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1.
南极乔治王岛中——新生代岩浆岩Sr—Nd—Pb同位素组成及源区特征 总被引：7，自引：1，他引：7
对乔治王岛１１个火山岩和２个侵入岩样品做了Ｓｒ－Ｎｄ－Ｐｂ同位素分析，其中（８７Ｓｒ／８６Ｓｒ）ｉ＝０．７０３２６～０．７０３９２，εＮｄ＝３．０２～６．７２，２０６Ｐｂ／２０４Ｐｂ＝１７．７７６～１８．５１５，２０７Ｐｂ／２０４Ｐｂ＝１５．．５０６～１５．５７１，２０８Ｐｂ／２０４Ｐｂ＝３７．８６８～３８．３０８。根据以上同位素组成及其相互关系并结合岩石学和微量元素特征及火山岩中熔融包裹体成分，得出以下结论：（１）研究的乔治王岛岩浆岩起源于亏损地幔（ＤＭＭ）和地幔流体交代成因的富集地幔ＥＭＩ混合形成的源区；（２）该源区具有广义Ｄｕｐａｌ异常，它正是由于ＥＭＩ组份加入即通过流体交代作用而产生的；（３）流体主要是俯冲深海沉积物脱碳酸盐作用而释放出的富ＣＯ２流体。 相似文献
2.
南极罗斯岛及泰勒谷地区火山岩的地球化学特征及成因讨论 总被引：2，自引：0，他引：2
利用微量元素和Ｓｒ，Ｎｄ，Ｐｂ同位素资料，得出了南极罗斯岛及泰勒谷地区火山岩来自于上地幔，五个地区火山岩具有相同的源区。岩石具有大洋岛屿玄武岩（ＯＩＢ）的特征。来自地幔的火山喷发的岩浆未遭受地壳物质的混染作用。地幔源区是具有高μ（＝２０６Ｐｂ／２０４Ｐｂ）比值的地幔组分ＨＩＭＵ与亏损地幔组分ＤＭＭ混合作用的结果，其中以ＨＩＭＵ组分为主，原生岩浆由具ＨＩＭＵ组分特征的深部地幔柱与浅部的ＤＭＭ混合而成。 相似文献
3.
冀西北水泉沟正长岩杂岩体的成因 总被引：11，自引：5，他引：11
水泉沟碱性正长岩杂岩体侵入于太古宇桑干群变质岩中，岩体主要由碱性长石正长岩、角闪碱长正长岩、正长岩、石英碱长正长岩等组成，属碱性岩系列，在岩石的石英颗粒中见有熔融包体的存在。岩石的稀土元素分布模式呈平滑的右倾模式，无明显的铕异常。岩石的Ｐｂ同位素组成为２０６Ｐｂ／２０４Ｐｂ＝１６．４５７～１８．２８６、２０７Ｐｂ／２０４Ｐｂ＝１５．２７０～１５．４７２、２０８Ｐｂ／２０４Ｐｂ＝３６．５３９～３７．３９３，石英的δ１８Ｏ值为８．０‰～８．５‰，（８７Ｓｒ／８６Ｓｒ）ｉ≈０．７０５，岩石的ｔＤＭ为１．６～１．９Ｇａ，εＮｄ（ｔ）为－７．４５～－１３．１，明显大于区域基底的εＮｄ（ｔ）值（－２０±）。以上结果表明，岩体为上地幔和下地壳物质部分熔融的产物。岩体角闪石３９Ａｒ－４０Ａｒ年龄３２７Ｍａ，为海西期岩浆作用的产物 相似文献
4.
青藏高原岩石圈演化的记录：藏北超钾质及钠质火山岩的岩石学与地球化学特征 总被引：56，自引：12，他引：44
藏北鱼鳞山超钾质火山岩为一中等规模的熔岩被, 可分为三期。前两期主要为霞石黝方白榴石响岩、霞石白榴斑岩等, 后期主要为方钠石霓石粗面岩、霓霞粗面岩等。时代为１８～３０ Ｍａ。本区超钾质岩浆 Ｓｉ Ｏ２ 强烈不饱和、强碱性、高度富集 Ｌ Ｒ Ｅ Ｅ及 Ｌ Ｉ Ｌ Ｅ、放射成因 Ｓｒ、 Ｐｂ 及非放射成因 Ｎｄ 同位素 （８６ Ｓｒ／８７ Ｓｒ＝ ０７０８７６６～０７０９１６２, ２０６ Ｐｂ／２０４ Ｐｂ＝ １８８８２８８８～ １９１０４７５１, ２０７ Ｐｂ／２０４ Ｐｂ＝ １５６４２０３７ ～ １５８２８４５８, ２０８ Ｐｂ／２０４ Ｐｂ＝ ３９１３８９２１ ～ ３９６８６８３５ 及１４３ Ｎｄ／１４４ Ｎｄ＝ ０５１２１１６ ～０５１２３４２）,其上述特征指示岩浆源区为受到地壳物质强烈交代的富集 Ｅ Ｍ Ｉ Ｉ型地幔。藏北拉嘎拉钠质碱性橄榄玄武岩为高原面上的剥蚀残丘, 时代为６０ Ｍａ。其岩石学、 Ｒ Ｅ Ｅ、微量元素及 Ｓｒ Ｎｄ Ｐｂ 同位素指示了岩浆源区为受到洋壳俯冲物质交代的轻度富集地幔。本研究结果指示, 羌塘高原南部富集地幔的形成可能是受到印度板块俯冲的影响。 相似文献
5.
一个造山后的辉长岩—河南新县王母观岩体的地球化学特征 总被引：17，自引：1，他引：17
河南新县王母观辉长岩（２６１Ｍａ）侵位在定远组（３９１Ｍａ）中。岩体贫Ｋ、Ｚｒ、Ｙ、Ｔａ、Ｔｈ、Ｈｆ，ＬＲＥＥ略亏损，具明显的Ｅｕ正异常，εＮｄ（ｔ）较低（＋３－－１．０），εＳｒ（ｔ）低（－５－－８），δ＾１８Ｏ在地幔范围内（＋５．６‰－＋６．４‰）。Ｎｄ－Ｓｒ同位素关系暗示岩体源于大陆下略亏损的地幔源区，推测为亏损地幔端元（ＤＭＭ）与第一类富集地幔端元（ＥＭＩ）混合的产物。矿物、微量元素和同位 相似文献
6.
北秦岭晚古生代—中生代花岗岩类的Nd.Sr.Pb同位素地球化学特征及Nd.Sr 总被引：1，自引：0，他引：1
北秦岭晚古生代—晚中生代花岗岩类的Ｎｄ，Ｓｒ同位素研究表明：具低放射成因Ｐｂ同位素组成的花岗质岩基主要是南秦岭基底变质岩深熔的产物；而具高放射成因Ｐｂ同位素组成的原地、半原地型花岗岩类是北秦岭丹凤群有关岩石深熔和交代作用形成的产物．它们都可分为Ｉ型和Ｓ型，并可同时共存，岩浆源区中都有基性岩石物质的加入，其区别是基性岩类物质对Ｉ型花岗岩类的贡献分数较大，具有较小的亏损地幔模式年龄；由于岩浆源区中不同物质组成的混合，花岗岩类的亏损地幔模式年龄并不代表真实的壳幔分异事件的年龄．从新元古代到晚中生代，Ｉ型花岗岩类的ｄ（ｔ）和ＴＤＭ具逐渐变小的趋势，反映了地壳中基性岩石物质发生深熔作用的时间逐渐变晚，而Ｓ型花岗岩类的ｄ（ｔ）增大，ＴＤＭ变小，反映了基性岩石物质加入比例的增大，暗示着碰撞作用阶段具更加强烈的岩浆作用 相似文献
7.
天山托洋峰花岗质岩石的同位素地球化学特征 总被引：5，自引：0，他引：5
分析了西天山托木尔峰地区花岗质岩石和基底岩石的稀土元素,微量元素以及Ｏ、Ｐｂ、Ｓｒ、Ｎｄ同位素组成。本区北部伊犁地块基底岩石的Ｎｄ同位素模式年龄约为１．９Ｇａ,南部南天山褶皱带的约为０．７０５到０．７３３）表明本区花岗质岩石主要为地壳溶融产物。Ｏ、Ｐｂ、Ｓｒ、Ｎｄ同位素组成批示位于伊犁地块和南天山褶皱带的花岗岩源区岩石的Ｎｄ模式年龄都相当于伊犁地壳,但源区性质不同,前者源区δ＾１８Ｏ低,μ值低,Ｔ 相似文献
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9.
武当地块基性岩墙群及耀岭河群基性火山岩的Sr,Nd,Pb,O同位素研究 总被引：9，自引：2，他引：7
武当地块基性岩墙群与耀岭河群基性火山岩的Ｓｒ、Ｎｄ、Ｐｂ同位素特征反映它们具相同的混合地幔源区。前者的（＾８７Ｓｒ／＾８６Ｓｒ）ｉ＝０．６９０５￣０．７０６１,εＮｄ（ｔ）＝－１．９￣５．０,Δ＾２０８Ｐｂ／＾２０４Ｐｂ＝３５．４９￣１９０．２６,Δ＾２０７Ｐｂ／＾２０４Ｐｂ＝４￣８５,Ｔｈ／Ｔａ低,Ｌａ／Ｙｂ变化大;后者的（＾８７Ｓｒ／＾８６Ｓｒ）ｉ＝０．６４８７￣０．７０７５,εＮｄ（ｔ）＝０ 相似文献
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11.
Gilles Serge Odin 《Comptes Rendus Geoscience》2002,334(6):409-414
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414. 相似文献
12.
Inter-regional correlation of transgressions and regressions in the Cretaceous period 总被引：1，自引：0，他引：1
T. Matsumoto 《Cretaceous Research》1980,1(4):359-373
Well investigated platforms have been selected in each continent, and the history of Cretaceous transgressions and regressions there is concisely reviewed from the available evidence. The factual records have been summarized into a diagram and the timing of the events correlated between distant as well as adjoining areas.On a global scale, major transgressions were stepwise enlarged in space and time from the Neocomian, via Aptian-Albian, to the Late Cretaceous, and the post-Cretaceous regression was very remarkable. Minor cycles of transgression-regression were not always synchronous between different areas. Some of them were, however, nearly synchronous between the areas facing the same ocean.Tectono-eustasy may have been the main cause of the phenomena of transgression-regression, but certain kinds of other tectonic movements which affected even the so-called stable platforms were also responsible for the phenomena. The combined effects of various causes may have been unusual in the Cretaceous, since it was a period of global tectonic activity. The slowing down of this activity followed by readjustments may have been the cause of the global regression at the end of the Cretaceous. 相似文献
13.
The Afyon stratovolcano exhibits lamprophyric rocks, emplaced as hydrovolcanic products, aphanitic lava flows and dyke intrusions, during the final stages of volcanic activity. Most of the Afyon volcanics belong to the silica-saturated alkaline suite, as potassic trachyandesites and trachytes, while the products of the latest activity are lamproitic lamprophyres (jumillite, orendite, verite, fitztroyite) and alkaline lamprophyres (campto-sannaite, sannaite, hyalo-monchiquite, analcime–monchiquite). Afyon lamprophyres exhibit LILE and Zr enrichments, related to mantle metasomatism. 相似文献
14.
正20140751 Guo Xincheng(Geological Party,BGMRED of Xinjiang,Changji 831100,China);Zheng Yuzhuang Determination and Geological Significance of the Mesoarchean Craton in Western Kunlun Mountains,Xinjiang,China(Geological Review,ISSN0371-5736,CN11-1952/P,59(3),2013,p.401-412,8 相似文献
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正20141058 Chen Ling(Key Laboratory of Mathematical Geology of Sichuan Province,Chengdu University of Technology,Chengdu610059,China);Guo Ke Study of Geochemical Ore-Forming Anomaly Identification Based on the Theory of Blind Source Separation(Geosci- 相似文献
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正20141334 Chen Kun(Institute of Geophysics,China Earthquake Administration,Beijing100081,China);Yu Yanxiang Shakemap of Peak Ground Acceleration with Bias Correction for the Lushan,Sichuan Earthquake on April20,2013(Seismology and Geology,ISSN0253-4967,CN11-2192/P,35(3),2013,p.627-633,2 illus.,1 table,9 refs.)Key words:great earthquakes,Sichuan Province 相似文献
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正20141624 Cai Xiongfei(Key Laboratory of Geobiology and Environmental Geology,Ministry of Education,China University of Geosciences,Wuhan 430074,China);Yang Jie A Restudy of the Upper Sinian Zhengmuguan and Tuerkeng Formations in the Helan Mountains(Journal of Stratigraphy,ISSN0253-4959CN32-1187/P,37(3),2013,p.377-386,5 illus.,2 tables,10 refs.) 相似文献
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正20142263Lü Shaojun(Geological Survey of Jiangxi Province,Nanchang 330030,China)Early-Middle Permian Biostratigraphical Characteristics in Qiangduo Area,Tibet(Resources SurveyEnvironment,ISSN1671-4814,CN32-1640/N,34(4),2013,p.221-227,2illus.,2tables,22refs.)Key words:biostratigraphy,Lower Permian,Middle Permian,Tibet 相似文献
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正20142560Hu Hongxia(Regional Geological and Mineral Resources Survey of Jilin Province,Changchun 130022,China);Dai Lixia Application of GIS Map Projection Transformation in Geological Work(Jilin Geology,ISSN1001-2427,CN22-1099/P,32(4),2013,p.160-163,4illus.,2refs.) 相似文献
20.
正20140692 Duo Tianhui(No.402 Geological Team,Exploration of Geology and Mineral Resources of Sichuan Authority,Chengdu611730,China);Wang Yongli Computer Simulation of Neptunium Existing Forms in the Groundwater(Computing Techniques for Geophysical and Geochemical Exploration,ISSN1001-1749,CN51-1242/P,35(3), 相似文献