East China (east + china)

Distribution by Scientific Domains

Terms modified by East China

  • east china sea

  • Selected Abstracts


    Inter-decadal variation of the summer precipitation in East China and its association with decreasing Asian summer monsoon.

    INTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 9 2008
    Part I: Observed evidences
    Abstract In recent two decades, North and Northeast China have suffered from severe and persistent droughts while the Yangtze River basin and South China have undergone much more significant heavy rainfall/floods events. This long-term change in the summer precipitation and associated large-scale monsoon circulation features have been examined by using the new dataset of 740 surface stations for recent 54 years (1951,2004) and about 123-yr (1880,2002) records of precipitation in East China. The following new findings have been highlighted: (1) One dominating mode of the inter-decadal variability of the summer precipitation in China is the near-80-yr oscillation. Other modes of 12-yr and 30,40-yr oscillations also play an important role in affecting regional inter-decadal variability. (2) In recent 54 years, the spatial pattern of the inter-decadal variability of summer precipitation in China is mainly structured with two meridional modes: the dipole pattern and the positive-negative-positive ("+ , + " pattern). In this period, a regime transition of meridional precipitation mode from "+ , + " pattern to dipole pattern has been completed. In the process of southward movement of much precipitation zone, two abrupt climate changing points that occurred in 1978 and 1992, respectively, were identified. (3) Accompanying the afore-described precipitation changes, the East Asian summer monsoon have experienced significant weakening, with northward moisture transport and convergence by the East Asian summer monsoon greatly weakened, thus leading to much deficient moisture supply for precipitation in North China. (4) The significant weakening of the component of the tropical upper-level easterly jet (TEJ) has made a dominating contribution to the weakening of the Asian summer monsoon system. The cooling in the high troposphere at mid- and high latitudes and the possible warming at low latitude in the Asian region is likely to be responsible for the inter-decadal weakening of the TEJ. Copyright © 2007 Royal Meteorological Society [source]


    Mineral evolution of a garnet-pyroxenite nodule within eclogite, eastern Sulu ultrahigh-pressure metamorphic terrane, East China

    JOURNAL OF METAMORPHIC GEOLOGY, Issue 8 2005
    T. N. YANG
    Abstract Detailed microtextural observations and bulk chemical analysis were undertaken on a garnet-pyroxenite nodule within retrograde eclogites from the NE Sulu ultrahigh-pressure metamorphic (UHPM) terrane. The results suggest that the protolith was a cumulate from a gabbroic body. The nodule consists primarily of coarse clinopyroxene grains with a very high content of the Ca-Tschermakite molecule. Microscopic observations and back-scattered electron images (BSE) demonstrate a complicated intergrowth of clinopyroxene, garnet and ilmenite, which represents the peak metamorphic assemblage. The primary clinopyroxene grains are armoured with a thin garnet corona up to 0.5 mm wide that forms an interconnected network. Within the clinopyroxene grains, four sets of garnet lamellae are distributed along crystallographic planes; locally, a vermicular intergrowth of garnet and diopside is developed. Besides the garnet, parallel arrays of ilmenite blebs are common within the clinopyroxene. Hydrous minerals such as amphibole, zoisite and titanite formed at later stages, and replaced diopside, garnet and ilmenite respectively. The P,T conditions determined for the formation of the garnet lamellae indicate that the garnet pyroxenite experienced UHP metamorphism at the same peak P,T condition as its host eclogite. The very high Ca-Tschermakite content (31,34 mol.%) of the primary clinopyroxene indicates crystallization at about 9,17 kbar and 1250,1450 °C, and together with the microtextural observations, suggests that the protolith of the garnet pyroxenite was a cumulate from a former gabbroic body, in which case, the host eclogite might represent the gabbroic body. [source]


    Differentiation of golden-ringed dragonfly Anotogaster sieboldii (Selys, 1854) (Cordulegastridae: Odonata) in the insular East Asia revealed by the mitochondrial gene genealogy with taxonomic implications

    JOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 2 2008
    T. Kiyoshi
    Abstract Molecular phylogeographical analyses of Anotogaster sieboldii (Selys, 1854) were conducted to reveal the differentiation process of insular populations. The gene genealogy based on 845 bp of the mitochondrial genes (cytochrome oxidase subunit I and subunit II) indicated that A. sieboldii includes two deeply separated lineages. These two major lineages seem to have differentiated in Miocene before the formation of the insular East Asia. One lineage includes three inner clades that correspond to the populations of northern area (the Japanese main islands, Korean Peninsula, Yakushima), Amamioshima and Okinawajima. Populations of Central Ryukyu, including Amamioshima and Okinawajima, might have been divided from the northern populations in early Pleistocene. The other major lineage includes populations of the Yaeyama Group, Taiwan and East China. The former two populations were reconstructed as a reciprocal monophyletic group. Populations of Taiwan and Yaeyama Groups would have been separated from the continental ones in Pleistocene. These two highly divergent lineages should be recognized as distinct species. Furthermore, the mitochondrial lineages revealed six genetically distinct and geographically isolated assemblages: (1) northern populations, (2) Amamioshima, (3) Okinawajima, (4) Yaeyama Group, (5) Taiwan and (6) East China. Zusammenfassung An der Libelle Anotogaster sieboldii wurden molekulare phylogeographische Analysen durchgeführt, um ihre Differenzierungen in Insel-Populationen zu erkennen. Die Gen-Genealogie (basierend auf 845 bp mitochondrialer Gene (COI und COII) zeigte, dass A. sieboldii zwei weit getrennte Abstammungslinien enthält, die sich wahrscheinlich im Miozän vor der Bildung der ostasiatischen Inselwelt differenzierten. Eine Abstammungslinie schließt drei Gruppierungen ein, die den Populationen in den nördlichen Gebieten entsprechen: die japanischen Hauptinseln, die koreanische Halbinsel Yakushima, Amamioshima sowie Okinawajima. Die Populationen von Zentral-Ryukyu, einschließlich Amamioshima und Okinawajima, ist möglicherweise im frühen Pleistozän von den nördlichen Populationen getrennt worden. Die andere größere Abstammungslinie schließt die Populationen der Yaeyama-Gruppe, Taiwan und das Östliche China ein. Zwei dieser Populationen wurden als Teil einer entsprechenden monophyletischen Gruppe rekonstruiert; die Populationen von Taiwan und die Yaeyama-Gruppe sind danach im Pleistozän von den kontinentalen Populationen getrennt worden. Diese zwei sehr differierenden Abstammungslinien sollten als verschiedene Spezies betrachtet werden. Weiterhin werden sechs genetisch verschiedene und geographisch isolierte Gruppierungen deutlich: (1) die nördlichen Populationen, (2) Amamioshima, (3) Okinawajima, (4) die Yaeyama-Gruppe, (5) Taiwan und (6) die Population im östlichen China. [source]


    Surviving the end-Ordovician extinctions: evidence from the earliest Silurian brachiopods of northeastern Jiangxi and western Zhejiang provinces, East China

    LETHAIA, Issue 1 2006
    JIA-YU RONG
    Earliest Rhuddanian (Silurian) brachiopods are recorded from the basal part of the Lower Llandovery Shiyang and Anji formations in western Zhejiang and northeastern Jiangxi provinces, East China. Associated graptolites including Normalograptus jerini indicate the lowest Rhuddanian Akidograptus ascensus Biozone. The surviving brachiopod fauna includes 19 genera dominated by orthids and strophomenids, whereas pentamerids and atrypids that inhabited mainly warmer water regimes, and were almost absent in the cool/cold Hirnantia Fauna, occur rarely in the studied fauna. Each family is represented by a single genus that seeded their recovery. The predominance of these long-ranging and widely distributed genera is one of major characters of the brachiopod survival in east China. From qualitative and quantitative analysis of faunal composition, diversity and abundance, with evidences from palaeoecology and palaeogeography, the Levenea qianbeiensis Association, Katastrophomena-Leptaena-Levenea Association, and Glyptorthis-Epitomyonia-Levenea Association are recognized and assigned to BA (Benthic Assemblage) 2, BA3, and an ecozone close to the BA3-4 boundary respectively. No Lazarus genera are recorded in this study. Skenidioides and Epitomyonia were chiefly regarded as deeper-water taxa in the Ordovician and Silurian, but are recorded from shallow-water in east China during the early Rhuddanian, indicating an ecologic experiment with these taxa migrating from deep into shallower, better-oxygenated sites at the crisis time and during the subsequent survival interval. This study further demonstrates that the brachiopod faunal turnover after the end-Ordovician extinctions may not have been completed until the late Rhuddanian in South China. [source]


    Prevalence and risk factors for anaemia in pregnant women: a population-based prospective cohort study in China

    PAEDIATRIC & PERINATAL EPIDEMIOLOGY, Issue 4 2009
    Qiaoyi Zhang
    Summary Maternal anaemia is a common pregnancy complication in developing countries; however, its epidemiology remains largely unexplored in China. This study was designed to explore the epidemiology and risk factors of anaemia during pregnancy. A prospective cohort study was conducted, using data from a population-based pregnancy-monitoring system in 13 counties in East China (1993,96). Women who delivered singleton infants at 20,44 weeks with at least one haemoglobin assessment during pregnancy were included (n = 164 667). The prevalence of anaemia (haemoglobin < 10 g/dL) during pregnancy as well as in each trimester was estimated. Multivariable log-binomial regression models were used to evaluate risk factors. The overall prevalence of anaemia in pregnancy was 32.6%, with substantial variations across trimesters (11.2%, 20.1% and 26.2% in the 1st, 2nd and 3rd trimesters respectively). Risk factors for anaemia included older maternal age, education below junior high school (prevalence rate ratio [RR] 1.10, 95% confidence interval [CI] 1.08, 1.12), farming occupation (1.05, 95% CI 1.03, 1.06), and mild pregnancy-induced hypertension (PIH) (RR 1.09, 95% CI 1.05, 1.13) and severe PIH (RR 1.13, 95% CI 1.06, 1.19). Peri-conception folic acid use was associated with a reduced risk for anaemia in the 1st trimester (RR 0.75, 95% CI 0.72, 0.78). Initiating prenatal care after the 1st trimester was associated with increased risk of anaemia in the 2nd and 3rd trimesters. Our study found anaemia during pregnancy is highly prevalent in this indigenous Chinese population. The risk increases with the severity of hypertensive disorders. Folic acid supplementation during the peri-conception period is associated with reduced risk of 1st trimester anaemia. [source]


    Political Booms: Local Money and Power in Taiwan, East China, Thailand, and the Philippines , By Lynn White

    ASIAN POLITICS AND POLICY, Issue 3 2010
    Rowena Rivera Pangilinan
    No abstract is available for this article. [source]


    40Ar/39Ar Dating of Deformation Events and Reconstruction of Exhumation of Ultrahigh-Pressure Metamorphic Rocks in Donghai, East China

    ACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 2 2003
    LI Jinyi
    Abstract Recent investigations reveal that the ultrahigh-pressure metamorphic (UHPM) rocks in the Donghai region of East China underwent ductile and transitional ductile-brittle structural events during their exhumation. The earlier ductile deformation took place under the condition of amphibolite facies and the later transitional ductile-brittle deformation under the condition of greenschist facies. The hanging walls moved southeastward during both of these two events. The 40Ar/39Ar dating of muscovites from muscovite-plagioclase schists in the Haizhou phosphorous mine, which are structurally overlain by UHPM rocks, yields a plateau age of 218.0±2.9 Ma and isochron age of 219.8Ma, indicating that the earlier event of the ampibolite-facies deformation probably took place about 220 Ma ago. The 40Ar/39Ar dating of oriented amphiboles parallel to the movement direction of the hanging wall on a decollement plane yields a plateau age of 213.1 ± 0.3 Ma and isochron age of 213.4±4.1 Ma, probably representing the age of the later event. The dating of pegmatitic biotites and K-feldspars near the decollement plane from the eastern Fangshan area yield plateau ages of 203.4±0.3 Ma, 203.6±0.4 Ma and 204.8±2.2 Ma, and isochron ages of 204.0±2.0 Ma, 200.6±3.1 Ma and 204.0±5.0 Ma, respectively, implying that the rocks in the studied area had not been cooled down to closing temperature of the dated biotites and K-feldspars until the beginning of the Jurassic (about 204 Ma). The integration of these data with previous chronological ages on the ultrahigh-pressure metamorphism lead to a new inference on the exhumation of the UHPM rocks. The UHPM rocks in the area were exhumed at the rate of 3,4 km/Ma from the mantle (about 80,100 km below the earth's surface at about 240 Ma) to the lower crust (at the depth of about 20-30km at 220 Ma), and at the rate of 1,2 km/Ma to the middle crust (at the depth of about 15 km at 213 Ma), and then at the rate of less than 1 km/Ma to the upper crust about 10 km deep at about 204 Ma. [source]


    Helium Isotope Geochemistry of Ultrahigh-Pressure Metamorphic Eclogites From the Dabie-Sulu Terrane in East China

    ACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 1 2000
    LI Yanhe
    Abstract: The 3He/4He ratios of most eclogites from the Dabie-Sulu terrane range from 0.056 to 0.67 Ra; the data points fall into the mixing part of the crust and the mantle in the 3He- 4He diagram. The 3He/4He ratios of eclogites are obviously correlated with the types of their surrounding rocks. The helium isotope composition of the eclogites from the Bixiling complex possesses characters of mantle-derived rocks with the 3He/4He ratio being 5.6 Ra. The 4He concentration of the eclogites exhibits visible inverse correlation with the ,18O value of the quartz in the eclogites from the Sulu area. The ,18O values of the eclogites change synchronously with those of the country rocks. Those results suggest that protoliths of the eclogites were basic-ultrabasic rock bodies or veins intruding into the continental crust in the early stage; strong exchange and hybridization between the basic-ultrabasic rocks and continental rocks and the atmospheric water during the intrusion led to abrupt increase of the 3He/4He ratios, ,18O values and Nd(0) values of the intrusive bodies or veins, which show characters of continental rocks. This indicates that the eclogites are autochthonous. [source]


    Distribution of polycyclic aromatic hydrocarbons in particle-size separates and density fractions of typical agricultural soils in the Yangtze River Delta, east China

    EUROPEAN JOURNAL OF SOIL SCIENCE, Issue 6 2008
    J. Z. Ni
    Summary Soil organic matter can be divided into different organic carbon (C) pools with different turnover rates. The organic pollutants in soils associated with these organic C pools may have different bioavailability and environmental risks during the decomposition of soil organic matter. We studied the distribution patterns of 15 USEPA priority polycyclic aromatic hydrocarbons (PAHs) in different particle-size separates (clay, fine silt, coarse silt, fine sand and coarse sand) and density fractions (light and heavy fractions) of nine agricultural topsoils (0,20 cm depth) from a contaminated area in the Yangtze River Delta region of east China. There was a decreasing trend in PAH concentration in particle-size separates with decreasing particle size. However, the different particle-size separates had similar PAH composition. The concentration of PAHs in the light fraction ranged from 13 037 to 107 299 ,g kg,1, far higher than in the heavy fraction, which ranged from 222 to 298 ,g kg,1. Although the light fraction accounted for only 0.4,2.3% of the soils, it was associated with 31.5,69.5% of soil PAHs. The organic matter in coarse silt had the strongest capacity for enrichment with PAHs. Combining the distributions of PAHs and the turnover rates of organic matter in different soil fractions, the environmental risks of PAH-polluted soils may be due mainly to the PAHs associated with sand and the light fraction. [source]


    Surviving the end-Ordovician extinctions: evidence from the earliest Silurian brachiopods of northeastern Jiangxi and western Zhejiang provinces, East China

    LETHAIA, Issue 1 2006
    JIA-YU RONG
    Earliest Rhuddanian (Silurian) brachiopods are recorded from the basal part of the Lower Llandovery Shiyang and Anji formations in western Zhejiang and northeastern Jiangxi provinces, East China. Associated graptolites including Normalograptus jerini indicate the lowest Rhuddanian Akidograptus ascensus Biozone. The surviving brachiopod fauna includes 19 genera dominated by orthids and strophomenids, whereas pentamerids and atrypids that inhabited mainly warmer water regimes, and were almost absent in the cool/cold Hirnantia Fauna, occur rarely in the studied fauna. Each family is represented by a single genus that seeded their recovery. The predominance of these long-ranging and widely distributed genera is one of major characters of the brachiopod survival in east China. From qualitative and quantitative analysis of faunal composition, diversity and abundance, with evidences from palaeoecology and palaeogeography, the Levenea qianbeiensis Association, Katastrophomena-Leptaena-Levenea Association, and Glyptorthis-Epitomyonia-Levenea Association are recognized and assigned to BA (Benthic Assemblage) 2, BA3, and an ecozone close to the BA3-4 boundary respectively. No Lazarus genera are recorded in this study. Skenidioides and Epitomyonia were chiefly regarded as deeper-water taxa in the Ordovician and Silurian, but are recorded from shallow-water in east China during the early Rhuddanian, indicating an ecologic experiment with these taxa migrating from deep into shallower, better-oxygenated sites at the crisis time and during the subsequent survival interval. This study further demonstrates that the brachiopod faunal turnover after the end-Ordovician extinctions may not have been completed until the late Rhuddanian in South China. [source]


    A New, Weil-Preserved Species of Glaresidae (Coleoptera: Scarabaeoidea) from the Jehol Biota of China

    ACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 4 2010
    BAI Ming
    Abstract: Glaresis orthochilus sp. nov. (Scarabaeoidea: Glaresidae), the best preserved glaresid fossil, is described and illustrated from the Yixian Formation of western Liaoning province, north,east China. Glaresidae, the sister group of all extant Scarabaeoidea was established in the Upper Jurassic/Lower Cretaceous and contained larger species than those found today. [source]


    Geologic Characteristics of Volcanic Hydrocarbon Reservoirs and Exploration Directions in China

    ACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 1 2010
    Caineng ZOU
    Abstract: Volcanic rocks are distributed widely in China, which are important exploration targets. By analyzing many discovered volcanic hydrocarbon reservoirs all over the world, the authors summarized the geologic characteristics of the formation of volcanic hydrocarbon reservoirs in China, and gave further exploration directions and advices. (1) There are mainly Carboniferous-Permian, Jurassic-Cretaceous, Paleogene-Neogene volcanic rocks in oil- and gas-bearing basins in China, which are mainly distributed in the Junggar Basin, Songliao Basin, Bohai Bay Basin, etc. There are mainly intermediate rocks and acidic rocks in east China, and intermediate rocks and basic rocks in west China. They primarily develop in intracontinental rift settings and island are environments. (2) Porefissure reservoirs are distributed widely in basins, which are volcanic rocks mainly in explosive and effusive facies. (3) Volcanic hydrocarbon reservoirs are chiefly near-source lithostratigraphic hydrocarbon reservoirs, and the oil and gas accumulation is predominantly controlled by lithotypes, faults and structural positions. (4) Deep-seated oil and gas reservoirs in the Songliao Basin and Carboniferous volcanic hydrocarbon reservoirs in the Junggar Basin are potential giant volcanic gas provinces, the volcanic hydrocarbon reservoirs in the Bohai Bay Basin and Santanghu Basin are favorable for oil and gas reserves increase, and volcanic rocks in the Turpan Basin, Sichuan Basin, Tarim Basin have exploration potentiality. (5) The technology series of oil and gas exploration in volcanic rocks have been preliminarily formed. [source]


    Palladium, Platinum and Gold Concentrations in Fengshan Porphyry Cu,Mo Deposit, Hubei Province, China

    ACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 5 2009
    Minfang WANG
    Abstract: The Fengshan porphyry-skarn copper,molybdenum (Cu,Mo) deposit is located in the south-eastern Hubei Province in east China. Cu,Mo mineralization is hosted in the Fengshan granodiorite porphyry stock that intruded the Triassic Daye Formation carbonate rocks in the early Cretaceous (,140 Ma), as well as the contact zone between granodiorite porphyry stock and carbonate rocks, forming the porphyry-type and skarn-type association. The Fengshan granodiorite stock and the immediate country rocks are strongly fractured and intensely altered by hydrothermal fluids. In addition to intense skarn alteration, the prominent alteration types are potassic, phyllic, and propylitic, whereas argillation is less common. Mineralization occurs as veins, stock works, and disseminations, and the main ore minerals are chalcopyrite, pyrite, molybdenite, bornite, and magnetite. The contents of palladium, platinum and gold (Pd, Pt and Au) are determined in nine samples from fresh and mineralized granodiorite and different types of altered rocks. The results show that the Pd content is systematically higher than Pt, which is typical for porphyry ore deposits worldwide. The Pt content ranges from 0.037 to 1.765 ppb, and the Pd content ranges between 0.165 and 17.979 ppb. Pd and Pt are more concentrated in porphyry mineralization than skarn mineralization, and have negative correlations with Au. The reconnaissance study presented here confirms the existence of Pd and Pt in the Fengshan porphyry-skarn Cu,Mo deposit. When compared with intracontinent and island arc geotectonic settings, the Pd, Pt, and Au contents in the Fengshan porphyry Cu,Mo deposit in the intracontinent is lower than the continental margin types and island are types. A combination of available data indicates that Pd and Pt were derived from oxidized alkaline magmas generated by the partial melting of an enriched mantle source. [source]