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Chinese Science Bulletin 2001年第14期46卷 1203-1205页

作者： chen liang, sun yong, pei xianzhi, gao ming, feng tao, ZHANG zhongqing & chen Wen1. laboratory of continental dynamics, northwest university, xi’an 71.069, china 2. Department of Geology, northwest university, xi’an, 71.069, china 3. Institute of Geology, Chinese Academy of Geological Sciences, Beijing, 100037, china laboratory of {1. dynamics Northwest University Xi’an China Department of Geology Northwest University Xi’an China Institute of Geology Chinese Academy of Geological Sciences Beijing China

Whole rock 40Ar/39Ar age dating has been conducted on a basalt sample from Dur’ngoi ophiolite, Qinghai Province, which was reported to be the northernmost pa-leo-tethyan oceanic basin in Tibet. A high temperature pla-teau age (345.3±7.9 Ma) with an isochorn age (336.6±7.1.Ma) has been obtained, representing the eruption time of oceanic crust Considering related geological settings, the new age provides constraints on the northernmost pa-leo-tethyan suture zone in Tibet and the tectonic evolution of Paleo-tethys in Northeast Tibet and adjacent areas.

关键词： Dur’ngoi ophlolite 40Ar -39Ar age Paleo-tethys.

Comparison of eastern paleo-Tethyan ophiolites and its geodynamic significance--Evidence from Dur'ngoi ophiolite

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Science china Earth Sciences 2004年第4期47卷 378-384页

作者： chen liang1.2,{1.1.2, pei xianzhi2, feng tao2 & Zhang Guowei2 1. Open laboratory of continental dynamics, Ministry of Education, northwest university, xi抋n 71.069, china 2. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 1.0029, china Open laboratory of {1. dynamics Ministry of Education Northwest University Xi’an China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

Nd-Pb isotopic geochemistry of metabasalt from Dur抧goi ophiolite, Qinghai Prov-ince, NW china reveals the presence of DMM mixing with EMII components in its upper mantle source, which is comparable with present Indian MORB. Comparisons indicate that the geo-chemistry, chronology and source characteristics of Dur抧goi ophiolite coincide with Pa-leo-tethyan ophiolites from 揝anjiang?area. Together with evidences from regional geology in adjacent areas, this study proves that independent paleo-tethyan basins evolved contemporarily, the {1. of which is attributed to the interaction of mantle plume with over-riding lithosphere.

关键词： ophiolite, Paleo-Tethys, DUPAL anomaly, Indosinian movement.

Ultrahigh pressure (>7 GPa) gneissic K-feldspar (-bearing) garnet clinopyroxenite in the Altyn Tagh, NW china: Evi- dence from clinopyroxene exsolution in garnet

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Science china Earth Sciences 2005年第7期48卷 1000-1010页

作者： LIU liang1,3, chen Danling1, ZHANG Anda1, sun yong1, WANG Yan1, YANG Jiaxi1,2 & LUO Jinhai1 1. Key laboratory of continental dynamics of the Ministry of Education of china, northwest university, xi’an 71.069, china 2. College of Earth Science and Land Resources, Chang’an university, xi’an 710054, china 3. The laboratory of Orogen and Basin of the Ministry of Education, Peking university, Beijing 100871, china Key laboratory of {1. dynamics Ministry of Education of China Northwest University Xi'an 710069 China laboratory of Orogen and Basin Ministry of Education Peking University Beijing 100871 China College of Earth Science and Land Resources Chang'an University Xi'an 710054 China

The exsolution of clinopyroxene and rutile in coarse-grain garnet is found in the gneissic K-feldspar(-bearing) garnet clinopyroxenite from Yinggelisayi in the Altyn Tagh, NW china. The maximum content of the exsolved clinopyroxene in the garnet is up to >5% by volume. The reconstructed precursor garnet (Grt1. before exsolution has a maximum Si content of 3.061.per formula uint, being of supersilicic or majoritic garnet. The peak-stage metamorphic pressure of >7 GPa is estimated using the geobarometer for volume percentage of exsolved pyroxene in garnet and the Si-(Al+Cr) geobarometer for majoritic garnet, and the temperature of about 1.00℃ using the ternary alkali-feldspar geothermometer and the experimental data of ilmen- ite-magnetite solid solution. The protoliths of the rocks are intra-plate basic and intermediate ig- neous rocks, of which the geochemical features indicate that they are probably the products of the evolution of basic magma deriving from the {1. lithosphere mantle. The rocks are in outcrops associated with ultrahigh pressure garnet-bearing lherzolite and ultrahigh pressure garnet granitoid gneiss. All of these data suggest that the ultrahigh pressure metamorphic rocks in the Altyn Tagh are the products of deep-subduction of the {1. crust, and such deep- subduction probably reaches to >200 km in depth. This may provide new evidence for further discussion of the dynamic mechanism of the formation and evolvement of the Altyn Tagh and the other collision orogenic belts in western china.

关键词： Altyn Tagh gneissic K-feldspar (-bearing) garnet clinopyroxenite clinopyroxene exsolution in garnet ultra-high pressure metamorphism.

Sm-Nd and zircon SHRIMP U-Pb dating of Huilanshan mafic granulite in the Dabie Mountains and its zircon trace element geochemistry

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Science china Earth Sciences 2005年第12期48卷 2081-2091页

作者： HOU Zhenhui1, LI Shuguang1, chen Nengsong2, LI Qiuli1 & LIU xiaoming3.1. School of Earth and Space Sciences, university of Science and Technology of china, Hefei 230026, china 2. The Key laboratory of continental dynamics of the Ministry of Education, northwest university, xi’an 71.069, china 3. Faculty of Earth Sciences, china university of Geosciences, Wuhan 430074, china School of Earth and Space Sciences University of Science and Technology of China Hefei China The Key laboratory of {1. dynamics of the Ministry of Education Northwest University Xi’an China Faculty of Earth Sciences China University of Geosciences Wuhan China

The mafic granulites from Huilanshan are outcropped on the center of the Luotian dome in the northern Dabie Mountains. The Sm-Nd isochron defined by granulite-facies meta-morphic minerals (garnet + clinopyroxene + hypersthene) yields an age of 1.6 ± 1. Ma indicating the early Cretaceous granulite-facies metamorphism. The cathodoluminescence (CL) images of zircons from the granulite show clearly core-mantle-rim structures. The zircon cores are charac-terized by typical oscillatory zoning and highly HREE enriched patterns, which suggests their magma origin. Some zircon cores among them with little Pb loss give SHRIMP U-Pb ages rang-ing from 753 to 780 Ma, which suggests that the protolith of Huilanshan granulite is Neopro-terozoic mafic rocks. The zircon mantles usually cut across the oscillatory zone of the zircon cores have 3.1. times lower REE, Th, U, Y, Nb and Ta contents than the igneous zircon cores but have high common Pb contents. These characteristics suggest that they were formed by hydrothermal alteration of the igneous zircons. The part of zircon mantles with little Pb loss give a similar SHRIMP U-Pb age (71.―780 Ma) to the igneous zircon cores, which implies that the hydrothermal events occurred closely to the magmatic emplacement. In view of the strong early Cretaceous magmatism in the Luotian dome, consequently, the Huilanshan mafic granulite was formed by heating of the Neoproterozoic mafic rocks in mid-low crust, which caused the granu-lite-facies metamorphism underneath the Dabie Mountains. The similarity between the granulite metamorphic age (1.6 ± 1. Ma) defined by Sm-Nd isochron and K-Ar age of 1.3.1.7 Ma given by amphible from the gneiss in Luotian dome suggests a rapid uplifting of the Luotian dome, which may result in further exhumation of the ultrahigh pressure metamorphic rocks in the Dabie Mountains.

关键词： Dabie orogen, granulite, zircon U-Pb ages, Sm-Nd age.

～4.1.Ga xenocrystal zircon from Ordovician volcanic rocks in western part of North Qinling Orogenic Belt

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Chinese Science Bulletin 2007年第21期52卷 3002-3010页

作者： WANG Hongliang {1. sun yong LIU xiaoming xu XueYi chen JuanLu ZHANG Hong DIWU ChunRong State Key laboratory of {1. dynamics Northwest University Xi'an 710069 China xi'an Institute of Geology and Mineral Resource Xi'an 710054 China

High-precision U-Pb dating by in situ LA-ICP-MS yields an age of 4079±5 Ma for a xenocrystal zircon from Ordovician volcanics of the Caotangou Group in western part of the North Qinling Orogenic Belt. As a result, the North Qinling Orogenic Belt becomes one of a few localities in the world that contain Hadean age records (4276±6 Ma and 4404±8 Ma detrital zircons from Jack Hill of the Yilgarn craton, 401. Ma Acasta gneisses of the Wopmay Orogeny and Burang quartzite with detrital zircon of 41.3 Ma in Tibet). It is also the first report of the Hadean age in Phanerozoic volcanics. The finding of the 4.1.Ga xenocrystal zircon provides not only the geochronological record of the oldest crustal materials in china, but also the condition for further search for rocks for{1. in the region during the early time of the Earth’s evolution. Thirty-six zircon U-Pb dates from the Ordovician volcanic rocks are subgrouped into seven generations that represent different tectono-magmatic events in the North Qinling Orogenic Belt. Among them, two periods of 0.9-1.5 Ga and 0.4-0.5 Ga are consistent with Mesoproterozoic and Early Paleozoic orogenies, respectively.

关键词：火山石造山地带锆石地质学

Re-Os isotopic constraint to the age of in komatiites in the Neoarchean Guyang greenstone belt,North china Craton

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Re-Os isotopic constraint to the age of in komatiites in the...

饱水-失水循环劣化条件下泥岩层理裂隙演化特征

中国科学院地质与地球物理研究所第十届(201.年度)学术年会

作者： MA XuDong~(1.),GUO JingHui~1.chen liang~2 & CHU ZhuYin~1.1.State Key {1. of Litho spheric Evolution,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 1.0029,china 2 State Key {1. of continental dynamics,Department of Geology,northwest university,xi’an 71.069,china

The 2.5 Ga Guyang greenstone belt is a major lithological unit in the northwestern part of the North{1. *** have recently been identified to occur within the lower part of the meta-volcanic sedimentary sequence of the greenstone *** biggest komatiite near Guyang has been mapped out,which is 500 m long and 50 m wide lenticular ***-Os isotopic compositions of 9 samples were analyzed to date the *** Os contents are from 0.88 to 2.63 ppb,identical with typical komatiites, and slightly lower than the normal *** Os/Os ratios are from 0.1.1. to 0.1.97,which are lower enough to exclude the origin of Phanerozoic magma as widely developed in adjacent *** calculated Re depletion model ages(T) are from 1.46 to 2454 Ma,among them the oldest age of 2454 Ma gives the minimum evaluation for the formation age of the Guyang ***,the komatiites are a part of the Guyang greenstone belt,indicating high degree melting of mantle during～2.5 Ga crustal growth event.

关键词： komatiite Re-Os isotope Guyang greenstone belt Archean North china Craton

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中南大学学报（自然科学版） 2024年第6期55卷 2198-2207页

作者：屈文航贾鹏飞陈子浩李瑞珂王勇西北大学地质学系大陆动力学国家重点实验室陕西西安710069 中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室湖北武汉430071

为了研究饱水-失水循环劣化条件下膨胀性泥岩的裂隙演化特征,首先,对制备的圆柱体泥岩样品进行5次饱水-失水循环试验;然后,对原状样、1.和5次循环后的泥岩样品进行CT扫描;最后,结合图像分析技术对泥岩内部层理裂隙网络进行三维数字重构... 详细信息

为了研究饱水-失水循环劣化条件下膨胀性泥岩的裂隙演化特征,首先,对制备的圆柱体泥岩样品进行5次饱水-失水循环试验;然后,对原状样、1.和5次循环后的泥岩样品进行CT扫描;最后,结合图像分析技术对泥岩内部层理裂隙网络进行三维数字重构,对泥岩层理裂隙演化特征进行定性和定量分析。研究结果表明:重构的三维数字模型体积与真实泥岩样品体积相近,能够准确地表征样品体积特征和变化情况;随着饱水-失水循环次数增加,泥岩在不同部位上呈现出不同的发展趋势,即上部的裂隙增长速率较快,而下部的增长速率相对较慢;随着饱水-失水循环次数增加,裂隙总体积和连通裂隙体积不断增大,而独立裂隙的体积基本保持不变;随着饱水-失水循环次数增加,孔隙网络模型中各参量都呈增大趋势,裂隙的宽度和连通性都逐渐增大;在饱水-失水循环中,楔裂压力作用形成连通的层理主裂隙,失水收缩作用形成矩形裂隙网络。

关键词：泥岩层理裂隙饱水-失水循环显微CT扫描

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Trace element and Nd isotope analyses of apatite in granitoids and metamorphosed granitoids from the eastern Central Asian Orogenic Belt:Implications for petrogenesis and post-magmatic alteration

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Geoscience Frontiers 2023年第2期14卷 71-85页

作者： xin-Yu Long Jie Tang Wen-liang Xu {1.-Yang sun Jin-Peng Luan Shuai xiong xiao-ming Zhang College of Earth Sciences Jilin UniversityChangchun 130061China Key laboratory of Mineral Resources Evaluation in Northeast Asia Ministry of Natural Resources of ChinaChangchun 130061China State Key laboratory of {1. dynamics Department of GeologyNorthwest UniversityXi’an 710069China Key laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern UniversityShenyang 110819China State Key laboratory of Superhard Materials Jilin UniversityChangchun 130012China

We present in situ trace element and Nd isotopic data of apatites from metamorphosed and metasomatized(i.e.,altered)and unaltered granitoids in the Songnen and Jiamusi massifs in the eastern Central Asian Orogenic Belt,with the aim of fingerprinting granitoid petrogenesis,including both the magmatic and post-magmatic evolution *** from altered granitoids(AG)and unaltered granitoids(UG)are characterized by distinct textures and geochemical *** from AG have irregular rim overgrowths and complex internal textures,along with low contents of rare earth elements(REEs),suggesting the re-precipitation of apatite during epidote crystallization and/or leaching of REEs from apatite by metasomatic ***(t)values of the these apatites are decoupled from zircon eHf(t)values for most samples,which can be attributed to the higher mobility of Nd as compared to Sm in certain *** from UG are of igneous origin based on their homogeneous or concentric zoned textures and coupled Nd-Hf isotopic *** element variations in igneous apatite are controlled primarily by the geochemical composition of the parental melt,fractional crystallization of other REEbearing minerals,and changes in partition *** contents and Eu/Eu^(*) values of apatites from UG correlate with whole-rock Sr and SiO2 contents,highlighting the effects of plagioclase fractionation during magma *** from UG can be subdivided into four groups based on REE *** 1.apatites have REE patterns similar to the host granitoids,but are slightly enriched in middle REEs,reflecting the influence of the parental melt composition and REE *** 2 apatites exhibit strong light REE depletions,whereas Group 3 apatites are depleted in middle and heavy REEs,indicative of the crystallization of epidote-group minerals and hornblende before and/or during apatite crystallization,*** 4 apatites are depleted in heavy REEs,but e

关键词： Eastern CAOB Granitoid petrogenesis Apatite geochemistry Fluid-induced alteration Nd-Hf isotopic decoupling Crustal assimilation

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合肥盆地热演化特征

石油与天然气地质 2004年第6期25卷 644-649页

作者：陈刚赵重远李丕龙任战利李向平李宗亮西北大学地质学系中国石化胜利油田有限公司山东东营257022

通过 5口钻井 2 3个样品镜质体反射率 (Ro)数据的统计分析 ,运用镜质体反射率 -深度 (Ro-H)剖面斜率及其对应地温梯度的筛分对比方法 ,综合研究了合肥盆地中新生代的热演化特征。结果表明 ,盆地不同区块二叠系、下侏罗统和下白垩统的Ro... 详细信息

通过 5口钻井 2 3个样品镜质体反射率 (Ro)数据的统计分析 ,运用镜质体反射率 -深度 (Ro-H)剖面斜率及其对应地温梯度的筛分对比方法 ,综合研究了合肥盆地中新生代的热演化特征。结果表明 ,盆地不同区块二叠系、下侏罗统和下白垩统的Ro数值大小存在较大差异 ,介于 0 .82 %～ 2 .70 % ,但其相应的Ro-H剖面斜率均显著大于上白垩统和下第三系 ,表明上、下白垩统之间存在明显的间断。下白垩统的地温梯度分布在 70 .80～ 1.0 .90℃ /km ,相对稳定区接近 70 .80℃ /km ,表明早白垩世存在一次规模较大的区域性构造 -热事件。上白垩统和下第三系Ro集中分布在 0 .4 0 %～ 0 .74 % ,地温梯度为38.30℃ /km。晚第三纪以来 ,盆地整体抬升冷却 ,地温梯度降至现今的 2 7.5 0℃

关键词：合肥盆地镜质体反射率(Ro) 古地温场构造-热演化

Zircon U-Pb Age,Geochemical,and Sr-Nd-Pb-Hf Isotopic Constraints on the Time Frame and Origin of Early Cretaceous Mafic Dykes in the Wuling Mountain Gravity Lineament,South china

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Acta Geologica Sinica(English Edition) 2021年第2期95卷 419-438页

作者： chen xiaoqing LIU Shen {1. Caixia XU Jingyan ZHAO Huibo {1. Guangying Ian M.COULSON sun Jinggui FAN Yan College of Earth Sciences Jilin UniversityChangchun 130061China State Key laboratory of {1. dynamics and Department of Geology Northwest UniversityXi'an 710069China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Solid Earth Studies laboratory Department of GeologyUniversity of ReginaReginaSaskatchewan S4S 0A2Canada

In view of the importance of mafic dyke swarms and their contribution to current scientific problems relating to South china,herein,we present the findings of studies on twenty–five representative mafic dykes cropping out in Hunan Province and Guangxi Zhuang Autonomous Region,within the southern Wuling Mountain gravity lineament,*** results include new zircon LA-ICP-MS U-Pb age,whole rock geochemical,Sr-Nd-Pb isotopic,and zircon Hf isotopic data for these *** dykes formed between 1.1.5±1.2 and 1.1.6±1.1.Ma,and have typical doleritic *** fall into the alkaline and shoshonitic series,are enriched in light rare earth elements(LREE),some large ion lithophile elements(LILE;e.g.,Rb,Ba,and Sr),Th,U,and Pb,and are depleted in Nb,Ta,Hf,and ***,the dolerites have high initial 87 Sr/86 Sr ratios(0.7055–0.7057),negativeεNd(t)and zirconεHf(t)values(-1..8 to-1..9,-30.4 to-1..9),and relatively constant initial Pb isotopic ratios(that are EM1.like,1..77–1..94,1..4{1..47,and 36.84–36.92 for 206 Pb/204 Pb,207 Pb/204 Pb,and 208 Pb/204 Pb,respectively).These results indicate that the dykes were likely derived from magma generated through low-degree partial melting(1.0%–1.%)of an EM1.like garnet–lherzolite mantle *** parental magmas fractionated olivine,clinopyroxene,plagioclase,and Ti-bearing phases with negligible crustal contamination,during ascent and dyke *** possible models have been proposed to explain the origin of Mesozoic magmatism along the Wuling Mountain gravity *** we propose a reasonable model for the origin of these mafic dykes,involving the collision between the paleo-Pacific Plate and South china,which led to subsequent lithospheric extension and asthenosphere upwelling,resulting in partial melting the underlying mantle lithosphere in the Early Cretaceous,to form the parental magmas to the WMGL mafic dykes,as studied.

关键词： mafic dykes magmatic origin Early Cretaceous Wuling Mountain gravity lineament South china