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An integrated north–south paleo-Dadu-Anning River: New insights from bulk major and trace element analyses of the Xigeda Formation

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China Geology 2024年第1期7卷 91-103页

作者： Yong Zheng Hai-bing li jia-wei Pan Ping Wang Ya Lai Zheng Gong Key Laboratory of Deep-Earth Dynamics Institute of GeologyChinese Academy of Geological SciencesChina Geological SurveyMinistry of Natural ResourcesBeijing 100037China jiangsu Donghai Continental Deep Hole Crustal Activity National Observaion and Research Station Lianyungang 222300China Southern Marine Science and Engineering Guangdong Laboratory Guangzhou 511458China Geophysical Exploration Center China Earthquake AdministrationZhengzhou 450002China Institute of Geophysics China Earthquake AdministrationBeijing 100081China

The Xianshuihe-Anninghe fault extends SE–S and constitutes the southeastern margin of the Tibetan ***,the Dadu River which is associated with the fault does not flow following the path,but makes a 90ºturn within a distance of 1 km at Shimian,heading east,and joins the Yangtze River,finally flowing into the East China *** to the abrupt turn,a low and wide pass near the Daqiao reservoir at Mianning separates the N–S course of the Dadu River from the headwater of the Anning River which then flows south into the Yunnan Province along the Anninghe ***,many previous studies assumed southward flow of the paleo-Dadu River from the Shimian to the Anning ***,evidences for the capture of the integrated N–S paleo-Dadu-Anning River,its timing,and causes are still *** study explored the paleo-drainage pattern of the Dadu and Anning Rivers based on bulk mineral and geochemical analyses of the large quantities of fluvial/lacustrine sediments along the trunk of the Dadu and Anning *** with sands in the modern Dadu River,the Xigeda sediments also exhibit a granitoid affinity with the bulk major mineral compositions of quartz(>50%),anorthite(about 10%),orthoclase(about 5%),muscovite(about 5%),and clinochlore(about 4%).Correspondingly,bulk major elements show high SiO_(2),with all samples>60%,and some of them>70%,low TiO_(2)(≤0.75%),P_(2)O_(5)(≤0.55%),FeO*(≤5%),and relatively high CaO(1.02%–8.51%),Na_(2)O(1.60%–2.52%),and K_(2)O(2.17%–2.71%),with a uniform REE ***,synthesizing all these results indicate that these lacustrine sediments have similar material sources,which are mainly derived from its course in the Songpan-Ganzi flysch block,implying that the paleo-Dadu originally flowed southward into the Anning River and provided materials to the Xigeda ancient *** rearrangement of the paleo-Dadu River appears to be closely related to the locally focused uplift driven by strong activities of the Xians

关键词： Dadu River Anninghe fault River diversion Xigeda Formation Tectonic uplift Provenance Songpan-Ganzi flysch Ancient lake Xianshuihe-Xiaojiang fault system Tibetan Plateau

Plume-lithosphere interaction in the Comei Large Igneous Province: Evidence from two types of mafic dykes in Gyangze, south Tibet, China

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China Geology 2024年第1期7卷 80-90页

作者： Ya-ying Wang ling-sen Zeng li-e Gao li-long Yan ling-hao Zhao jia-hao Gao Ying-long Di Guang-xu li Yi-hong Tian Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China National Research Center for Geoanalysis Chinese Academy of Geological SciencesBeijing 100037China China Nonferrous Metals(Guilin)Geology and Mining Co. LtdGuilin 541004China

Two suites of mafic dykes,T1193-A and T1194-A,outcrop in Gyangze area,southeast *** are in the area of Comei liP and have indistinguishable field occurrences with two other dykes in Gyangze,T0902 dyke with 137.7±1.3 Ma zircon age and T0907 dyke with 142±1.4 Ma zircon age reported by Wang YY et al.(2016),indicating coeval formation *** all the four diabase dykes into consideration,two different types,OIB-type and weak enriched-type,can be ***“OIB-type”samples,including T1193-A and T0907 dykes,show OIB-like geochemical features and have initial Sr-Nd isotopic values similar with most mafic products in Comei Large Igneous Provinces(liP),suggesting that they represent melts directly generated from the Kerguelen mantle ***“weak enriched-type”samples,including T1194-A and T0902 dykes,have REEs and trace element patterns showing withinplate affinity but have obvious Nb-Ta-Ti negative *** show uniform lowerεNd(t)values(−6‒−2)and higher 87Sr/86Sr(t)values(0.706‒0.709)independent of their MgO variation,indicating one enriched mantle *** their closely spatial and temporal relationship with the widespread Comei liP magmatic products in Tethyan Himalaya,these“weak enriched-type”samples are consistent with mixing of melts from mantle plume and the above ancient Tethyan Himalaya subcontinental lithospheric mantle(SCLM)in different *** weak enriched mafic rocks in Comei liP form one special rock group and most likely suggest large scale hot mantle plume-continental lithosphere *** process may lead to strong modification of the Tethyan Himalaya lithosphere in the Early Cretaceous.

关键词： OIB type diabase Comei Large Igneous Province Weakly enriched diabase Plume-lithosphere interaction Nb-Ta-Ti negative anomaly Kerguelen plume geological survey engineering Tibet Plateau

Remote sensing and its applications using GNSS reflected signals:advances and prospects

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Satellite Navigation 2024年第1期5卷 10-51页

作者： Shuanggen Jin Adriano Camps Yan jia Feng Wang Manuel Martin-Neira Feixiong Huang Qingyun Yan Shuangcheng Zhang Zhongyu li Komi Edokossi Dongkai Yang Zhiyu Xiao Zhongmin Ma Weihua Bai Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai200030China School of Surveying and Land Information Engineering Henan Polytechnic UniversityJiaozuo454003China Department of Signal Theory and Communications Technical University of CataloniaBarcelona08034Spain Department of Surveying and Geoinformatics Nanjing University of Posts and TelecommunicationsNanjing210023China School of Electronics and Information Engineering Beihang UniversityBeijing100191China European Space Research and Technology Centre(ESTEC) European Space Agency2200-AGNoordwijkThe Netherlands National Space Science Center Chinese Academy of SciencesBeijing100190China School of Remote Sensing and Geomatics Engineering Nanjing University of Information Science and TechnologyNanjing210044China College of geological Engineering and Geomatics Chang’an UniversityXi’an710054China University of Electronic Science and Technology of China Chengdu611731China

The Global Navigation Satellite Systems(GNSS),including the US’s GPS,China’s BDS,the European Union’s Galileo,and Russia’s GLONASS,offer real-time,all-weather,any-time,anywhere and high precision observations by transmitting L band signals continuously,which have been widely used for positioning,navigation and *** the development of GNSS technology,it has been found that GNSS-reflected signals can be used to detect Earth’s surface characteristics together with other signals of *** this paper,the current status and latest advances are presented on Global Navigation Satellite System-Reflectometry(GNSS-R)in theory,methods,techniques and *** developments and progresses in GNSS-R instruments,theoretical modeling,and signal processing,ground and space-/air-borne experiments,parameters retrieval(*** speed,sea surface height,soil moisture,ice thickness),sea surface altimetry and applications in the atmosphere,oceans,land,vegetation,and cryosphere are given and reviewed in ***,the challenges in the GNSS-R development of each field are also ***,the future applications and prospects of GNSS-R are discussed,including multi-GNSS reflectometry,new GNSS-R receivers,GNSS-R missions,and emerging applications,such as mesoscale ocean eddies,ocean phytoplankton blooms,microplastics detection,target recognition,river flow,desert studies,natural hazards and landslides monitoring.

关键词： GNSS Reflectometry Remote sensing Environmental change

A new species of Leptocycas (Zamiaceae) from the Upper Triassic sediments of liaoning Province,China

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Journal of Systematics and Evolution 2010年第4期48卷 286-301页

作者： 1,2,3jian-Wei ZHANG 2jian-Xin YAO 1jia-Rui CHEN 1Cheng-Sen li 1(State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,chinese academy of sciences,beijing 100093,China) 2(State Key Laboratory of Stratigraphy and Paleontology,Institute of Geology,chinese academy of geological sciences,beijing 100037,China) 3(Graduate University,chinese academy of sciences,beijing 100049,China) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (State Key Laboratory of Stratigraphy and Paleontology Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China) (Graduate University Chinese Academy of Sciences Beijing 100049 China) *Correspondence: Cheng-Sen li *Correspondence: ?Author for correspondence. E-mail: lics@*** Tel.: 86-10-6283-6436 Fax: 86-10-6259-3385.

A new cycad,Leptocycas yangcaogouensis ***.,was found in sediments from the Late Triassic in western liaoning,*** pinnately compound leaves(Pseudoctenis type)are screwed in a crown on the stem *** leaflets are linear,with parallel veins and decurrent bases on the *** leaf bases are *** cataphylls intermix with the *** female cone is ovoid in *** characteristics of the new plant are more similar to those of Leptocycas gracilis,a Triassic cycad from North America,but the new species differs from *** in the size of its stem(7–8 vs.3–5 cm in diameter,respectively),leaves(length×width 100×16 vs.30×7 cm,respectively)and leaf density along the stem(4–6 vs.1–2 bases/1 cm length,respectively).Both *** and ***,having leaves of the Pseudoctenis type,show a closer relationship to the extant Dioon of *** present study provides evidence for the origin of the genus Dioon,which may have come from Leptocycas plants of the *** would be assumed that the extent cycads in Zamiaceae originate from the pteridosperms in the Late Paleozoic and have evolved through the stage of *** and *** in Late Triassic,and reaching the extant Dioon.

关键词： China Cycadales Leptocycas Upper Triassic Zamiaceae

Cretaceous integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science China Earth sciences 2024年第4期67卷 1229-1289页

作者： Dangpeng XI Guobiao li Shijun jiaNG Xin RAO Tian jiaNG Tianyang WANG Zuohuan QIN Yasu WANG jianzhong jia Muhammad KAMRAN Zhongye SHI Yuyang WU Panxi WANG lixin SUN Qinggao ZENG Xiaoqiao WAN State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesBeijing 100083China College of Oceanography Hohai UniversityNanjing 213200China Key Laboratory of Palaeobiology and Petroleum Stratigraphy Nanjing Institute of Geology and PaleontologyChinese Academy of SciencesNanjing 210008China State Key Laboratory of Tibetan Plateau Earth System Environmentand Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China China National Offshore Oil Corporation limited Beijing 100028China Shanghai Science and Technology Museum Shanghai 200120China Xizang Bureau of geological and Mineral Exploration and Development Lhasa 850000China Tianjin geological Survey Center of China geological Survey Tianjin 300170China

The Cretaceous Period is a vital time interval in deciphering the evolutionary history of the Neo-Tethys Ocean and the convergence of different plates and blocks across the Qinghai-Tibetan Plateau.A detailed stratigraphic framework and paleogeographic patterns are the basis for understanding the evolution of the Neo-Tethys Ocean and the formation of the QinghaiTibetan ***,the Cretaceous stratigraphy,biota,paleogeography,and major geological events in the Qinghai-Tibetan Plateau are analyzed to establish an integrative stratigraphic framework,reconstruct the paleogeography during the Cretaceous Period,and decode the history of the major geological *** Cretaceous rocks of the Qinghai-Tibetan Plateau and its surrounding area are predominantly marine deposits,with a small amount of interbedded marine-terrestrial and terrestrial *** Indus-Yarlung Tsangpo Suture Zone was responsible for the deposition of deep marine sediments dominated by ophiolite suites and radiolarian *** the south,the Tethys Himalayas and Indus Basin received marine sediments of varying depths and lithology;to the north,the Xigaze and Ladakh forearc basins are also filled with marine *** Lhasa Block,Karakorum Block,western Tarim Basin,and West Burma block consist of shallow marine,interbedded marine-terrestrial,and terrestrial *** Qiangtang Basin and other areas are dominated by terrestrial *** Cretaceous strata of the Qinghai-Tibetan Plateau and its surrounding areas are widely distributed and diversified,with abundant foraminifera,calcareous nannofossils,radiolarians,ammonites,bivalves,and *** the basis of integrated lithostratigraphic,biostratigraphic,geochronologic,and chemostratigraphic analyses,we proposed herein a comprehensive stratigraphic framework for the Cretaceous Period of the eastern *** analyzing the Cretaceous biota of different biogeographic zones from eastern Neo-Tethys and its surrounding a

关键词： Qinghai-Tibetan Plateau Tethys Cretaceous Stratigraphy Biota Paleogeography

Cymbella Agardh属(硅藻门Bacillariophyta)的一个新化石种的发现及其微细构造

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微体古生物学报 2003年第4期20卷 435-438页

作者：李家英魏乐军郑绵平中国地质科学院地质研究所北京100037 中国地质科学院矿产资源研究所

新化石种 Cymbella taicuonensis L i et Zheng ***.是在研究西藏西北部日土县台错古湖剖面沉积物中硅藻植物群时发现的 ,剖面沉积物中保存了非常丰富的硅藻化石 ,Cymbella taicuonensis就是这些硅藻化石中的一个新化石种。对标本采用... 详细信息

新化石种 Cymbella taicuonensis L i et Zheng ***.是在研究西藏西北部日土县台错古湖剖面沉积物中硅藻植物群时发现的 ,剖面沉积物中保存了非常丰富的硅藻化石 ,Cymbella taicuonensis就是这些硅藻化石中的一个新化石种。对标本采用光学镜 (L M)和扫描电镜 (SEM)观察和照相。

关键词：硅藻分类台错西藏

The principal characteristics of the lithosphere of China

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Geoscience Frontiers 2010年第1期1卷 45-56页

作者： tingdong li chinese academy of geological sciences Beijing 100037 China College of Earth sciences Jilin University Changchun Jilin 130026 China

The lithospheric structure of China and its adjacent area is very complex and is marked by several prominent characteristics. Firstly, China＇s continental crust is thick in the west but thins to the east, and thick in the south but thins to the north. Secondly, the continental crust of the Qinghai--Tibet Plateau has an average thickness of 60-65 km with a maximum thickness of 80 km, whereas in eastern China the average thickness is 30-35 km, with a minimum thickness of only 5 km in the center of the South China Sea. The average thickness of continental crust in China is 47.6 km, which greatly exceeds the global average thickness of 39.2 km. Thirdly, as with the crust, the lithosphere of China and its adja- cent areas shows a general pattern of thicker in the west and south, and thinner in the east and north. The lithosphere of the Qinghai--Tibet Plateau and northwestern China has an average thickness of 165 kin, with a maximum thickness of 180--200 km in the central and eastern parts of the Tarim Basin, Pamir, and Changdu areas. In contrast, the vast areas to the east of the Da Hinggan ling-Taihang-Wuling Mountains, including the marginal seas, are characterized by lithospheric thicknesses of only 50-85 kin. Fourthly, in western China the lithosphere and asthenosphere behave as a ＂layered structure＂, reflecting their dynamic background of plate collision and convergence. The lithosphere and asthenosphere in eastern China display a ＂block mosaic structure＂, where the lithosphere is thin and the asthenosphere is very thick, a pattern reflecting the consequences of crustal extension and an upsurge of asthenospheric materials. The latter is responsible for a huge low velocity anomaly at a depth of 85--250 km beneath East Asia and the western Pacific Ocean. Finally, in China there is an age structure of ＂older in the upper layers and younger in the lower layers＂ between both the upper and lower crusts and between the crust and the lithospheric mantle.

关键词： Crust lithosphere Asthenosphere China

辽河群富铁表壳岩系磁铁矿微量元素组成对古元古代铁矿成因的制约——以周家地区为例

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岩石学报 2024年第10期40卷 3103-3113页

作者：王伟李勇樊金虎马双贾督中国地质科学院地质研究所北京100037 辽宁省第五地质大队有限责任公司大石桥115110

铁矿石是工业发展不可缺少的矿产资源,多数铁矿石赋存于前寒武纪条带状铁建造(BIF)中。古元古代是苏必利尔型BIF形成的重要时期,但它们在华北克拉通并不发育。在胶-辽-吉构造带的辽河群中存在一系列形成于2.2~2.1Ga的富铁表壳岩系及具... 详细信息

铁矿石是工业发展不可缺少的矿产资源,多数铁矿石赋存于前寒武纪条带状铁建造(BIF)中。古元古代是苏必利尔型BIF形成的重要时期,但它们在华北克拉通并不发育。在胶-辽-吉构造带的辽河群中存在一系列形成于2.2~2.1Ga的富铁表壳岩系及具有经济价值的块状和层状铁矿石。揭示这些富铁岩石中磁铁矿的成因,并与苏必利尔型BIF进行对比,对探索华北元古宙铁矿找寻方向有重要意义。本文对辽宁周家地区辽河群中的块状和层状铁矿石、共生浸染状和脉状矿化变粒岩及弱矿化磁铁变粒岩开展的岩相学和磁铁矿微量元素研究表明,区域存在三类地球化学特征不同的磁铁矿。第一类磁铁矿来自块状矿石和浸染状矿化变粒岩,它们的Mg、Mn含量较高,Ti、V和Co含量低;第二类磁铁矿赋存于层状矿石和弱矿化磁铁变粒岩中,它们的Mg、Mn含量较低而Ti、V和Co含量稍高;第三类磁铁矿仅产出于脉状矿化变粒岩中,它们的Cr-Ni-V-Ti-Mn体系与前两类磁铁矿均不相同。元素含量及变化趋势的相似性表明,块状和层状矿石的形成分别是浸染状矿化变粒岩和弱矿化磁铁变粒岩中磁铁矿进一步生长富集的结果,而脉状矿化变粒岩中铁镁组分含量高是导致第三类磁铁矿具有最高Cr、Mn含量的主要因素。在Cr-Ni、Ti-Ni/Cr和V-Ti图解中,本文研究的磁铁矿多数具有低温热液成因的元素地球化学特征。弱矿化磁铁变粒岩中磁铁矿的Ti和Ni含量具负相关性,表明它们经历了由高温到低温条件的变化过程。虽然都是变质-热液作用的产物,但本文研究的辽河群三类磁铁矿与西澳古元古代Hamersley苏必利尔型BIF中的磁铁矿在元素组成上存在明显差异,表明它们的形成条件在温度、氧逸度和体系成分等方面与典型苏必利尔型BIF中的磁铁矿不同。

关键词：磁铁矿地球化学古元古代 BIF 辽河群

lithospheric Evolution and Geodynamic Process of the Qinghai-Tibet Plateau: An Inspiration from the Yadong-Golmud-Ejin Geoscience Transect

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Acta Geologica Sinica(English Edition) 1999年第2期73卷 173-180页

作者： li tingdong GAO Rui WU Gongjian chinese academy of geological sciences 26 Baiwanzhuang Rd. Beijing 100037

Abstract The Tibet Geoscience Transect (Yadong-Golmud-Ejin) has revealed the basic structures, tectonic evolution and geodynamic process of the lithosphere of the Qinghai-Tibet plateau. The evidence of northward thrusting of the Indian plate beneath the Himalayans on the southern margin and to southward compression of the Alxa block on the northern margin has been found. They were the driving forces causing the plateau uplift. The plateau is a continent resulting from amalgamation of eight terranes. These terranes are separated by sutures or large-scale faults, and different terranes have different lateral inhomogeneities and multi-layered lithospheric structures. At depths of about 20–30 km of the crust in the interior of the plateau there commonly exists a low-velocity layer. It is an uncoupled layer of the tectonic stress; above the layer, the upper crustal slices were thrust and overlapped each other and the rocks underwent brittle deformation, thus leading to shortening and thickening of the upper crust. Below the layer, the lateral change of the structure of the lower crust varies most greatly and ductile deformation occurs. The lower crust velocity of southern Tibet shows the reversed feature; whereas the lower crust velocity of northern Tibet increases and displays strong gradient variation and the character of the double Moho. On the whole, the Moho of the plateau is greatly undulatory. Although the crust of the Qinghai-Tibet Plateau has a great thickness, the lithosphere does not thicken markedly. The plateau is in a state of bi-directional compression. The unstable change of the Moho, the interaction between the crust and mantle and between the lithosphere and asthenosphere caused by the sinking of the lithospheric mantle and the strike slip and extension of the crust are the major dynamic factors for maintaining the present height and scope of the Qinghai-Tibet Plateau.

关键词： Qinghai-Tibet Plateau lithosphere geotransect continental dynamics