胡琳;刘显凡;邓江红;彭博;徐窑窑;李慧;田晓敏;

• 1:成都理工大学地球科学学院
• 2:中国地质大学(武汉)地质过程与矿物资源国家重点实验室
• 3:中国地质科学院地质力学研究所

摘要(Abstract)：

通过对云南保山二叠纪卧牛寺玄武岩(P1w)的地球化学、岩相学及构造环境等的研究,利用电子探针、地球化学等方法进行了岩石样品检测,显示该套玄武岩w(SiO2)为46.14%~54.12%,w(MgO)为1.84%~7.69%,w(K2O+Na2O)为0.38%~9.75%,且w(Na2O)>w(K2O),为钠质碱性玄武岩系列;轻稀土元素相对富集重稀土元素相对亏损,LREE/HREE=4.81~7.6,轻重稀土元素分异较为明显,Eu无明显异常(δEu=0.91~1.04),表明其岩浆在演化过程中斜长石分离结晶很弱,所有样品较强富集Pb,强烈亏损K、P、Ti、Rb和Sr,Ba元素丰度有明显波动。综合研究认为,该套玄武岩为富集地幔石榴石橄榄岩10%~30%部分熔融的产物,形成于大陆裂谷边缘拉张环境,岩浆源于富集地幔的部分熔融并沿断裂通道快速运移至地表迅速凝固的过程中,未经历明显分异或与其他物质的相互作用。

关键词(KeyWords)： 二叠纪;卧牛寺组玄武岩;地球化学;形成环境;云南保山

Abstract:

Keywords:

基金项目(Foundation): 中国地质调查局地质调查项目(12120113048700)

作者(Author): 胡琳;刘显凡;邓江红;彭博;徐窑窑;李慧;田晓敏;

Email:

参考文献(References)：

• [1]肖龙,徐义刚,梅厚钧,等.云南保山卧牛寺组玄武岩成因:地幔柱活动的产物[J].岩石矿物学杂志,2003,22(1):20-28.
• [2]侯增谦,莫宣学,朱勤文,等.“三江”古特提斯地幔热柱:洋岛玄武岩证据[J].地球学报,1996,17(4):343-361.
• [3]刘善印,钟大赉,吴根耀.滇西南景谷-镇沅地区第三纪重力流沉积及其地质意义[J].沉积学报,1998,16(2):50-54.
• [4]黄勇,郝家栩,邓贵标,等.滇西施甸地区二叠纪卧牛寺组大陆溢流玄武岩的发现[J].地质通报,2012,31(2):314-320.
• [5]莫宣学,潘桂棠.从特提斯到青藏高原形成:构造-岩浆事件的约束[J].地学前缘,2006,13(6):43-51.
• [6]李朋武,高锐,崔军文,等.西藏和云南三江地区特提斯洋盆演化历史的古地磁分析[J].地球学报,2005,26(5):3-20.
• [7]邱家骧,林景仟.岩石化学[M].北京:地质出版社,1991.
• [8]丁振举,刘丛强,姚书振,等.东沟坝多金属矿床矿质来源的稀土元素地球化学限制[J].吉林大学学报:地球科学版,2003,33(4):437-442.
• [9]Xu Y G,Chung S L,Jahn B M,et al.Petrologic and geochemicalconstrains on the petrogenesis of Permian-Triassic Emeishan flood basalts in southwestern China[J].Lithos,2001,58:145-168.
• [10]Stanley C R,Russel J K.Petrologic hypothesis testing with pearce element ration diagrams derivation of diagram axes[J].Contributions to Mineralogy and Petrology,1989,103(1):78-89.
• [11]Peate D W,Pearce J A,Hawkesworth C J,et al.Geochemical variations in Vanuatu arc iavas:The fole of subducted material and variable mantle wedge compositon[J].Journal of Petrology,1997,38(10):1331-1358.
• [12]Mahoney J J,Jones W B,Frey F A,et al.Geochemical characteristics of lavas from Broken Ridge,the Naturaliste Plateau in the southernmost Kerguelen Plateau:Cretaceous Plateau volcanism in the southeast Indian Ocean[J].Chemical Geology,1995,120(3/4):315-345.
• [13]Pearce J A.Trace element characteristics of lavas from destructive plate boumdaries[C]∥Thorpe R S.Orogenic Andesites&Related Rocks.Chichester,England:[s.n.],1982:525-548.
• [14]Yang Jianjun,Godard G,Kienast J R,et al.Ultrahigh-pressure(60kbar)magnesite-bearing garnet peridotites from northeastern Jiangsu,China[J].Journal of Geology,1993,101(5):541-554.
• [15]Zou H B,Zindler A,Xu X S,et al.Major,trace element and Nd,Sr and Pb isotope studies of Cenozoic basalts in SE China:Mantle sources,regional variation,and tectonic significance[J].Chemical Geology,2000,171(1/2):33-47.
• [16]Patino Douce A E,McCarthy T C.Melting of crustal rocks during continental collision and subduction[M].Netherlands:Kluwer Academic Publishers,1998:2-55.
• [17]Defant M J,Drummond M S.Mount St Helens:Potential example of the partial melting of the subducted lithosphere in a volacanic arc[J].Geology,1993,21(6):547-550.
• [18]Mecdonald R,Rogers N W,Fitton J G.Plume lithosphere interaction in the generation of the basalats of the Kenya Rift,East Africa[J].Journal of Petrology,2001,42(5):877-900.
• [19]李春辉,刘显凡,赵甫峰,等.云南马关火山角砾岩及其包体岩石岩相学和元素地球化学特征及其地质意义[J].地质科技情报,2011,30(3):48-56.
• [20]Johnson K T M.Experimental determination of partition coefficients for rare earth and high-field-strength elements between clinopyroxene,garnet,and basaltic melt at high pressure[J].Contrib.Mineral.Petrol.,2000,133(1/2):60-68.
• [21]Kelemen P B,Hanghoj K,Greene A R.One view of the geochemistry of subduction-related magmatic arcs,with an emphasis on primitive andesite and lower crust[J].Treatise on Geochemitry,2014,4:749-806.
• [22]Munker C.Nb/Ta fractionation in a Cambrian arc/back system,New Zealand:Source constraints and application of refined ICPMS techniques[J].Chemical Geology,1998,144(1/2):23-45.
• [23]Barker J A,Menzies M A,Thirlwall M F,et al.Petrogenesis of Quaternary intraplate volvanism.Sana,a Yenmen:Implicaion and polybaric melt hybridization[J].Journal of Petrology,1997,38(10):1359-1390.
• [24]Peter Olson,张昌明.来自深部地幔的超级热柱[J].地质科技情报,1993,12(2):39-47.
• [25]许志琴,侯立玮,王宗秀.中国松潘-甘孜造山带的造山过程[M].北京:地质出版社,1992.
• [26]朱士飞,秦勇,钱壮志,等.云南省丽江-宾川地区二叠纪玄武岩地球化学特征及其构造背景研究[J].矿物岩石,2008,28(1):64-71.
• [27]姜常义,钱壮志,姜寒冰,等.云南宾川-永胜-丽江地区低钛玄武岩和苦橄岩的岩石成因与源区性质[J].岩石学报,2007,23(4):777-792.
• [28]朱弟成,潘桂堂,莫宣学,等.特提斯喜马拉雅二叠纪-白垩纪中-基性火山岩研究进展[J].地质科技情报,2003,22(2):26-37.
• [29]李红敬,解习农,颜佳新,等.扬子地区典型剖面二叠系不同沉积相地球化学特征[J].地质科技情报,2010,29(2):16-23.
• [30]Hawkesworth C J,Blake S,Evans P,et al.Time scales of crystal fraction in magmas chamber integrating physical isotopic and geochemical perspective[J].Journal of Petrology,2000,41(7):991-1006.
• [31]Hong D W,Zhang J S,Wang T,et al.Continental crustal growth and the supercontinental cycle:Evidence from the Central Asian Orogenic Belt[J].Asian Earth Sci.,2004,23(5):799-813.
• [32]肖龙,徐义刚,何斌.试论地幔柱构造与川滇西部古特提斯的演化[J].地质科技情报,2005,24(4):16-23.
• [33]Rollinson H R.Using gelchemical data:Evaluation,presentation,interpretation[M].[S.l.]:Longman Singapore Publishers Ltd.,1993.