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| 1 | Remelting of subducted continental lithosphere: Petrogenesis of Mesozoic magmatic rocks in the Dabie-Sulu orogenic belt显示文摘The Dabie-Sulu orogenic belt was formed by the Triassic continental collision between the South China Block and the North China Block. There is a large area of Mesozoic magmatic rocks along this orogenic belt, with emplacement ages mainly at Late Triassic, Late Jurassic and Early Cretaceous. The Late Triassic alkaline rocks and the Late Jurassic granitoids only crop out in the eastern part of the Sulu orogen, whereas the Early Cretaceous magmatic rocks occur as massive granitoids, sporadic intermedi- ate-mafic intrusive and volcanic rocks throughout the Dabie-Sulu orogenic belt. Despite the different ages for their emplacement, the Mesozoic magmatic rocks are all characterized not only by enrichment of LREE and LILE but depletion of HFSE, but also by high initial Sr isotope ratios, low εNd(t) values and low radiogeneic Pb isotope compositions. Some zircons from the Jurassic and Cretaceous granitoids contain inherited magmatic cores with Neoprotozoic and Triassic U-Pb ages. Most of the Cretaceous mafic rocks have zircon δ18O values and whole-rock δ13C values lower than those for the normal mantle. A systematic comparison with adjacent UHP metaigneous rocks shows that the Mesozoic granitoids and mafic rocks have elemental and isotopic features similar to the UHP metagranite and metabasite, respectively. This indicates that these magmatic and metamorphic rocks share the diagnostic features of lithospheric source that has tectonic affinity to the northern edge of the South China Block. Their precursors underwent the UHP metamorphism and the post-collisional anatexis, respectively at different times and depths. Therefore, the Mesozoic magmatic rocks were derived from anatexis of the subducted continental lithosphere itself beneath the collision-thickened orogen; the geodynamic mechanism of the post-collisional magmatisms is tectonic collapse of orogenic roots in response to lithospheric extension. | ZHAO ZiFu ZHENG YongFei | 2009 | Science China Earth Sciences2009，52，9： | 60 |
| 2 | Chronology and geochemistry of metavolcanic rocks from Heigouxia Valley in the Mian-Lue tectonic zone, South Qinling——Evidence for a Paleozoic oceanic basin and its close time显示文摘The metavolcanic rocks of greenschist fades developed at Heigouxia Valley in the Mian-Lue tectonic zone, South Qinling orogenic belt is a bimodal volcanic series. It is composed of K-poor, Na-rich tholeiite and dacite-rhyolite. The trace elements characteristics with flat REE pattern of these tholeiites are similar to those of MORB. The Sm-Nd whole rock isochron age of(242±21) Ma and Rb-Sr whole rock isochron age of (221±13) Ma of this metavolcanic series consistently indicate their rnetamorphic time. Their relatively high initial εNd value of +6.1 at the rnetamorphic age (242 Ma) suggest that the volcanic rocks were derived from a depleted MORB type mantle source. Their trace elements and Nd isotope compositions suggest an oceanic basin developed from a rift on the continental margin of the Yangtze Block during the late Paleozoic and closed in the Triassic, This is the first case clearly showing the existence of relict of late Paleozoic oceanic crust in Fast Qinling belt, which provides important | 李曙光 孙卫东 张国伟 陈家义 杨永成 | 1996 | Science China Earth Sciences1996，39，3： | 59 |
| 3 | 奥陶纪-志留纪边界附近火山活动记录:来华南周缘钾质斑脱岩的信息显示文摘扬子地台内奥陶纪顶部的五峰组到志留纪底部的龙马溪组间存在着多个粘土岩层。前人研究结果认为这些粘土岩层为钾质斑脱岩,是火山喷发的凝灰质物质在海相环境沉积、蚀变的产物。这些斑脱岩广泛分布于扬子地台周缘,对理解奥陶纪-志留纪时华南所处的大地构造位置和相应的构造事件具有重要的意义。本文对采自扬子地台内湖北宜昌地区和贵州桐梓地区奥陶纪-志留纪界线剖面的斑脱岩层进行了矿物学及地球化学工作,旨在判定其形成的构造环境。矿物学研究表明上述岩石除了含有粘土矿物外,还含有石英、长石、黑云母、磷灰石、锆石等中酸性岩浆岩中的常见矿物,属典型的钾质斑脱岩。本文利用在风化过程中不活动元素对斑脱岩的原岩进行了恢复,结果也表明其原岩为中酸性火山岩,包括安山岩-英安岩-及流绞岩等。微量元素特征显示多数样品具有典型的岛弧火山岩的特征,很可能与北面早古生代秦岭洋的闭合过程中的板块俯冲有关,也可能是早古生代在华南板块东南缘外侧存在的一古老洋壳向华南板块的俯冲。有一个样品(YC0711)没有Nb的负异常,但是具有明显的Ti负异常,在Th/Yb-Nb/Yb判别图上落在岛弧区附近,其原岩可能是富铌玄武岩之类的特殊岛弧岩石。火山活动的峰期为晚奥陶世赫南特阶时代,与地质历史上第二大的生物大灭绝事件同时。前人认为该生物灭绝事件与冈瓦纳冰川有关。考虑到华南以及欧洲、北美等地均出现大规模晚奥陶世-早侏罗纪钾质斑脱岩,奥陶纪-志留纪边界的火山事件是具有全球规模的,所喷发的岩石多是富含挥发份的中酸性岩,对大气圈和生物圈具有十分重要的影响,本文认为火山活动很可能是造成晚奥陶世的生物大灭绝事件和冈瓦纳冰川的主要诱导因素。 | 胡艳华 孙卫东 丁兴 汪方跃 凌明星 刘健 | 2009 | 岩石学报2009，25，12： | 42 |
| 4 | Potash-rich volcanic rocks and lamprophyres in western Shandong Province:^(40)Ar-^(39)Ar dating and source tracing显示文摘Highly precise 40Ar-39Ar dating results demon-strate that the ages of potash-rich volcanic rocks in western Shandong Province are 114.7-124.3 Ma, and that of the lamprophyres is 119.6 Ma. The potash-rich volcanic rocks have relatively high (87Sr/86Sr)i ratios ( 0.708715-0.711418) and distinctly negative εNd values ( -11.47--17.54), and are enriched in radiogenic lead (206Pb/204Pb=17.341-17.622, 207Pb/204Pb=15.525-15.538, 208Pb/204Pb=37.563-37.684). Similarly, the lamprophyres also have quite low εNd values (-11.57 - -19.64). Based on the fact that the Sr, Nd and Pb isotopic compositions of potash-rich volcanic rocks are very consistent with that of the clinopyroxene separates, and by integrating comprehensive analyses of their tectonic settings, and extensive comparisons of the Sr, Nd isotopic composi-tions with that of the related simultaneous rocks, it is con-cluded that the potash-rich volcanic rocks and lamprophyres in western Shandong Province were most possibly derived from the partial melting | QIU Jiansheng, XU Xisheng & LO Ching-HuaState Key Laboratory of Mineral Deposit Research of Nanjing University, Nanjing 210093, China Department of Earth Sciences, Nanjing University, Nanjing 210093, China Department of Geology, Taiwan Unive | 2002 | Chinese Science Bulletin2002，47，2： | 39 |
| 5 | Geochemical and Pb-Sr-Nd isotopic compositions of Indosinian granitoids from the Bikou block,northwest of the Yangtze plate:Constraints on petrogenesis,nature of deep crust and geodynamics显示文摘This paper reports geochemical and Pb-Sr-Nd isotopic compositions of the Indosinian Yangba (215 Ma),Nanyili (225 Ma) and Mopi granitoids from the Bikou block of the northwestern margin of the Yangtze plate. These granitoids are enriched in Al (Al2O3:14.56%―16.48%) and Sr (352 μg/g―1047 μg/g),and depleted in Y (<16 μg/g) and HREE (e.g. Yb<1.61 μg/g),resulting in high Sr/Y (36.3―150) and (La/Yb)N (7.8―36.3) ratios and strongly fractionationed REE patterns. The Indosinian granotoids show initial Sr isotopic ratios (ISr) from 0.70419 to 70752,εNd(t) values from-3.1 to -8.5,and initial Pb isotopic ratios 206Pb/204Pb=17.891-18.250,207Pb/204Pb=15.494-15.575,and 208Pb/204Pb=37.788-38.335. Their geochemi-cal signatures indicate that the granitoids are adakitic. However,they are distinct from some adakites,generated by partial melting of subducted oceanic slab and/or underplated basaltic lower crust,be-cause they have high K (K2O: 1.49%―3.84%) and evolved Nd isotopic compositions,with older Nd iso-topic model ages (TDM=1.06―1.83 Ga). Geochemical and Sr-Nd isotopic compositions suggest that the magmas of the Insoninian adakitic rocks in the Bikou block were derived from partial melting of thick-ened basaltic lower crust. Combined with regional analyses,a lithospheric delamination model after collision between the North China and South China plates can account for the Indosinian adakitic magma generation. On the other hand,based on the Pb-Sr-Nd isotopic probing to the magma sources of the adakitic rocks,it is suggested that there is an unexposed continent-type basement under the exposed Bikou Group volcanic rocks. This can constrain on the Bikou Group volcanic rocks not to be MORB-or OIB-type. | ZHANG HongFei XIAO Long ZHANG Li YUAN HongLin JIN LanLan | 2007 | Science China Earth Sciences2007，50，7： | 38 |
| 6 | 江西井冈山地区早古生代沉积岩的地球化学特征及其对沉积环境的制约显示文摘本文研究的井冈山地区位于华夏地块中部,在早古生代寒武纪-奥陶纪时期沉积了巨厚的泥砂质韵律岩层夹碳酸盐岩和含碳岩层。它们具有较高的SiO_2(53.12%~86.37%,平均为70.16%)和Al_2O_3含量(5.43%~22.70%,平均为13.54%),高的Al_2O_3/(CaO+Na_2O)(1.36~174.6,平均为45.5)与K_2O/Na_2O比值(1.0~64.7,平均为20.4)以及低的TiO_2(0.30%~0.95%,平均为0.62%)和CaO含量(0.05%~6.05%,平均为0.63%)。它们具有与上地壳相似的微量元素和稀土元素组成,即富集大离子亲石元素和轻稀土元素,铕负异常明显。它们的主量元素、微量元素和稀土元素特征显示其沉积环境主要为被动大陆边缘浅海环境,物源区被剥蚀物质以上地壳成分为主。根据研究区内早古生代沉积物中没有蛇绿岩和火山岩、Ce异常较弱、有机碳的δ^(13)C_(org)值较低(-30.2‰~-25.4‰)、以及在沉积物中普遍发育的浅海沉积标志,如波痕、荷重模、泥砾、小型斜层理、含腕足类和腹足类等生物化石的灰岩透镜体等,认为研究区在早古生代时期不是洋盆,而是浅海-半深海或陆壳海槽,是由成冰纪时期的裂解事件,使原先的华南地块被肢解成许多次级块体(如武夷、赣中南、云开等)、各块体间成为浅海盆地的结果。 | 沈渭洲 舒良树 向磊 张芳荣 王博 | 2009 | 岩石学报2009，25，10： | 33 |
| 7 | 火山喷发活动对烃源岩的影响:以拉布达林盆地上库力组为例显示文摘本文以拉布达林盆地下白垩统上库力组火山岩系中发育的一套优质烃源岩为研究对象,应用岩石热解、氯仿沥青抽提、镜质体反射率分析、饱和烃气相色谱分析和色谱-质谱分析以及全岩成分分析等多种方法和手段,探讨火山喷发活动对烃源岩中有机质成熟度、烃源岩生烃特征及优质烃源岩形成的影响。研究结果表明:烃源岩的有机质镜质体反射率(R_0)在0.56%~0.62%之间,最大热解温度(T_(max))在429~442℃之间,部分样品的氯仿沥青'A'转化率(A/TOC)和烃转化率(HC/TOC)分别>5%和>3%。上述各种参数均指示有机质成熟度处于低成熟阶段,说明火山喷发活动对烃源岩有机质成熟度影响不明显。在火山喷发活动和烃源岩相互作用过程中,火山岩中过渡金属元素发生迁移,致使烃源岩中过渡金属元素含量增加。由于过渡金属元素对烃源岩生烃有催化作用,因此,火山喷发活动可以促进烃源岩早生烃,有利于低熟油的形成。火山喷发活动带来的热液一方面给湖盆水体中的水生生物带来了大量的营养物质,促进水生生物繁殖,为优质烃源岩的形成奠定了丰富的物质基础;另一方面,火山热液使水体含盐度增加,形成还原环境,为有机质的保存和转化提供了有利条件。 | 高福红 高红梅 赵磊 | 2009 | 岩石学报2009，25，10： | 34 |
| 8 | Shoshonitic intrusive suite in SE Guangxi: Petrology and geochemistry显示文摘A NE-direction Mesozoic shoshonitic intrusive s黫te in SE Guangxi has been identified in terms of geological, petrological and geochemical investigations. The shoshonitic intrusives are characterized by enrichment of LILE, HFSE and LREE and no obvious Nb-Ta depletion, similar to those potassic rocks formed in within-plate and rifting environments. Unlike most shoshonitic rocks forming in arc settings, the SE Guangxi shoshonitic intrusives were likely generated during regional lithosphere extension induced by upwelling of asthenosphere mantle. | LI Xianhua ZHOU Hanwen LIU Ying LEE Chi-yu SUN Min CHEN Chenhong | 2000 | Chinese Science Bulletin2000，45，7： | 32 |
| 9 | Geochronology of Ailaoshan-Jinshajiang alkali- rich intrusive rocks and their Sr and Nd isotopic characteristics显示文摘Twenty-nine isotopic ages, ranging from 41 to 27 Ma, are presented for the alkali-rich intrusive rocks and their coexisting alkaline volcanic rocks, lamprophyres and acidic porphyries, indicating that they are Tertiary in age. The alkali-rich intrusive rocks have 143Nd/144Nd ratios from 0. 512 415 to 0. 512 544, and 87Sr/86Sr ratios from 0.705 4 to 0.706 8, suggesting that their material originates from an enriched mantle source. | 张玉泉 谢应雯 | 1997 | Science China Earth Sciences1997，40，5： | 29 |
| 10 | 华北克拉通东北缘岩石圈深部物质组成的不均一性:来自吉林南部中生代火山岩元素及Sr-Nd同位素地球化学的证据显示文摘本文报导了吉林南部果松组和三棵榆树组火山岩的全岩K-Ar和角闪石^(40)Ar/^(39)Ar定年结果和岩石地球化学资料,并讨论了吉林南部早白垩世火山岩岩浆源区性质以及空间变异。定年结果显示,果松组和三棵榆树纽火山岩的形成时代分别为130.2±0.3Ma和118.3±1.9Ma。果松组火山岩主要由玄武岩-玄武质粗面安山岩-粗面安山岩-英安岩组成;它们的SiO_2含量介于46%~64%,Mg~#介于31~50之间,Al_2O_3含量介于14.9%~18.9%之间,全碱含量(Na_2O+K_2O)介于4.61%~9.23%之间,属于亚碱性系列,具钙碱性演化趋势;并以富集大离子亲石元素(LILEs)和轻稀土元素(LREEs),亏损重稀土元素(HREEs)和Nb、Ta、Ti等高场强元素(HFSEs)为特征;(^(87)Sr/^(86)Sr)_i值和ε_(Nd)(t)值分别介于0.7065~0.7077和-2.67~ -19.71之间。果松组火山岩的成分具有较好的空间变异趋势,由东向西,火山岩的基性程度增高,东部果松组火山岩具有较高的(^(87)Sr/^(86)Sr)。值,而西部具有较低的ε_(Nd)(t)值。三棵榆树组火山岩由粗面安山岩和粗面英安岩组成;三棵榆树组火山岩的SiO_2含量介于55.5%~65.8%之间,Mg~#介于42~50,Al_2O_3含量介于15.0%~15.7%,全碱含量偏高(Na_2O+K_2O=6.93%~9.24%),主体属于亚碱性系列,具钙碱性系列的演化趋势;并以较高的Th/U(5.36~5.82)、Ba/Nh(50.2~120.0)、(La/Yh)_N(32.9~47.9)和Sr/Y(50.0~72.4)比值为特征;它们的(^(87)Sr/^(86)Sr)_i值和ε_(Nd)(t)值分别变化于0.7056~0.7057和-8.99~-19.71之间。上述特征揭示,果松组火山岩(130Ma)的形成主要与古太平洋板块的俯冲作用有关,岩浆来源于受流体/熔体交代的地幔楔,东西部受到不同程度陆壳物质的混染。与果松组火山岩相比,三棵榆树组火山岩(118Ma)形成于俯冲背景下的相对引张环境,岩浆来源于受交代的岩石圈地幔,但受到深部陆壳物质的混染。 | 裴福萍 许文良 杨德彬 于洋 孟恩 | 2009 | 岩石学报2009，25，8： | 28 |
| 11 | Chronology of ultrahigh-pressure metamorphism in the Dabie Mountains and Su-Lu terrane: I. Sm-Nd isotope system显示文摘If the protolith of coesite-bearing eclogite was gabbro, it could undergo ultrahigh-pressure metamorphism under dry condition. In this case, the Hocking temperatures of those minerals could be higher, so that Nd isotope disequilibrium between minerals could be observed. If the protolith of coesite-bearing edogite was metabasalt, amphiboles in the metabasalt were decomposed during ultrahigh-pressure metamorphism and released water. Thus Nd isotope compositions between the minerals were in equilibrium because the blocking temperatures of those minerals could he lower. The secondary alteration and fluid-rock interaction in high-pressure are major problems for Sm-Nd dating of eclogite. The reliable Sm-Nd isotopic ages of coesite-bearing eclogite from the Dabie Mountains and Su-Lu terrane range from 221 to 232 Ma. They are slightly lower, but very close to the peak metamorphic ages of the eclogites. The cold eclogite from the Sujiahe complex could be oceanic subduction origin in the Paleozoic. | 李曙光 肖益林 葛宁洁 陈移之 Emil Jagoutz | 1996 | Science China Earth Sciences1996，39，6： | 27 |
| 12 | Adakite-type sodium-rich rocks in Awulale Mountain of west Tianshan:Significance for the vertical growth of continental crust显示文摘The sodium-rich dacites and albite porphyries of Permian in the Awulale Mountain of west Tianshan have unique chemical and trace element signatures identical to adakite. These intermediate-acidic igneous rocks are characterized by high Na2O, Al2O3 and Sr contents and high Sr/Y and La/Y ratios (>40 and >20, respectively), and low Y and Yb contents, and strong depletion in HREE, and positive Eu anomaly. The (143Nd/144Nd)i is in the range from0.51236 to 0.51248 and the εNd(t) is positive value (+0.79-+3.11); the (87Sr/86Sr)i is in the range from 0.7052 to 0.7054. These Nd and Sr isotopic composition features indicate that the source rocks of these adakite-type rocks are from a weakly depleted mantle, or a depleted mantle, but was contaminated by the crustal materials. These adakite-type rocks were most likely derived from the partial melting of new underplated basaltic rocks under the conditions of amphibo-lite to eclogite transition in the postcollisional environment of North Xinjiang during the Permian | XIONG Xiaolin ZHAO Zhenhua BAI Zhenghua MEI Houjun WANG Yixian WANG Qiang XU Jifeng Niu Hecai BAO Zhiwei | 2001 | Chinese Science Bulletin2001，46，10： | 25 |
| 13 | 桐柏地区高压变质地体在地壳中的抬升机制显示文摘桐柏杂岩位于秦岭与大别造山带之间,南北两侧为NWW-SEE向延伸的含榴辉岩高压变质地体,其构造就位过程及其与高压变质地体的构造关系为地质学家们所关注。本文研究表明,所谓的桐柏杂岩实际上是一个早白垩世花岗质片麻岩杂岩体,其内包裹一定数量的三叠纪中高级变质岩石。桐柏杂岩南北两条边界韧性剪切带具有相反的运动学指向,分别为大型右行和左行韧性剪切带,其形成时代为131Ma。这两条韧性剪切带中的剪切面理分别朝SSW和NNE向倾斜,韧性剪切带及杂岩体内部发育的拉伸线理均稳定地朝SEE方向缓倾伏。而在杂岩体的东端发育低角度近南北向韧性剪切变形带,其糜棱面理朝SEE方向低角度缓倾斜,矿物拉伸线理也朝SEE方向低角度缓倾伏,运动学标志指示东侧地质体朝295°~310°的方向逆冲。因此,桐柏杂岩实际上被一个顺造山带的韧性剪切带所围限,这个韧性剪切带及杂岩体内部韧性变形运动学指示了一个早白垩世由东向西的低角度抬升过程,而这一过程直接导致了含榴辉岩高压变质地体沿着造山带的方向从地壳深部抬升到近地表。这一研究结果对理解和认识桐柏-大别-苏鲁地区高压-超高压变质地体的晚期抬升过程具有重要意义。 | 崔建军 胡健民 刘晓春 | 2009 | 岩石学报2009，25，9： | 21 |
| 14 | Chronology and geochemistry of the volcanic rocks in Woruo Mountain region,Northern Qiangtang depression:Implications to the Late Triassic volcanic-sedimentary events显示文摘A suite of sedimentary-volcaniclastic rocks intercalated with the volcanic rocks unconformably overlies the Triassic Xiaochaka Formation in the Woruo Mountain region, Qiangtang Basin, northern Tibet. The vitric tuff from the base of these strata gives a SHRIMP zircon U-Pb age of 216 ± 4.5 Ma, which represents the age of the Late Triassic volcanic-sedimentary events in the Woruo Mountain region, and is consistent with that of the formation of the volcanic rocks from the Nadi Kangri Formation in the Nadigangri-Shishui River zone. There is a striking similarity in geochemical signatures of the volcanic rocks from the Woruo Mountain region and its adjacent Nadigangri-Shishui River zone, indicating that all the volcanic rocks from the Qiangtang region might have the same magmatic source and similar tectonic setting during the Late Triassic. The proper recognition of the Late Triassic large-scale volcanic eruption and volcanic-sedimentary events has important implications for the interpretation of the Late Triassic biotic extinction, climatic changes and regressive events in the eastern Tethyan domain, as well as the understanding of the initiation and nature, and sedimentary features of the Qiangtang Basin during the Late Triassic-Jurassic. | WANG Jian FU XiuGen CHEN WenXi WANG ZhengJiang TAN FuWen CHEN Ming ZHUO JieWen | 2008 | Science China Earth Sciences2008，51，2： | 21 |
| 15 | A statistical model for porous structure of rocks显示文摘The geometric features and the distribution properties of pores in rocks were in- vestigated by means of CT scanning tests of sandstones. The centroidal coordi- nates of pores, the statistic characterristics of pore distance, quantity, size and their probability density functions were formulated in this paper. The Monte Carlo method and the random number generating algorithm were employed to generate two series of random numbers with the desired statistic characteristics and prob- ability density functions upon which the random distribution of pore position, dis- tance and quantity were determined. A three-dimensional porous structural model of sandstone was constructed based on the FLAC3D program and the information of the pore position and distribution that the series of random numbers defined. On the basis of modelling, the Brazil split tests of rock discs were carried out to ex- amine the stress distribution, the pattern of element failure and the inosculation of failed elements. The simulation indicated that the proposed model was consistent with the realistic porous structure of rock in terms of their statistic properties of pores and geometric similarity. The built-up model disclosed the influence of pores on the stress distribution, failure mode of material elements and the inosculation of failed elements. | JU Yang1,2, YANG YongMing1, SONG ZhenDuo3 & XU WenJing4 1 State Key Laboratory of Coal Resources and Safe Mining, China University of Mining & Technology, Beijing 100083, China 2 Department of Mechanical and Manufacturing Engineering, The University of Calgary, 2500 University Drive NW Calgary, AB T2N 1N4, Canada 3 China National Coal Mining Equipment Co. Ltd, Beijing 100011, China 4 Department of Materials and Metallurgy, The University of Utah, Salt Lake City, Utah 84112, USA | 2008 | Science China(Technological Sciences)2008，51，11： | 21 |
| 16 | Discovery and occurrence of high-pressure metapelitic rocks from Altun Mountain Areas, Xinjiang Autonomous Region显示文摘The Altun tectonic zone is an important left-handed strike-slip fault zone on the Asian continent. Recent studies reveal that the left-handed strike slip of this fault zone was developed not only in the Cenozoic, but also during the Late Ordovician. The fault zone is mainly composed of Proterozoic schists, volcanics, quartzites and carbonate rocks bearing stromatolites. The overlying strata are dominated by plateform carbonate rocks and | 车自成 刘良 刘洪福 罗金海 | 1995 | Chinese Science Bulletin1995，40，23： | 20 |
| 17 | Interaction between subducted continental crust and the mantle --Ⅱ. Sr and Nd isotopic geochemistry of the syncollisional mafic-ultramafic intrusions in Dabie Mountains显示文摘The syncollisional mafic\|ultramafic rocks with Nb, Zr, Ti negative anomalies in the North Dabie terrane have Sr and Nd isotopic compositions with EMI features. Their low and variable initial ε Nd values ranging from -2 to -18 are similar to those of their gneissic country rocks and the ultrahigh\|pressure metamorphic rocks in the South Dabie terrane. These Sr and Nd isotopic features are difficult to be interpreted by mantle metasomatism related to oceanic subduction or crust assimilation, but is best explained by the mantle metasomatism related to continental subduction. | 李曙光 聂永红 S.R.Hart 张宗清 | 1998 | Science China Earth Sciences1998，41，6： | 19 |
| 18 | 扬子地块北缘西乡群孙家河组火山岩形成时代及元素地球化学研究显示文摘西乡群孙家河组为一套低绿片岩相浅变质火山-沉积岩系,主要由基性-中基性-酸性火山岩和凝灰岩、沉凝灰岩、泥岩、硅质岩组成,火山岩岩石类型包括玄武岩、安山岩、英安岩和流纹岩。LA-ICPMS锆石U-Pb定年揭示流纹岩形成时代为832.9±4.9Ma,辉石玄武岩的形成时代为845.0±17Ma,两者在误差范围内一致,属新元古代同期岩浆作用产物。元素地球化学研究表明,孙家河组玄武岩属拉斑玄武岩系列,具有受地壳混染的板内玄武岩的地球化学特点。玄武岩-安山岩-英安岩主量元素成分投点呈规律性变化、REE球粒陨石标准化及微量元素原始地幔标准化分配型式具有一致性并相互重叠,不相容元素Th和相容元素Cr相关模拟图中沿分离结晶线分布,证明玄武岩-安山岩-英安岩为同一基性岩浆分离结晶的产物。REE和微量元素分配型式以及微量元素比值时的显著差异,暗示流纹岩与玄武岩-安山岩-英安岩来源于不同源区。Sr-Nd同位素研究表明,玄武岩-安山岩-英安岩样品的ε_(Nd)(t)值均大于0以及在ε_(Nd)(t)-(^(87)Sr/^(86)Sr),图解中位于OIB成分区,表明其源区应为与洋岛玄武岩类似的地幔源区;流纹岩样品具有可与基性熔岩相比拟的ε_(Nd)(t)值,暗示流纹岩最有可能是初生玄武质地壳部分熔融而成。本文所研究的原划孙家河组火山岩系列的形成时代、构造环境的确定以及扬子陆块乃至世界上同一时间内普遍发育大陆裂谷岩浆岩组合的地质事实,说明原划孙家河组以及西乡群中的确存在新元古代的组成部分,它们应是新元古代大陆裂谷的产物,它和扬子地块820Ma后造山裂解环境花岗岩均是新元古代晚期Rodinia超大陆裂解作用的岩浆响应。 | 徐学义 夏林圻 陈隽璐 马中平 李向民 夏祖春 王洪亮 | 2009 | 岩石学报2009，25，12： | 18 |
| 19 | 辽西北票蓝旗组火山岩锆石U-Pb年龄和Hf同位素组成显示文摘辽西北票常河营子地区有中生代蓝旗组火山岩分布,其中上部安山质角砾熔岩的锆石LA-ICPMS U-Pb年龄分析结果表明,其结晶年龄为159.4±3.4Ma,属晚侏罗世。锆石^(176)Hf/^(177)Hf比值介于0.282098~0.282789之间,ε_(Hf)(t)值为-20.4~+4.1,主体分布在华北克拉通地壳演化线之上,位于古元古代地壳演化范围内,所给出的亏损地幔年龄(t_(DM))和平均地壳模式年龄(t_(cruat))分别为0.7~1.6Ga和0.9~2.5Ga。结合已发表蓝旗组中酸性火山岩的岩石地球化学及Sr-Nd同位素组成特征,我们认为安山质火山岩源于古老(如晚太古代)下地壳玄武质岩石的部分熔融,其形成过程可能与中生代幔源岩浆底侵作用有关。 | 马强 郑建平 | 2009 | 岩石学报2009，25，12： | 16 |
| 20 | The geothermal formation mechanism in the Gonghe Basin: Discussion and analysis from the geological background显示文摘The Gonghe Basin,a Cenozoic down-warped basin,is located in the northeastern part of the Qinghai-Xizang (Tibetan) Plateau,and spread over important nodes of the transfer of multiple blocks in the central orogenic belt in the NWW direction.It is also called “Qin Kun Fork” and “Gonghe Gap”.The basin has a high heat flow value and obvious thermal anomaly.The geothermal resources are mainly hot dry rock and underground hot water.In recent years,the mechanism of geothermal formation within the basin has been controversial.On the basis of understanding the knowledge of predecessors,this paper proposes the geothermal formation mechanism of the “heat source–heat transfer–heat reservoir and caprock–thermal system”of the Gonghe Basin from the perspective of a geological background through data integrationintegrated research-expert,discussion-graph,compilation-field verification and other processes: (1) Heat source: geophysical exploration and radioisotope calculations show that the heat source of heat in the basin has both the contribution of mantle and the participation of the earth's crust,but mainly the contribution of the deep mantle.(2) Heat transfer: The petrological properties of the basin and the exposed structure position of the surface hot springs show that one transfer mode is the material of the mantle source upwells and invades from the bottom,directly injecting heat;the other is that the deep fault conducts the deep heat of the basin to the middle and lower parts of the earth's crust,then the secondary fracture transfers the heat to the shallow part.(3) Heat reservoir and caprock: First,the convective strip-shaped heat reservoir exposed by the hot springs on the peripheral fault zone of the basin;second,the underlying hot dry rock layered heat reservoir and the upper new generation heat reservoir and caprock in the basin revealed by drilling data.(4) Thermal system: Based on the characteristics of the “heat source-heat transfer-heat reservoir and caprock”,it is preliminarily believed that the Gonghe Basin belongs to the non-magmatic heat source hydrothermal geothermal system (type II21) and the dry heat geothermal system (type II22).Its favorable structural position and special geological evolutionary history have given birth to a unique environment for the formation of the geothermal system.There may be a cumulative effect of heat accumulation in the eastern part of the basin,which is expected to become a favorable exploration area for hot dry rocks. | Yan-fang Feng Xiao-xu Zhang Bo Zhang Jiang-tao Liu Yang-gang Wang De-long Jia Li-rong Hao Zhao-yu Kong | 2018 | China Geology2018，1，3： | 15 |
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