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Peri-Gondwanan terranes in the romanian Carpathians:A review of their spatial distribution,origin,provenance,and evolution

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Geoscience frontiers 2014年第3期5卷 395-411页

作者： Ioan Balintoni Constantin Balica Mihai N.Ducea Horst-Peter Hann Department of Geology Babes-Bolyai University400084 Cluj-NapocaRomania Department of Geosciences The University of Arizona1040 E.4th StreetTucsonAZ 85721USA faculty of Geology and Geophysics Bucharest UniversityStr.N.Balcescu Nr 1BucurestiRomania institut fr geowissenschaften Universitt Tbingen72076 TbingenGermany

The basement of the romanian Carpathians is made of Neoproterozoic to early Paleozoic peri- Gondwanan terranes variably involved in the Variscan orogeny, similarly to other basement terrains of Europe. They were hardly dismembered during the Alpine orogeny and traditionally have their own names in the three Carpathian areas. The Danubian domain of the South Carpathians comprises the Dragsan and Lainici-Paiius peri-Amazonian terranes. The Dragsan terrane originated within the ocean surrounding rodinia and docked with rodinia at -800 Ma. It does not contain Cadomian magmatism and consequently it is classified as an Avalonian extra-Cadomian terrane, The Lainici-Pfiius terrane is a Ganderian fragment strongly modified by Cadomian subduction-related magmatism, It is attached to the Moesia platform. The TisoviD terrane is an ophiolite that marks the boundary between Drfagsan and Lainici-Paius terranes. The other basement terranes of the romanian Carpathians originated close to the Ordovician North- African orogen, as a result of the eastern rheic Ocean opening and closure. Except for the Sebes-Lotru terrane that includes a lower metamorphic unit of Cadomian age, all the other terranes （Bretila, Tulghes, Negrisoara and rebra in the East Carpathians, Somes, Biharia and Baia de Aries in the Apuseni mountains, fagaras, Leaota, Carat and Pades in the South Carpathians） represent late Cambrian-Ordovician rock assemblages. Their provenance, is probably within paleo-nortbeast Africa, close to the Arabian-Nubian shield. The late Cambrian-Ordovician terranes are defined here as Carpathian-type terranes. According to their lithostratigraphy and origin, some are of continental margin magmatic arc setting, whereas others formed in rift and back-arc environment and closed to passive continental margin settings. In a paleo- geographic reconstruction, the continental margin magmatic arc terranes were first that drifted out, followed by the passive continental margin terranes with the b

关键词： romanian Carpathians pre-Alpine terranes U-Pb Geochronology Avalonian-type and Carpathian-type terranes Tornquist rheic and Paleotethyan sutures Ordovician North-African orogen

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Application of the three-dimensional telegraph equation to cosmic-ray transport

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research in Astronomy and Astrophysics 2016年第10期16卷 107-115页

作者： robert C. Tautz Ian Lerche Zentrum fur Astronomie und Astrophysik Technische Universitat Berlin HardenbergstraBe 36 D-10623 Berlin Germany institut fur geowissenschaften Naturwissenschaftliche Fakultat Ⅲ Martin-Luther-Universitat Halle D-06099 HalleGermany

An analytical solution to the three-dimensional telegraph equation is presented. This equation has recently received some attention but so far the treatment has been one-dimensional. By using the structural similarity to the Klein-Gordon equation, the telegraph equation can be solved in closed form. Illustrative examples are used to discuss the qualitative differences from the diffusion solution. A comparison with a numerical test-particle simulation reveals that some features of an intensity profile can be better explained using the telegraph approach.

关键词： plasmas -- turbulence -- magnetic field -- diffusion -- solar wind

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Deciphering the Origin of Abiotic Organic Compounds on Earth:review and future Prospects

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Acta Geologica Sinica(English Edition) 2023年第1期97卷 288-308页

作者： WANG Chao TAO renbiao Jesse B.WALTErS rEN Tianshi NAN Jingbo ZHANG Lifei MOE Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking UniversityBeijing 100871China Center for High Pressure Science and Technology Advanced research(HPSTAr) Beijing 100094China institut für geowissenschaften Goethe-Universität FrankfurtFrankfurt am Main 60438Germany Department of Ocean Science and Engineering Southern University of Science and TechnologyShenzhen 518055China

The geologic production of abiotic organic compounds has been the subject of increasing scientific attention due to their use in the global carbon flux balance,by chemosynthetic biological communities,and for energy *** analysis of methane(CH_(4))and other organics in diverse geologic settings,combined with thermodynamic modelings and laboratory simulations,have yielded insights into the distribution of specific abiotic organic molecules on Earth and the favorable conditions and pathways under which they *** updated and comprehensive review summarizes published results of petrological,thermodynamic,and experimental investigations of possible pathways for the formation of particular species of abiotic simple hydrocarbon molecules such as CH_(4),and of complex hydrocarbon systems,e.g.,long-chain hydrocarbons and even solid carbonaceous matters,in various geologic processes,distinguished into three classes:(1)pre-to early planetary processes;(2)mantle and magmatic processes;and(3)the gas/water-rock reaction processes in low-pressure ultramafic rock and high-pressure subduction zone *** not only emphasize how organics are abiotically synthesized but also explore the role or changes of organics in evolutionary geological environments after synthesis,such as phase transitions or organic-mineral ***,there is an urgent need to explore the diversity of abiotic organic compounds prevailing on Earth.

关键词： abiotic hydrocarbons high P-T methane abiotic solid organic compounds deep carbon cycle

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云蒙山变质核杂岩抬升过程中伸展拆离和岩浆底辟联合作用的证据

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地学前缘 2007年第4期14卷 26-39页

作者：张家声 C.W.Passchier J.Konopasek 牛向龙黄雄南中国地震局地质研究所北京100029 institut für geowissenschaften University of Mainz

北京地区云蒙山变质核杂岩在白垩纪阶段抬升的早期,伴随着沿四合堂剪切带由北向南的拆离滑脱和大型花岗闪长岩的垂向侵位,晚期变形发生在花岗闪长岩岩基周边及其邻近围岩中,形成云蒙山剪切带,并伴随大量同构造的花岗岩和伟晶岩岩脉灌入... 详细信息

北京地区云蒙山变质核杂岩在白垩纪阶段抬升的早期,伴随着沿四合堂剪切带由北向南的拆离滑脱和大型花岗闪长岩的垂向侵位,晚期变形发生在花岗闪长岩岩基周边及其邻近围岩中,形成云蒙山剪切带,并伴随大量同构造的花岗岩和伟晶岩岩脉灌入。剪切带中所有的岩脉都随时间发生了不同程度的变形,较老的岩脉形成紧闭的圆柱状褶皱,枢纽与剪切带的线理和面理接近平行。岩脉与剪切带中L-S组构的平行化作用主要是由于这种转动的结果。岩脉的成分和长英指数随它们的变形程度发生变化,说明持续的岩浆分异作用与韧性剪切变形是同时发生的。云蒙山剪切带由岩浆底辟引起的上盘岩石重力所驱动,并不断得到同构造侵位岩脉的补充,起到存储和不断改造侵位岩脉的作用。早期伸展体制下形成的四合堂剪切带局部遭受云蒙山剪切带的改造或复合。该地区的岩石、构造和同构造岩脉的变形几何学和运动学证据表明,太古宙结晶基底的抬升是下部岩浆底辟与上部地壳伸展拆离共同作用的结果。

关键词：核杂岩岩脉韧性剪切带岩浆底辟拆离

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Temperature-depth control of petroleum occurrence in the sedimentary section of the South Caspian basin

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Petroleum research 2020年第1期5卷 70-76页

作者： A.A.feyzullayev Ian Lerche institute of Geology and Geophysics of Azerbaijan National Academy of Sciences H.Cavid av.119BakuAZ1143Azerbaijan institut fur geowissenschaften Naturwissenschaftliche FakultatⅢMartin-Luther-UniversitatGermany

This study analyses the temperature and depth control of well productivity(oil and gas),density of hydrocarbons(HC)and gas/liquid HC ratio(GLr)of petroleum fields in the South Caspian Basin(SCB).The database includes more than 700 field data from 54 onshore and offshore fields,which were processed to provide graphical and statistical analysis using standard computer *** was established that the peak of initial production and proven oil reserves falls in the temperature range 50-70℃.The oils of this interval are characterized by medium(about 890 kg/m^(3))and light(about 806 kg/m^(3))*** maximum condensate and gas production are in the temperature range 100-120℃,associated with the discovery and operation of large gas condensate fields in the deepwater part of the *** HC are represented in this temperature interval by“volatile”oils and condensates with an average density of 777-802 kg/m^(3).Low values of GLr are typical for temperatures below 70℃,associated both with poor gas conservation conditions and relatively high volumes of oil *** carbon isotope composition of methane indicates an exclusively catagenetic(thermal)origin at temperatures>50℃ and both catagenetic and mixed(microbiological-catagenetic)at temperaturesresults,a forecast is provided for the discovery of new commercial HC accumulations.

关键词： Oil Condensate Gas Well productivity Temperature zonality SCB

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Late Proterozoic magmatism and metamorphism recorded in gneisses from the Dabie high-pressure metamorphic zone,eastern China:evidence from zircon U-Pb geochronology

Late Proterozoic magmatism and metamorphism recorded in gnei...

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中国科学院地质与地球物理研究所2003学术年会

作者： Wolfgang Siebel Muharrem Satir institut für geowissenschaften Universitt TübingenWilhelmstraβe 5672074 TübingenGermany

This study presents zircon ages and geochemical and Nd-isotopic data for metagranites and quartzites from the Susong high-pressure metamorphic zone in the Dabie-Sulu ultrahigh-pressure collisional *** belt belongs to the eastern part of the Qinling-Dabie orogenic belt that formed during Early Mesozoic collision of the North and South China *** metagranites give zircon U-Pb model ages of 785±7 and 205±12 *** representing a Late Proterozoic magmatic event and an Early Mesozoic *** have low initialε-values(-12.4 and -11.1 at 780 Ma),favouring a crustal *** heavy rare earth elements(rEE) patterns(Gd/Yb～1.2) probably reflect that melting took place at a shallow crustal section where heavy-rEE-bearing mineral phases are *** zircons of three quartzites yield young discordant U-Pb ages and define a discordia with U-Pb model ages of 784±6 and 213±3 *** to those of the *** assume that all detrital zircons had lost radiogenic Pb prior to the Early Mesozoic overprint,probably facilitated by fluid participation during a metamorphic event contemporaneous with the intrusion of the *** simultaneous metamorphic and magmatic event was probably related to a rift setting along the periphery of the Yangtze(South China) Block during Late Proterozoic.

关键词： Dabie Late Proterozoic Magmatism Metamorphism Zircon U-Pb age

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Geochemical and isotopic composition and inherited zircon ages as evidence for lower crustal origin of two Variscan S-type granites in the NW Bohemian massif

Geochemical and isotopic composition and inherited zircon ag...

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中国科学院地质与地球物理研究所2003学术年会

作者： W.Siebel M.Satir institut für geowissenschaften Universitt TübingenWilhelmstraβe 5672074 TübingenGermany

Geochemical and Nd-Sr isotopic compositions and U-Pb zircon ages of two Variscan granites(Neunburg and Oberviechtach) from southern Oberpfalz,NW Bohemian massif,have been investigated in order to place constraints on their formation and on the crustal reworking. Both granites exhibit similar mineralogical,chemical and isotopic *** have peraluminous compositions(A/CNK ratios 1.2-1.3) and display high K

关键词： Moldanubian Nd-Sr isotopes S-type granite Variscan Zircon age

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recurrent hardgrounds and their significance for intra-basinal correlations:a case study of upper Bathonian rocks from the western margin of the Indian craton

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Journal of Palaeogeography 2019年第1期8卷 19-30页

作者： Dhirendra K.Pandey franz T.fürsich Matthias Alberti Jitendra K.Sharma Narendra Swami Earth and Planetary Sciences Group Manipal Center for Natural SciencesCentre of Excellence Dr. TMA Pai Planetarium Building Manipal Academy of Higher Education fG Pal?oumwelt GeoZentrum Nordbayern Friedrich-Alexander Universit?t Erlangen-Nürnberg institut für geowissenschaften Christian-Albrechts-Universit?t zu Kiel Department of Geology University of Rajasthan Himalayan Geology Division Geological Survey of India Northern Region

A set of two to three prominent hardgrounds can be traced for more than 40 km from east to west within the Jurassic succession of the Jaisalmer Basin at the western margin of the Indian Craton. The hardgrounds started to form under subtidal conditions in a mixed carbonate–siliciclastic setting during the last phase of a transgressive systems tract, i.e. the maximum flooding zone. The age difference between the hardgrounds is very small, but they differ lithologically. Typically, the stratigraphically oldest hardground occurs at the top of a 1-m-thick calcareous sandstone. It is characterized by a spectacular megaripple surface encrusted with oysters and subsequently occasionally bored by bivalves. The hardground is overlain by 10–25 cm of biowackestone to biopackstone, at the top of which another hardground is developed. This second hardground is characterized by abundant bivalve(Gastrochaenolites isp.) and "worm" borings(Trypanites and Meandropolydora isp.) and occasional oyster encrustations. The third hardground can be found within the overlying 60-cm-thick, bioturbated, fossiliferous silty marly packstone. It shows common to abundant oyster encrustations and occasional borings together with reworked concretions. The individual hardground can be well recognized throughout the basin based on lithology and biotic components. The second hardground(biowackestone to biopackstone) with abundant bivalve and worm borings is most prominent and widespread. Lithostratigraphically, these three hardground surfaces belong to the uppermost part of the Bada Bag Member of the Jaisalmer formation. Based on ammonites, such as Perisphinctes congener(Waagen), brachiopods, and corals, this interval of the Bada Bag Member has been assigned a late Bathonian age. The entire succession above the first hardground is bioturbated up to the overlying marly silt of the Kuldhar Member of the Jaisalmer formation, which is already Callovian in age. The characteristic hardground lithologies, toget

关键词： Hardgrounds Stratigraphy Palaeoenvironment Jurassic Jaisalmer Basin

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first steps in reconstructing Early Jurassic sea water temperatures in the Andean Basin of northern Chile based on stable isotope analyses of oyster and brachiopod shells

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Journal of Palaeogeography 2020年第1期9卷 71-87页

作者： Matthias Alberti franz T.fürsich Nils Andersen institut für geowissenschaften Christian-Albrechts-Universitat zu KielLudewig-Meyn-Straβe 1024118 KielGermany GeoZentrum Nordbayern Fachgruppe PalaoUmweltFriedrich-Alexander-Universitat Erlangen-NürnbergLoewenichstraβe 2891054 ErlangenGermany Leibniz Laboratory for radiometric Dating and Stable Isotope research Christian-Albrechts-Universitat zu KielMax-Eyth-Straβe 1124118 KielGermany

The stable isotope(δ13 C,δ18 O)composition of a collection of Lower Jurassic brachiopods and oysters from the Andean Basin of northern Chile was *** results allow the first reconstruction of absolute water temperatures for several ammonite zones in the Lower Jurassic of South *** temperature record starts with comparatively high values in the Late Sinemurian(average:27.0℃;raricostatum Zone).Just before the Sinemurian–Pliensbachian transition,temperatures dropped to an average of 24.3℃.The lowest temperature value in the dataset was recorded for a brachiopod shell of the latest Pliensbachian Spinatum Zone(19.6℃).No data are available for the Early Toarcian,but results for the late Toarcian show again comparatively warm conditions(average:24.4℃;Thouarsense–Levesquei zones).Even though more material and analyses are necessary to corroborate the recorded temperatures,the present dataset seems to indicate the global nature of the Late Pliensbachian Cooling *** contrast,the global warming during the Toarcian Oceanic Anoxic Event has not been recorded due to a lack of Early Toarcian ***δ13 C record of brachiopods and oysters documents a gradual increase in values representing background *** shells were used for high-resolution stable isotope analyses and show seasonal temperature fluctuations over a period of around 3 years in the life time of the *** explained only by temperatures,theδ18 O values point to a minimum estimate for the seasonality in the late Toarcian of slightly more than 3℃.

关键词： Early Jurassic Chile Stable isotopes Palaeoclimate Water temperatures Seasonality

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A TAXONOMICAL AND ECOLOGICAL OVErVIEW Of rECENT AND HOLOCENE OSTrACODES Of THE NAM CO rEGION, SOUTHErN TIBET

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第四纪研究 2009年第4期29卷 665-677页

作者： C. Wrozyna P. frenzel Manping Xie Liping Zhu A. Schwalb institut far Umweltgeologie Technische Universit~it Braunschweig PockelsstraBe 3 38106 Braunschweig Germany institut fur geowissenschaften Friedrich-Schiller-Universitat Burgweg 11 07749 Jena Germany institute of Tibetan Plateau research Chinese Academy of Sciences BeijingChina

We present a list of living and (sub) fossil Ostracoda (Crustacea) from Holocene sediments from Lake NamCo,Southern Tibet, including descriptions, distribution and ecological data of the important taxa from the Nam Cocatchment. Species associations from lake surface sediments, sediment cores and outcrop samples consist of eight speciesincluding Candona candida ( O.f. Müller, 1776 ) , Candona xizangensis ( Huang, 1982 ) , Eucypris afghanistanensis( Hartmann, 1964) , fabaeformiscandona danielopoli ( Yin & Martens, 1997 ) , Ilyocypris cf. mongolica ( Martens, 1991 ) ,? Leucocythere dorsotuberosa ( Huang, 1982 ) , Leucocytherella sinensis ( Huang, 1982 ) and Limnocythere inopinata ( Baird,1843). The dominant species are ? L. dorsotuberosa and L. sinensis. They show morphological variations with different degreesof ornamentation. We regard the variable noding and rib formation as intraspecific variability possibly driven byenvironmental factors. In general,the number and degree of ribs increases with water depth in ? L. dorsotuberosa. Thus,theornamentation may present a means to reconstruct(paleo) water depths. Our list is intended to serve as a taxonomical andpaleoecological primer for future paleolimnological work.

关键词：化石甲壳类西藏沉积物

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