地球化学省与地球化学边界

doi:10.11867/j.issn.1001-8166.2001.02.0153

根据中国大陆各种类型壳、幔源岩石和矿石的大量铅—锶—钕同位素资料,及全球特别是东亚大陆块体广泛的同位素与元素体系对比,发展了地球化学块体划分的同位素地球化学指标和填图方法。在此基础上开展了中国大陆的大尺度铅同位素矢量填图 ,确定了中国大陆主要地球化学省和地球化学急变带 (边界)。地球化学边界的形成与板块的斜结合以及结合以后岩石圈结构调整产生的克拉通边界密切相关。地球化学边界与重力正异常梯度带、莫霍面梯度带以及正负磁异常转换带存在平行和交错两种关系。研究表明地球化学急变带控制了中国大陆 90 %以上的超大型金、铜、锡、银、镍、铅—锌、铀、钾盐、硼、镁、磷等 (33个)和10个以上的大型矿集区。地球化学省划分制约着全球油气资源分布,而地球化学边界则具体控制着克拉通边缘前陆盆地中产油气位置。陆内六级以上强破坏性的浅源地震与克拉通边界——地球化学边界关系十分密切。喀斯特溶洞奇观的出现与地球化学边界关系同样相当密切。根据铅同位素地球化学填图确定的区域背景值可以对铅污染作出快速的定量评价。

关键词: 地球化学急变带, 地球化学省, 资源勘探评价, 环境与灾害

Based on great quantity of Pb Sr Nd isotopic data from various mantle and crust derived rocks and ores in Continental China, and global comparison of isotopic and element systematics, especially for the blocks in the eastern Asia, we developed the indexes and mapping methods of isotopic geochemistry for the division of geochemical provinces. The major geochemical provinces in Continental China and their geochemical steep zones, i.e. boundaries, have been established through large scale mapping of Pb isotopic vectors(the values in three dimensions space of ²⁰⁶Pb/ ²⁰⁴Pb, ²⁰⁷Pb/ ²⁰⁴Pb and ²⁰⁸Pb/ ²⁰⁴Pb).The generation of geochemical boundaries was tightly related to inclined combination of plates, as well as craton boundaries resulted in adjustment of lithosphere structure after plate collision. There are parallel or cross relationships between geochemical boundaries and gravity, Moho and magnet gradisnts. The division of geochemical provinces and establishment of their boundaries not only provide important basis for the paleo continent reconstruction and ascertaining plate boundaries, but also can be widely applied to exploration and evaluation of resources, establishment of environment background and pollution sources, as well as calamity forecasting. It is indicated from our study that the giant Au, Cu,Mo,Sn,Ag,Ni,Pb Zn,U,K salt,B,Mg and P deposits of about 90%, and more than 10 large concentrated mineralization districts in Continental China was controlled by the geochemical steep zones. The geochemical provinces constrained on distribution of global oil gas resources, whereas geochemical boundaries particularly controlled the sites of oil gas fields at the craton margins. There are tight relationships between strong destroying earthquakes with shallow sources and craton geochemical boundaries. The occurrence of karst caves and collapses is also closely related to the geochemical boundaries. As background values of Pb isotopes within a geochemical province is quite stable, based on the background values established by geochemical mapping, fast quantitative evaluation for Pb pollution level can be made.

Key words: Environment and calamity., Geonchemical steep zone, Geochemical Province, Resource exploration and evaluation

中图分类号:

[1] Zindler A. Nd,Sr and Pb isotopic systematics in a three component mantle, a new perspectiv[J].Nature,1982,289:519~523.
[2] Dupre B, Allehre C J. Pb-Sr isotope variations in Indian Ocean basalts and mixing phenomena[J].Nature,1983,303:142~146.
[3] Hart S R. A large-scale isotope anomaly in the southern hemisphere mantle[J]. Nature,1984,309:753~757.
[4] Castillo P R. The Dupal anomaly as a trace of the upwelling lower mantle[J]. Nature,1988,336:667~670.
[5] Klein E M,Langmuir C H,Zindler A,et al. Isotope evidence of a mantle convection boundary at the Australian-Antarctic discordance[J].Nature,1988,333:623~628.
[6] Mahoney J J, le Roex A P, Peng Z,et al. Southwestern limits of Indian Ocean ridge mantle and the origin of low206Pb/204Pb mid-ocean ridge basalt: isotope systematics of the central Southwest Indian Ridge (17~50°E)[J].J Geophy Res,1992,97:19 771~19 790.
[7] Mahoney J J, Frei R. Tejada M L G,et al. Tracing the Indian ocean mantle domain through time:Isotopic results from old west Indian,East Tethyan,and South Pacific seafloor[J].J Petrology,1998, 39:1 285~1 306.
[8] Pyle D G,Christie D M, Mahiney J J. Resolving an isotopic boundary within the Australian-Antarctic discordance [J].Earth Planet Sci Lett,1992,112:161~178.
[9] Hickey-Vrgas R.Origin of the Indian Ocean-type isotopic signature in basalts from Philippine Sea plate spreading centers:An assessment of local versus large-scale processes[J].J Geophy Res,1998,103(B9):20 963~20 979.
[10] Dosso L,Bougaukt H,Langmuir C,et al. The age and distribution of mantle heterogeneity along the mid Atlantic ridge (31~41°N)[J].Earth Planet Sci Lett,1999,170:269~286.
[11] Hofmann A W.Origin of the Hawaiian mantle plume[J].China Sci Bull,1998,43(Supp.):52.
[12] Humler E,Thirot J L, Montagner J P.Global correlations of mid-ocean-ridge basalts chemistry with seismic tomographic image[J].Nature,1993,364:225~228.
[13] Zhu B Q,Mao C X, Lugmair G W,et al.Isotopic and geochemical evidence for the origin of Plio-Pleistocene volcanic rocks near Indo-Eurasian collisional margin at Tengchong, China[J].Earth Planet Sci Lett,1983,65:263~275.
[14] Zhu B Q,Li X H, Liu B L. Three-component mixing and four system recycling models for explaining Nd-Sr-Pb isotopic correlation of suboceanic and subcontinental mantles[J].Science in China (B),1990,33:757~768.
[15] Zhu B Q, Wang H F. Geochronology of and Nd-Sr-Pb isotopic evidences for mantle source in the ancient subduction zone beneath Sanshui Basin,Guangdong Province,China[J].Chinese J of Geochemistry,1989,8(1):65~71.
[16] Zhu B Q.Evidence of isotopic systematics from crust and mantle for chemical heterogeneities of terranes[J].Chinese Science Bulletin,1991,36(15):1 279~1 282.
[17] Peng Z C,Zartman R E, Fuda E.et al. Pb-,Sr-,and Nd-iso-topic systematics and chemical characteristics of Cenozoic basalts,Eastern China[J].Chemical Geology,1986,59:3~33.
[18] Basu A R,Xie G H, Huang A K,et al.Major element,Ree, and Pb,Nd and Sr isotopic geochemistry of Cenozoic volcanic rocks of eastern China:implications for their origin from suboceanic-type mantle reservoirs [J]. Earth Planet Sci Lett,1991,105:149~169.
[19] Zhu Bingquan, Wang Huifen. NdˉSrˉPb isotopic and chemical evidence for the volcanism with MORB-OID source characteristics in the Leiqiong area[J].China,Geochimica,1989, (3):193~201.[朱炳泉,王慧芬.雷琼地区MORB-OIB过渡型地幔源的Nd-Sr-Pb同位素证据[J].地球化学,1989,(3):193~201.]
[20] Zhu Bingquan,Zhang Yuquan, Xie Yingwen.Nd,St and Pb isotopic characteristics of Cenozoic ultraˉpotassic volcanic rocks from eastern Erhai,Yunnan and their implications for subcontinent mantle evolution in southwestern China [J].Geochimica,1992,(3):201~212.[朱炳泉,张玉泉,谢应雯.滇西洱海第三纪超钾质火成岩系的Nd-Sr-Pb同位素特征与西南大陆地幔演化[J].地球化学,1992,(3):201~212.]
[21] Zhu Bingquan,Wang Huifen,Zou Liping,et al.Discussion on mantle geochemistry and division of Cathaysian-Yangtze mantle boundary in Zhe jiang-Fuzhou areas.In: Li Jiliang.Beijing:Metallurgic Industry Press,1993.60~68.[朱炳泉,王慧芬,邹丽萍,等.浙闽地幔地球化学与华南—扬子地幔边界划分讨论[A].见:李继亮主编.东南大陆岩石圈结构与地质演化[C].北京:冶金工业出版社,1993.60~68.]
[22] Liu Beiling, Chen Yuwei, Zhu Bingquan.Genesis of Cenozoic basalts in Jinbo Lake,N-E China,and its chemical feature of mantle,Nd,Sr,Pb isotopic and trace elemental evidence[J].Geochimica,1989,(1):9~19.[刘北玲,陈毓蔚,朱炳泉.东北镜泊湖新生代玄武岩的成因及其地幔化学特征——Sr、Nd、Pb同位素与微量元素证据[J].地球化学,1989,(1):9~19.]
[23] Zhang Benren,Lao T C,Gao S.Geochemical study of the lithosphere, tectonism and metallogenesis in the Qinling-Dabashan region [M]. Wuhan: China Univ Geosci Press,1994. [张本仁等.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.]
[24] Zhang Benren,Zhang Hongfei,Zhao Zhidan,et al.Geochemical subdivision and evoltuion of lithosphere in East Qinling and adjacent regions-Implication for tectonics[J].Science in china(D),1996,39(3):245~255.[张本仁,张宏飞,赵志丹,等.东秦岭及邻区壳、幔地球化学分区演化及其大地构造意义[J].中国科学(D),1996,26(3):201~208.]
[25] Yu J, Gui X. Isotope geochemistry of granitoids[A]. In: Tu G,Chow T. Isotope Geochemistry Research in China[C].Beijing: Science Press,1998.137~161.
[26] Li Shi,Wang Dang.Geochemistry of Granitoids in Tongbais-han-Dabishan,Central China[M].Wuhan:China Univ Geosci Press,1991.[李石,王丹.桐柏山—大别山花岗类地球化学[M].武汉:中国地质大学出版社,1991.]
[27] Zhang Ligang,et al.Block Geology of Eastern Asia Lithosphere[M].Beijing:Science Press,1995.[张理刚等.东南岩石圈块体地质[M].北京:科学出版社,1995.]
[28] Zhu B Q.Geochemical evidences for the southern China block being a part of Gondwana[J].J S Asian Earth Sci,1994,9:319~324.
[29] Zhu Bingquan.The mapping of geochemical provinces in China based on Pb isotopes[J].J Geochem Exploration,1995,55:171~181.
[30] Zhu Bingquan. Tri-dimension spatial topological diagrams of ore lead isotopes and their application to the division of geochemical provinces and mineralizations[J].Geochimica,1993,(3):210~216.[朱炳泉.矿石Pb同位素三维空间拓扑图解用于地球化学省与矿种区划[J].地球化学,1991,(3):210~216.]
[31] Yin A, Harrison T M. Geologic evolution of the Himalayan-Tibetan orogen[J]. Ann Rev Earth Planet Sci, 2000, (in press).
[32] Sengor A M. Evolution of the Altaid tectonic collage and Paleozoic crustal growth in Eurasia[J].Nature,1993,364:298~306.
[33] Wang Qianshen,Wu Chuanzhen,Liu Hongchen,et al.Discussion on distribution pattern of orustal thickness and crustal structure of Asian continent[J].Seismic Geology,1982,4(3):1~9.[王谦身,武传真,刘洪臣,等.亚洲大陆地壳厚度分布轮廓及地壳构造特征的探讨[J].地震地质,1982,4(3):1~9.]
[34] Liu Guangding.Discussion on Earth Sciences[J].Earth Science Frontiers,1998,5(1) 1~8.[刘光鼎.论地球科学[J].地学前缘,1998,5(1):1~8.]
[35] Yuan Xuecheng.Velocity structure of the Qinling lithosphere and mushroom cloud model[J].Science in China(D),39(3):235~244.[袁学诚.秦岭岩石圈速度结构与蘑菇云构造模型[J].中国科学(D),1996,26(3):209~215.]
[36] Xiong Shaobai, Lai Minghui,Liu Hongbin,et al.Lithosphere structure and velocity distribution in Tunxi-Wenzhou areas[A].In:Li Jiliang. Beijing:Metallurgic Industry Press,1993.250~256.[熊绍柏,赖明惠,刘宏宾,等.屯溪—温州地带的岩石圈结构与速度分布[A].见:李继亮主编.东南大陆岩石圈结构与地质演化[C].北京:冶金工业出版社,1993.250~256.]
[37] Yan Yafen,Ren Guotai,Zheng shuanggen.The relationship
between geomagnetic field feature and crustal structure for lithosphere in Southeast China[A].In:Li Jianged.BeijingL-Metallurgic Industry Press,1993,238~241.[闫雅芬,任国泰,郑双根.东南大陆岩石圈的地磁区域场特征与地壳结构的关系[A].见:李继亮主编.东南大陆岩石圈结构与演化[C].北京:冶金出版社,1993.238~241.]
[38] Jin Wenshan, Sun Dazhong. Deep crustal structure of South China continent and its evolution [M]. Beijing: Geological Press,1996.[金文山,孙大中.华南大陆深部地壳结构及其演化[M].北京:地质出版社,1993.]
[39] Wang Maoji.Gravity and geomzagnetic illustration of Heshan-Quanzhou profile[J].Geophysics Acta,1994,37(3):321~329.[王懋基.黑山—泉州地学断面的重磁解释[J].地球物理学报,1994,37(3):321~329.]
[40] Zhu B-Q, Dong Y-P, Chang X-Y,et al.Relation of isotopic geochemical steep zones with geophysical fields tectonics in the junction area of the Cathaysian, Yangtze and Indochia plates[J].Acta Geol Sinica,2000,74(2):236~240.
[41] Zhao Yonggui,Zhong Dalai, Liu Jianhua,et al.Principle of geological illustration of seismic tomography and its application to study on deep structure in western Yunnan[J].Geological Science,1992,(2):105~113.[赵永贵,钟大赍,刘建华,等.地震层析地质解释原理及其在滇西深部构造研究中的应用[J].地质科学,1992,(2):105~113.]
[42] Zhu B Q.Discussion on geochemical division and affinity of East Asia blocks:Implications for tectonic framework[A].In: Metcalfe I,ed.Gondwana Dispersion and Asian Accretion-Final Result of IUGS IGCP 321[C].Netherland,A A Balkema Pub,1998.211~227.
[43] Dong Y P, Zhu B Q,Chang X Y.Tectonic implications of the isotopic geochemical steep zone in eastern Yunnan,China[J].Chinese Sci Bull,1999,44(Supp.2):195~196.
[44] Dong Y P, Zhu B Q.Characteristics of the island—Arc pillow lavas from sortheast Yunnan Province,and its tectonic implications for paleo-tethys in south China[J].Chinese Sci Bull,2000,45(8):753~758.
[45] Zhu B Q,Chang S Y,Wang H F. The geochemical boundary between South China and Yangtze blocks and its constraint on the formation of super large deposits[J].Science in China(D),1996,39(1):58~65.
[46] Zhu B Q,Chang X Y, Qiu H N,et al.Characteristics of Proterozoic basements on the geochemical steep zones in the continent of China and their implications for setting of super large deposits[J]. Science in China (D),1998,41(Supp.):54~64.
[47] Zhang Z W, Zhu B Q,Cai K Q,et al. Lead isotopic steepdipping zone and mineralization—An example from mineral deposits contracted area in East Oinling China[J]. J China Univ Geosci,2000,11(1):287~294.
[48] Chang X Y, Zhu B-Q. Lead isotopic exploration intersecting mineralization zones for the depth forecast of concealed deposits—A case from Longbohe Cu deposit,Jinping,Yunnan Province, China[J].Science in China(D),2000,43(1):(in press).
[49] Chang Xiangyang,Zhu Bingquan,Sun Dazhong,et al.Isotope geochemistry study of Donghuan copper deposits in Middle Yunnan Province,SW China:I.Stratigraphic chronology and application of geochemical exploration by lead isotopes[J].Geochimica,1997,26(2):32~38.[常向阳,朱炳泉,孙大中,等.东川铜矿同位素地球化学研究:I.地层年代与铅同位素化探应用[J].地球化学,1997,26(2):32~38.]
[50] Zhu Bingquan,Zhang Jinglian.A study on distribution regularities of large-and medium size oil and gas fields in China mainland[J].Petroleum Explorationist,1999,4(1):12~17.[朱炳泉,张景廉.中国大陆大中型油气田分布规律探讨[J].勘探家,1999,4(1):12~17.]

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摘要

GEOCHEMICAL PROVINCES AND THEIR BOUNDARIES