新疆北山地区中坡山北镁铁质岩体岩石地球化学与岩石成因
Lithogeochemistry and petrogenesis of Zhongposhanbei maflc rock body, at Beishan region, Xinjiang
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摘要: 中坡山北镁铁质岩体位于新疆北山裂谷带的中带,岩体形态为相互联通的岩盆状,出露面积约180km~2。由角闪辉长岩、橄榄辉石岩、橄榄辉长岩、苏长辉长岩和斜长岩组成,岩相带呈同心环状展布,相互间呈渐变过渡关系。锆石U-Pb法同位素年龄为274+4Ma。岩相学、岩石化学、造岩矿物晶体化学和稀土元素地球化学特征均显示了非常发育的分离结晶作用。橄榄辉石岩和橄榄辉长岩主要由早期结晶相聚集而成,橄榄石是最初的液相线相,单斜辉石是数量最多的分离结晶相。斜长岩由残余岩浆结晶而成。母岩浆应该是高镁的拉斑玄武岩浆。Nd、Sr、Pb同位素组成和岩石地球化学特征充分证明了岩浆与围岩之间的物质交换。同化混染作用明显地改变了侵入岩的同位素组成和大离子亲石元素丰度。除斜长岩外,各种岩石的TiO_2、Na:O、K_2O、大离子亲石元素和稀土元素丰度均很低,受同化混染作用影响较小的样品的ε_Nd(t)=+6.80,这些特征证明其岩浆源区属亏损型地幔。FeO~*和SiO_2含量证明,熔融作用开始时,源岩为二辉橄榄岩;当熔融作用持续到一定程度时,源岩物质转化为方辉橄榄岩。稀土元素地球化学证明,熔融作用发生于尖晶石稳定域内。综合各方面要素可以证明,中坡山北岩体是塔里木板块二叠纪期间第四种类型地幔源区部分熔融的产物。
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[1] Arculus RJ and Johnson RW.1981. Island-arc magma sources:A geochemicalassessment of the roles of slab-derived components and crustal contamination.Geochemical Journal,15:109 -133
[2] 赵鹏大,胡旺亮.1995北山远景成矿区地物化综合研究与找矿靶区圈定,国家三0五项目研究报告
[3] 校培喜等.2005.笔架山幅1:25万区域地质调查(修测)k46c004002
[4] Barker JA,Menzies MA,Thirlwall MF and Macpherson C G.1997. Petrogenesis of Quaternary intraplate volcanism,Sana\'a Yenmen:Implication and polybaric melt hybridization.Journal of Petrology,38:1359-1390
[5] Campbell IH and Griffiths RW.1993. The evolution of mantle\'s chemical structrure.Lithos,30:389-399
[6] Cheng SD and Zhang XJ.2002. Geotectonic division of Xinjiang.Xinjiang Geology,8 (4) 53-62 (in Chinese)
[7] Frey FA,Green DH,et al.1978. Integrated models of basalt petrogenesis:A study of quarti tholeiites to olivine melilities from south eastern Australia utilizing geochemical and experimental petrological data.Journal of Petrology,19:463-513
[8] Furman TY,Bryce JG,et al.2004. East African rift system (EARS)plume structure:insight from quaternary mafic lavas of Turkana,Kenya.Journal of Petrology,45:1069-1088
[9] Gao ZJ,Chen JB,Lu SN et al.1993. Precambrian geology (No.6 the Precambrian geology in Northern Xinjiang).Beijing:Geological Publishing House,8 -40 (in Chinese)
[10] Green DH.1975. Genesis of archean peridotic magmas and constraints on archean geothermal gradients and tectonics.Geology,3:15-18
[11] Han BF,Ji JQ,Song B,Chen LH and Li ZG.2004. SHRIMP zircon U-Pb dating of the Kalatongke and Huangshandong mafic-ultramafic complex-bearing Cu-Ni ores,Xinjiang,and geological implications.Science bulletin of China,49 (22):2324-2328 (in chinese)
[12] Hess PC.1992. Phase equilibria constraints on the origin of ocean floor basalts.In:Morgan J P,Blackman D K & Sinton J M(eds).Mantle flow and Melt Generation at Mid-Ocean Ridges.Geophysical Monograph,American Geophysical Union,71:67 -102
[13] Henderson P.1984. Rare earth element geochemistry.Amsterdam:Elsevier Science Publishers B.V.,33 -54
[14] Hofmann W.1988. Chemical differentiation of the earth:the relationship between mantle,continental crust,and oceanic crust.Earth and Planetary Science Letters,90:297-314
[15] Hu WL and Zhou ZX.1992. Geophysical-chemical characteristics and ore potentiality of basic ultrabasic rock belt in Bijiashan,Beishan.Xinjiang Geology,10(2):167 -175 (in Chinese)
[16] Hunter AG.1998. Intracrustal controls on the coexistence of tholeiitic and calc-alkaline magma series at Aso Volcano,SW Japan.Journal of Petrology,39(7):1255-1284
[17] Jiang CY,Jia CZ,Li LC,Zhang PB,Lou DR and Bai KY.2004b.Source of the Fe-Riched-Type High-Mg Magma in Mazhartag Region,Xinjiang.Acta Geologica Sinica,78(6):770 -780(in Chinese with English abstract)
[18] Jiang CY,Zhang PB,Lu DR and Bai KY.2004c.Petrogenesis and magma source of the ultramafic rocks of permian at Wajilitag region,Western Tarim plate in Xijiang.Acta Petrologica Sinica,20 (6):1433 -1444 (in Chinese with English abstract)
[19] Jiang CY,Zhang PB,Lu DR,Bai KY,Wang YP,Tang SH,Wang JH and Yang C.2004a.Petrology,geochemistry and petrogenesis of the Kalpin basalts and their Nd,Sr and Pb isotopic compositions.Geological Review,50 (5):492-500 (in Chinese with English abstract)
[20] Mecdonald R,Rogers NW,Fitton J G et al.2001. Plume Lithosphere interactions in the generation of the basalts of the Kenya Rift,East Africa.Journal of Petrology,42:877-900
[21] O\'Hara MJ and Herzberg C.1998. Phase equilibrium constraints on the origin of basalts,picrites and komatiites.Earth-Science Reviews,44:39-79
[22] Rudnick R L and Fountain D M.1995. Nature and composition of the continental crust:a lower crustal perspective.Rev.Geophysics,33:267-309
[23] Spath A,Roex AP,et al.2001. Plume-lithosphere interaction and the origin of continental rift-related alkaline volcanism-the Chyulu Hills Volcanic Province,Southern Kenya.Journal of Petrology,42:765 -778
[24] Wasylenki LE and Baker MB.2003. Near-solidus melting of the shallow upper mantle:partial melting experiment on depleted peridotite.Journal of Petrology,7:1163-1191
[25] Wang K,Plant T et al.2002. A mantle melting profile across the basin and range,SW USA.Journal of Geophysical Research 107.10.1029/2001 JB000209
[26] Xiao YF,Wang DY,Wu DC,Deng JH and He ZW.2000. Geological evolution of the Western Beishan tectonic Belt of Xinjiang.Sichuan:Sciences and Xinjiang:Publishing House of Science,Technology and Hygiene,113-139 (in chinese)
[27] Zhang WS,et al.1992. Geotectonics and evolution characteristics of Beishan.Xinjiang Geology,10(2):129 -137 (in Chinese)
[28] Zhou MF,Lesher CM,Yang ZX,Li JW and Sun M.2004. Geochemistry and petrogenesis of 270 Ma Ni-Cu-(PGE) sulfide-bearing mafic intrusion in the Huangshan district,Easter Xinjiang,Northwest China:Implications for the tectonic evolution of the Central Asian orogenic belt.Chemical Geology,209:233 ~257
[29] Zhou JY,Cui BF,et al.2000. The rift evolution and Au ore-forming regular in east part of Beishan,Gansu and Xinjiang.Volcanology and Mineral Resources,21 (1):7-17 (in Chinese with English abstract)
[30] Zhou JY,et al.1996. Analysis on the Au,Ag,Cu minerogenetic conaition and target in east-north belt of Hongshijing-Beishan rift.Nanjing Institute of Geology and Mineral Resources,85-103 (in Chinese with English abstract)
[31] 成守德,张湘江.2000.新疆大地构造基本框架.新疆地质,18(4):53-62
[32] 高振家,陈晋镳,陆松年,彭昌文等.1993.前寒武纪地质(第6号,新疆北部前寒武纪).北京:地质出版社,8-40
[33] 韩宝福,季建清,宋彪,陈立辉,李宗怀.2004.新疆喀拉通克和黄山东含铜镍矿镁铁-超镁铁杂岩体的SHRIMP锆石U-Pb年龄及其地质意义.科学通报,49(22):2324-2328
[34] 胡旺亮,周治新.1992.北山笔架山地区基性-超基性岩带第五化特征及含矿性研究.新疆地质,10(2):167-175
[35] 姜常义,贾承造,李良辰,张蓬勃,卢登蓉,白开寅.2004 b.新疆麻扎尔塔格地区铁富集型高镁岩浆的源区.地质学报,78(6):770-780
[36] 姜常义,张蓬勃,卢登荣,白开寅.2004 c.新疆塔里木板块西部瓦吉里塔格地区二叠纪超镁铁岩的岩石成因与岩浆源区岩石学报,20(6):1433-1444
[37] 姜常义,张蓬勃,卢登蓉,白开寅,王瑶培,唐索寒,王进辉,杨淳.2004a.柯坪玄武岩的岩石学、地球化学、Nd、Sr、Pb同位素组成与岩石成因.地质论评,50(5):492-500
[38] 肖渊甫,王道永,吴德超,邓江红,何政伟.2000.新疆北山构造带西段地质演化.四川科学出版社和新疆科技卫生出版社,113-139
[39] 张旺生等.1992.新疆北山大地构造属性及演化特征.新疆地质,10(2):129-137
[40] 周济元,崔炳芳等.2000.甘新北山东段裂谷演化及金矿成矿规律.火山地质与矿产,21(1):7-17
[41] 周济元等.1996.红十井-北山裂谷带南亚带金银铜成矿条件研究及找矿靶区预测.南京地质矿产研究所,85-103
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