AV,Hofmann AW,Kuzmin DV,Yaxley GM,Arndt NT,Chung SL,Danyushevsky LV,Elliott T,Frey FA,Garcia MO,The amount of recycled crust in sources of mantle-derived melts,Science,2007.
[40] Sun Ss,McDonough WF,Chemical and isotopic systematics of oceanic basalt.s:Implications for mantle composition and processes,Geological Society London Special Publications,1989.
[41] Tang YJ,Zhang HF,Ying JF,Asthenosphere lithospheric mantle interaction in an extensional regime:Implication from the geochemistry of Cenozoic basalts from Taihang Mountains,North China Craton Chem Geol,2006.
[42] Van Westrenen W,Blundy J,Wood B,High field strength element/rare earth element fractionation during partial melting in the presence of garnet:Implications for identification of mantle heterogeneities,Geochemistry Geophysics and Geosystems,2001.
[43] Vervcort JD,Patchett PJ,Blichert-Toft J,Albarede E,Relationships between Lu-Hf and Sm-Nd isotopic systems in the global sedimentary system,Earth Planet Scil Lett,1999.
[44] Wang HF,Yang XC,Zhu BQ,Fan SK,Dai TM,K-Ar geochronology and evolution of Cenozoic volcanic rocks in Eastern China,Geochimica,1988.
[45] Wang HF,Zhu BQ,Zhang QF,A study on K-Ar isotopic ages of Cenozoic basalts from Linqu area,Shandong Province,Geochimica,1981.
[46] Weaver BL,Geochemistry of highly-undersaturated ocean island basalt suites from the South Atlantic Ocean:Fernando de Noronha and Trindade islands,Contrib Minera Petrol,1990.
[47] Yang YH,Zhang HF,Xie LW,Liu Y,Qi CS,Tu XL,Petrogeneses of typical Mesozoic and Cenozoic vocanic rocks from the North China Craton:New evidence from isotopic studies,Acta Petrologica Sinica,2006.
[48] Zhi XC,Trace element geochemistry and petrogenesis of Cenozoic alkalic basalts from the Penglai and Linqu areas,Shandong Province,Geological Review,1990.
[49] Zhi XC,Zhang ZQ,Wang JH,The neodymium and strontium isotopic compositions of Cenozoic alkalic basalts from Penglai and Linqu areas,Shandong Province,Geological Review,1994.
[50] Zindler A,Hart S,Chemical geodynamics,Annual Reviews in Earth and Planetary Sciences,1986.
[51] 陈道公.彭子成 山东新生代火山岩K-Ar年龄和Pb-Sr同位素 特征 [J].-地球化学1985
[52] 黄朋.付永涛.李安春.肖尚斌 山东蓬莱大黑山岛碱性火山岩地球化学特征 [J].-海洋与湖沼2007(1)
[53] 金隆裕,郯庐断裂带中断及其两侧新生代火山岩钾-氩年龄值,山东地质情报,1983.
[54] 金隆裕 郯庐断裂带中段新生代火山岩的K-Ar年龄值和分期 [J].-地质论评1985(4)
[55] 李献华.祁昌实.刘颖.梁细荣.涂湘林.谢烈文.杨岳衡 岩石样品快速Hf分离与MC-ICPMS同位素分析: 一个改进的单柱提取色谱方法 [J].-地球化学2005(2)
[56] 刘若新,中国新生代火山岩年代学与地球化学,北京:地震出版社,1992.
[57] 濮巍.高剑峰.赵葵东.凌洪飞.蒋少涌 利用DCTA和HIBA快速有效分离Rb-Sr、Sm-Nd的方法 [J].-南京大学学报(自然科学版)2005(4)
[58] 邱检生.胡建.蒋少涌.王汝成.徐夕生 鲁西中、新生代镁铁质岩浆作用与地幔化学演化 [J].-地球科学-中国地质大学学报2005(6)
[59] 山东省地质矿产局,山东省区域地质志,北京:地质出版社,1991.
[60] 王慧芬.朱炳泉.张前锋 山东临朐地区新生代玄武岩同位素 钾-氩年龄研究 [J].-地球化学1981
-
计量
- 文章访问数:
- PDF下载数:
- 施引文献: 0
下载: