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我国东中西部地区间工业产业转移的趋势、特征及形成原因分析 被引量:160
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作者 冯根福 刘志勇 蒋文定 《当代经济科学》 CSSCI 北大核心 2010年第2期1-10,共10页
本文主要对1993年至2006年期间我国东中西部地区间工业产业转移的趋势和特征进行了初步分析,并探讨了我国东中西部地区间产业转移的趋势和特征的形成以及与传统的国际产业转移理论出现背离的原因。本文统计分析结果表明:截止到2006年,... 本文主要对1993年至2006年期间我国东中西部地区间工业产业转移的趋势和特征进行了初步分析,并探讨了我国东中西部地区间产业转移的趋势和特征的形成以及与传统的国际产业转移理论出现背离的原因。本文统计分析结果表明:截止到2006年,我国东中西部地区间只发生了部分的相对产业转移,绝对产业转移的现象尚未发生,我国东中西部地区间的产业转移还不显著;在我国东中西部地区间的产业转移过程中,出现了部分技术密集型产业先于劳动型密集型产业转移和许多产业越过中部地区直接转移到西部地区的现象。本文研究结论的重要启示是:同一国度内区域间的产业转移与国际产业转移的条件有着很大的不同,因此在分析我国地区间产业转移时不能机械照搬国际产业转移理论;目前我国东中西部地区间大规模产业转移的条件还不成熟,因而在相当长一个时期内,试图通过东中西部地区间的产业转移来实现我国的区域协调发展以及解决国际金融危机背景下我国产业结构调整与扩大就业之间的矛盾还是相当困难的。 展开更多
关键词 东中西部地区 产业转移 趋势与特征
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Petrogenesis of highly fractionated I-type granites in the Zayu area of eastern Gangdese, Tibet: Constraints from zircon U-Pb geochronology, geochemistry and Sr-Nd-Hf isotopes 被引量:116
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作者 ZHU DiCheng MO XuanXue +4 位作者 WANG LiQuan ZHAO ZhiDan NIU Yaoling ZHOU ChangYong YANG YueHeng 《Science China Earth Sciences》 SCIE EI CAS 2009年第9期1223-1239,共17页
The Cretaceous granitoids in the middle and northern Gangdese, Tibet are generally interpreted as the products of anatexis of thickened deep crust genetically associated with the Lhasa-Qiangtang collision. This paper ... The Cretaceous granitoids in the middle and northern Gangdese, Tibet are generally interpreted as the products of anatexis of thickened deep crust genetically associated with the Lhasa-Qiangtang collision. This paper reports bulk-rock major element, trace element and Sr-Nd isotopic data, zircon U-Pb age data, and zircon Hf isotopic data on the Zayu pluton in eastern Gangdese, Tibet. These data shed new light on the petrogenesis of the pluton. Our SHRIMP zircon U-Pb age dates, along with LA-ICPMS zircon U-Pb age dates recently reported in the literature, indicate that the Zayu pluton was emplaced at about 130 Ma, coeval with Early Cretaceous magmatic rocks in other areas of eastern Gangdese (e.g., Rawu, Baxoi areas) and the Middle Gangdese. The Zayu pluton samples lack amphibole and muscovite, and are compositionally characterized by high SiO2 (69.9%–76.8%), K2O (4.4%–5.7%), and low P2O5 (0.05%–0.12%). These samples also have A/CNK values of 1.00–1.05, and are enriched in Rb, Th, U, and Pb, and depleted in Ba, Nb, Ta, Sr, P, Ti, and Eu. These geochemical features suggest that the Zayu pluton samples are metaluminous to slightly peraluminous and are of highly fractionated I-type granite. The Zayu pluton samples have high ? Nd(t) values (?10.9–?7.6) and low initial 87Sr/86Sr ratios (0.7120–0.7179) relative to melts derived from mature continental crust in the Gangdese (e.g., Ningzhong Early Jurassic strongly peraluminous granite). The Zayu pluton samples are heterogeneous in zircon ? Hf(t) values (?12.8–?2.9), yielding ancient zircon Hf crustal model ages of 1.4–2.0 Ga. The data obtained in this study together with the data in the recent literature suggest that the Early Cretaceous granitoids in eastern Gangdese represent the eastward extension of the Early Cretaceous magmatism in the middle Gangdese, and that the Lhasa micro-continent block with ancient basement may extend for ~2000 km from east to west. Zircon Hf isotopic data and bulk-rock zircon saturation temperature (789–821 °C) indicate t 展开更多
关键词 zircon U-Pb dating Sr-Nd-Hf isotope HIGHLY fractionated I-TYPE granite Zayu PLUTON eastern GANGDESE TIBET
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Meteorological conditions for the persistent severe fog and haze event over eastern China in January 2013 被引量:118
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作者 ZHANG RenHe LI Qiang ZHANG RuoNan 《Science China Earth Sciences》 SCIE EI CAS 2014年第1期26-35,共10页
In January 2013,a severe fog and haze event(FHE)of strong intensity,long duration,and extensive coverage occurred in eastern China.The present study investigates meteorological conditions for this FHE by diagnosing bo... In January 2013,a severe fog and haze event(FHE)of strong intensity,long duration,and extensive coverage occurred in eastern China.The present study investigates meteorological conditions for this FHE by diagnosing both its atmospheric background fields and daily evolution in January 2013.The results show that a weak East Asian winter monsoon existed in January2013.Over eastern China,the anomalous southerly winds in the middle and lower troposphere are favorable for more water vapor transported to eastern China.An anomalous high at 500 hPa suppresses convection.The weakened surface winds are favorable for the fog and haze concentrating in eastern China.The reduction of the vertical shear of horizontal winds weakens the synoptic disturbances and vertical mixing of atmosphere.The anomalous inversion in near-surface increases the stability of surface air.All these meteorological background fields in January 2013 were conducive to the maintenance and development of fog and haze over eastern China.The diagnosis of the daily evolution of the FHE shows that the surface wind velocity and the vertical shear of horizontal winds in the middle and lower troposphere can exert dynamic effects on fog and haze.The larger(smaller)they are,the weaker(stronger)the fog and haze are.The thermodynamic effects include stratification instability in middle and lower troposphere and the inversion and dew-point deficit in near-surface.The larger(smaller)the stratification instability and the inversion are,the stronger(weaker)the fog and haze are.Meanwhile,the smaller(larger)the dewpoint deficit is,the stronger(weaker)the fog and haze are.Based on the meteorological factors,a multi-variate linear regression model is set up.The model results show that the dynamic and thermodynamic effects on the variance of the fog and haze evolution are almost the same.The contribution of the meteorological factors to the variance of the daily fog and haze evolution reaches 0.68,which explains more than 2/3 of the variance. 展开更多
关键词 fog and haze event meteorological conditions eastern China January 2013
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Spatio-temporal analysis of land-use conversion in the eastern coastal China during 1996-2005 被引量:95
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作者 LIU Yansui WANG Lijuan LONG Hualou 《Journal of Geographical Sciences》 SCIE CSCD 2008年第3期274-282,共9页
Based on the acquaintance of the regional background of urban-rural transformational development and investigations on the spot,this paper discusses the holistic situation, dominant factors and mechanism of arable lan... Based on the acquaintance of the regional background of urban-rural transformational development and investigations on the spot,this paper discusses the holistic situation, dominant factors and mechanism of arable land loss and land for construction occupation in the coastal area of China over the last decade,with the aid of GIS technology.Conclusions of the research are summarized as follows:(1)the arable land had been continuously decreasing from 1996 to 2005,with a loss of 1,708,700 hm^2 and an average decrement of 170,900 hm^2 per year;(2)land for construction increased 1,373,700 hm^2 ,with an average increment of 153,200 hm^2 per year;(3)total area of encroachment on arable land for construction between 1996 and 2005 was 1,053,100 hm^2 ,accounting for 34.03%of the arable land loss in the same period,the percentages of which used for industrial land(INL),transportation land(TRL),rural construction land(RUL)and town construction land(TOL)are 45.03%,15.8%,15.47%and 11.5%,respectively;and(4)the fluctuation of the increase of construction land and encroachment on arable land in the area were deeply influenced by the nation's macroscopic land-use policies and development level of regional economy.The growth of population and advancement of technology promoted the rapid industrialization, construction of transportation infrastructures,rural urbanization and expansion of rural settlements in the eastern coastal area,and therefore were the primary driving forces of land-use conversion. 展开更多
关键词 urban-rural harmonious development rural urbanization new countryside construction arable land loss the eastern coastal China
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Time range of Mesozoic tectonic regime inversion in eastern North China Block 被引量:92
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作者 ZHAI Mingguo ZHU Rixiang +7 位作者 LIU Jianming MENG Qingren HOU Quanlin HU Shengbiao LIU Wei LI Zhong ZHANG Hongfu ZHANG Huafeng 《Science China Earth Sciences》 SCIE EI CAS 2004年第2期151-159,共9页
An important tectonic inversion took place in eastern North China Block(NCB) during Mesozoic, which caused a great lithosphere thinning, reconstruction of basin-range series, powerful interaction between mantle and cr... An important tectonic inversion took place in eastern North China Block(NCB) during Mesozoic, which caused a great lithosphere thinning, reconstruction of basin-range series, powerful interaction between mantle and crust, a vast granitic intrusion and volcanism, and large-scale metallogenic explosion. The time range of the Mesozoic tectonic regime inversion in the eastern North China Block is one of the key issues to understand mechanism of tectonic regime inversion. Our updated results for recognizing the time range are mainly obtained from the following aspects: structural analyses along northern and southern margins of the NCB and within the NCB for revealing tectonic inversion from compression to extension and structural striking from ~EW to NNE; geothermic analyses of the eastern sedimental basins for a great change of thermal history and regime; basin analysis for basin inversion from compression to extension and basin migration from ~EW to NNE; petrological and geochemical studies of volcanic rocks and lowermost crust xenoliths for recognizing peak period of mantle upwelling and intense interaction between mantle and crust, and main metallogenic epoch. All the studies of the above give the same time range from~150-140 Ma to ~110-100Ma, peaking at ~120 Ma. 展开更多
关键词 eastern NCB MESOZOIC tectonic regime inversion time range
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Magmatic Event at the End of the Archean in Eastern Hebei Province and Its Geological Implication 被引量:91
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作者 GENG Yuansheng LIU Fulai YANG Chonghui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第6期819-833,共15页
By using the SHRIMP U-Pb and single zircon stepwise evaporation methods, the authors have obtained some results for granitoids from eastern Hebei Province. The Yuhuzhai hyperthene tonalitic granite was formed 2550 Ma ... By using the SHRIMP U-Pb and single zircon stepwise evaporation methods, the authors have obtained some results for granitoids from eastern Hebei Province. The Yuhuzhai hyperthene tonalitic granite was formed 2550 Ma ago, the Qingyangshu gabbroic gneiss 2536 Ma, the Yinmahe granodioritic gneiss near Lücao, Lulong County, 2533 Ma, the gabbro-dioritic gneiss near Longwan, Qianxi County, 2518-2515 Ma, the Qiuhuayu trondjemitic gneiss at Zunhua 2515 Ma, the Xiaoguanzhuang tonalitic gneiss at Zunhua 2495 Ma, and the Cuizhangzi gneiss in Qianxi County 2492 Ma. These geochronilogical data demonstrate that, though diverse in composition, type and origin, the granitic gneisses in eastern Hebei Province were emplaced and crystallized in a rather short period of magmatic activity. The formation of such a great amount of gneisses in this small time gap suggests that it was a critical crust accretion stage at the end of Neoarchean. The fact that granitoids of various types occurred at the same time implies a large-scale underplating (mantle plume) activity, which was then responsible for the crust accretion. 展开更多
关键词 ORTHOGNEISS magmatic event NEOARCHEAN zircon age eastern Hebei Province
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青藏高原动物地理区的地位和东部界线问题 被引量:59
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作者 陈宜瑜 陈毅峰 刘焕章 《水生生物学报》 CAS CSCD 北大核心 1996年第2期97-103,共7页
本文从历史时空的角度分析了青藏高原地区发生的鱼类区系的变化过程,和高原鱼类区系演化的相对独立性,认为这一鱼类区系的分化直接反映了高原隆升事件,并应当在动物地理区划上得到客观反映,即将青藏高原作为一个独立的区划单元。由... 本文从历史时空的角度分析了青藏高原地区发生的鱼类区系的变化过程,和高原鱼类区系演化的相对独立性,认为这一鱼类区系的分化直接反映了高原隆升事件,并应当在动物地理区划上得到客观反映,即将青藏高原作为一个独立的区划单元。由于青藏高原的隆升和造成古北区、东洋区分化的第三纪末、第四纪初的全球性气候变冷在时间上相近、波及的范围都巨大,共同促成了欧亚大陆古北区、东洋区和青藏高原区特有类群的分化,作为对这些地史事件反映的青藏高原区、古北区和东洋区,在动物地理区划上应该具有相同的地位.另外,依据高原鱼类的分布范围和青藏高原对非高原鱼类的阻碍作用,讨论了青藏高原的界限及其划分问题。 展开更多
关键词 鱼类区系 青藏高原区 动物地理区划 东部界线
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Zircon SHRIMP Dating for the Weiya Pluton, Eastern Tianshan: Its Geological Implications 被引量:60
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作者 ZHANG Zunzhong GU Lianxing +3 位作者 WU Changzhi LI Weiqiang XI Aihua WANG Shuo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第4期481-490,共10页
The timing of the emplacement of the Weiya pluton remains controversial due to the absence of systematic and precise dating. This paper reports zircon SHRIMP U-Pb dating of different lithologic phases in the Weiya plu... The timing of the emplacement of the Weiya pluton remains controversial due to the absence of systematic and precise dating. This paper reports zircon SHRIMP U-Pb dating of different lithologic phases in the Weiya pluton, and discusses the genesis and tectonic environment. The ages of gabbro, quartz syenite, diorite porphyrite and fine-grained granite are 236±6 Ma, 246±6 Ma, 233±8 Ma and 237±8 Ma, respectively. All these phases were formed in early-middle Indosinian (Triassic) in a post-orogenic environment. In addition to underplating, intraplating of mantle-derived magmas is also a substantial mechanism for magma generation and vertical accretion of the continental crust. Granitoid rocks are important products of vertical continental accretion as underplating evolves gradually to intraplating. The existence of post-orogenic Indosinian granites shows that the middle Tianshan orogenic belt underwent an important tectonic conversion from the Paleo-Asian ocean subduction-collision system to the Paleo-Tethys ocean regime. 展开更多
关键词 SHRIMP dating POST-OROGENIC INDOSINIAN Weiya pluton eastern Tianshan XINJIANG
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Surface Rupture and Co-seismic Displacement Produced by the Ms 8.0 Wenchuan Earthquake of May ^(12)th,2008,Sichuan,China:Eastwards Growth of the Qinghai-Tibet Plateau 被引量:58
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作者 DONG Shuwen ZHANG Yueqiao WU Zhenhan YANG Non MA Yinsheng SHI Wei CHEN Zhengle LONG Changxin AN Meijian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第5期938-948,共11页
An earthquake of Ms 8 struck Wenchuan County, western Sichuan, China, on May 12^th, 2008 and resulted in long surface ruptures (〉300 km). The first-hand observations about the surface ruptures produced by the earth... An earthquake of Ms 8 struck Wenchuan County, western Sichuan, China, on May 12^th, 2008 and resulted in long surface ruptures (〉300 km). The first-hand observations about the surface ruptures produced by the earthquake in the worst-hit areas of Yingxiu, Beichuan and Qingchuan, ascertained that the causative structure of the earthquake was in the central fault zones of the Longmenshan tectonic belt. Average co-seismic vertical displacements along the individual fault of the Yingxiu-Beiehuan rupture zone reach 2.514 m and the cumulative vertical displacements across the central and frontal Longmenshan fault belt is about 5-6 m. The surface rupture strength was reduced from north of Beichuan to Qingchuan County and shows 2-3 m dextral strike-slip component. The Wenchuan thrust-faulting earthquake is a manifestation of eastward growth of the Tibetan Plateau under the action of continuous convergence of the Indian and Eurasian continents. 展开更多
关键词 Ms 8.0 Wenchuan earthquake surface ruptures co-seismic displacement eastern Tibet
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Geochemistry and petrogenesis of Jurassic high Sr/low Y granitoids in eastern China: Constrains on crustal thickness 被引量:54
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作者 Ge, XY Li, XH +1 位作者 Chen, ZG Li, WP 《Chinese Science Bulletin》 SCIE EI CAS 2002年第11期962-968,共7页
The Jurassic high Sr/low Y granitoids in eastern China are characterized by high Sr/Y (27-166) and La/Yb (14-66) ratios, low abundance in Y (6-21μg/g) and Yb (0.5-2.0μg/g), comparable with those of adakites defined ... The Jurassic high Sr/low Y granitoids in eastern China are characterized by high Sr/Y (27-166) and La/Yb (14-66) ratios, low abundance in Y (6-21μg/g) and Yb (0.5-2.0μg/g), comparable with those of adakites defined by Defant et al. Thus, they were recently considered as adakitic rocks by some researchers. Compared with the typical adakites in circum-Pacific margins, however, these high Sr/low Y granitoids have higher K2O (-3.5%) but lower A12O3 (-16.0%) as well as lower Mg#(-38) and δSrN (-1.23) values. Furthermore, they show relatively flat HREE patterns with Y/Yb values of -10 close to the chondritic value. These geochemical characteristics indicate a residue mineral assemblage of hornblende, garnet and plagioclase for these high Sr/low Y granitoids melt. Thus, they were generated by partial melting at 9-13 kbar (30-45 km in depth), similar to the Archaean high-Al TTG rather than the modern adakites. Generation of these high Sr/low Y granitoids cannot be considered as evidence for a thickened 展开更多
关键词 GRANITOIDS ADAKITE TTG JURASSIC eastern China.
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Eastern Asian endemic seed plant genera and their paleogeographic history throughout the Northern Hemisphere 被引量:52
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作者 Steven R. MANCHESTER Zhi-Duan CHEN +1 位作者 An-Ming LU Kazuhiko UEMURA 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第1期1-42,共42页
We review the fossil history of seed plant genera that are now endemic to eastern Asia. Although the majority of eastern Asian endemic genera have no known fossil record at all, 54 genera, or about 9%, are reliably kn... We review the fossil history of seed plant genera that are now endemic to eastern Asia. Although the majority of eastern Asian endemic genera have no known fossil record at all, 54 genera, or about 9%, are reliably known from the fossil record. Most of these are woody (with two exceptions), and most are today either broadly East Asian, or more specifically confined to Sino-Japanese subcategory rather than being endemic to the Sino-Himalayan area. Of the "eastern Asian endemic" genera so far known from the fossil record, the majority formerly occurred in Europe and/or North America, indicating that eastern Asia served as a late Tertiary or Quaternary refugium for taxa. Hence, many of these genera may have originated in other parts of the Northern Hemisphere and expanded their ranges across continents and former sea barriers when tectonic and climatic conditions allowed, leading to their arrival in eastern Asia. Although clear evidence for paleoendemism is provided by the gymnosperms Amentotaxus, Cathaya, Cephalotaxus, Cunninghamia, Cryptomeria, Glyptostrobus, Ginkgo, Keteleeria, Metasequoia, Nothotsuga, Pseudolarix, Sciadopitys, and Taiwania, and the angiosperms Cercidiphyllum, Choerospondias, Corylopsis, Craigia, Cyclocarya, Davidia, Dipelta, Decaisnea, Diplopanax, Dipteronia, Emmenopterys, Eucommia, Euscaphis, Hemiptelea, Hovenia, Koelreuteria, Paulownia, Phellodendron, Platycarya, Pteroceltis, Rehderodendron, Sargentodoxa, Schizophragma, Sinomenium, Tapiscia, Tetracentron, Toricellia, Trapella, and Trochodendron, we cannot rule out the possibility that neoendemism plays an important role especially for herbaceous taxa in the present-day flora of Asia, particularly in the Sino-Himalayan region. In addition to reviewing paleobotanical occurrences from the literature, we document newly recognized fossil occurrences that expand the geographic and stratigraphic ranges previously known for Dipelta, Pteroceltis, and Toricellia. 展开更多
关键词 CRETACEOUS eastern Asia ENDEMIC PALEOBOTANY phytogeography Tertiary.
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东准噶尔卡拉麦里地区黄羊山花岗岩和包体LA-ICP-MS锆石U-Pb测年及地质意义 被引量:48
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作者 杨高学 李永军 +3 位作者 吴宏恩 司国辉 金朝 张永智 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第12期3197-3207,共11页
高精度LA-ICP-MS锆石U-Pb测年结果表明,黄羊山岩浆混合花岗岩加权平均^(206)Pb/^(238)U年龄为311±12Ma,首次获得闪长质微细粒包体加权平均^(206)Pb/^(238)U年龄为300±6Ma,在误差范围内完全一致,均属于晚石炭世,前者代表黄羊... 高精度LA-ICP-MS锆石U-Pb测年结果表明,黄羊山岩浆混合花岗岩加权平均^(206)Pb/^(238)U年龄为311±12Ma,首次获得闪长质微细粒包体加权平均^(206)Pb/^(238)U年龄为300±6Ma,在误差范围内完全一致,均属于晚石炭世,前者代表黄羊山岩浆混合花岗岩成岩年龄,后者代表暗色闪长质微粒包体的形成年龄,表明两者是同时代形成的,属于300Ma前后准噶尔周边地区后碰撞岩浆活动的产物。岩石地球化学研究表明,寄主岩石具有高硅、低铝、贫钙镁、富碱和高分异的特征,寄主岩石、包体和辉绿岩脉成分均落在了混合趋势线上,寄主岩富集Rb和Th等大离子亲石元素及Zr、Hf等高场强元素,亏损Ba、Sr、Ta和Ti等元素,δEu值(为0.01)极低,具有低的^(87)Sr/^(86)Sr初始比值和高正的ε_(Nd)(t)值。黄羊山碱性花岗岩是在后碰撞拉张的构造背景下,幔源岩浆发生底垫作用,由于幔源岩浆底垫作用,下地壳温度升高而熔融形成酸性壳源岩浆,部分幔源岩浆沿着地壳中的深断裂带上涌,发生不同程度壳幔混合形成的,其中闪长质微细粒包体就是基性的幔源岩浆和酸性的壳源岩浆不同程度的混合的记录者,研究区的辉绿岩脉是幔源岩浆直接分异演化的产物。 展开更多
关键词 东准噶尔 卡拉麦里地区 黄羊 混合花岗岩 包体 锆石 U-PB 测年 地质意义 eastern JUNGGAR AREA MAGMA MIXING 幔源岩浆 HOST ROCK HIGH TEMPERATURE 加权平均 辉绿岩脉 底垫作用 PRODUCT MIXING PROCESS
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Unconventional Natural Gas Accumulations in Stacked Deposits:A Discussion of Upper Paleozoic Coal-Bearing Strata in the East Margin of the Ordos Basin, China 被引量:40
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作者 LI Yong YANG Jianghao +3 位作者 PAN Zhejun MENG Shangzhi WANG Kai NIU Xinlei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第1期111-129,共19页
The Upper Paleozoic(Carboniferous to Permian) succession in the east margin of the Ordos Basin in the North China Craton has a potential to contain significant hydrocarbon resources, though attention have been mainly ... The Upper Paleozoic(Carboniferous to Permian) succession in the east margin of the Ordos Basin in the North China Craton has a potential to contain significant hydrocarbon resources, though attention have been mainly attracted for its successful development of coalbed methane(CBM). To improve the previous resource estimates and evaluate the hydrocarbon play possibilities, this study incorporated new discoveries of hydrocarbon units and their stratigraphic relation with source rocks, hydrocarbon migration and trapping configurations. Continuous hydrocarbon accumulation units were identified within the Upper Paleozoic, including the Taiyuan, Shanxi and Xiashihezi formations with great tight gas potential, and the Taiyuan and Shanxi formations also containing shale gas and CBM. Different strata combinations are identified with coal deposition and favour for continuous gas accumulations, including the tidal flat, deltaic and fluvial systems distributed in most of the study areas. Methane was not only generated from the thick coal seams in the Taiyuan and Shanxi formations, but also from shale and dark mudstones. The coal, shale and tight sandstones are proved of remarkable gas content and hydrocarbon indications, and the gas saturation of tight sandstones decreases upward. The stacked deposit combinations vary isochronally in different areas, while the coal seams were developed stably showing good gas sources. Two key stages control the hydrocarbon enrichment, the continuous subsidence from coal forming to Late Triassic and the anomalous paleo-geothermal event happened in Early Cretaceous, as indicated by the fluid inclusions evidence. Extensive areas show good hydrocarbon development potential presently, and more works should be focused on the evaluation and selection of good reservoir combinations. 展开更多
关键词 coal measure GAS transitional SHALE GAS TIGHT sand GAS three gases eastern ORDOS Basin
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Climatic Features Related to Eastern China Summer Rainfalls in the NCAR CCM3 被引量:37
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作者 宇如聪 李薇 +4 位作者 张学洪 刘屹岷 俞永强 刘海龙 周天军 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2000年第4期503-518,共16页
The climatic features associated with the eastern China summer rainfalls (ECSR) are examined in the National Center for Atmospheric Research (NCAR) Community Climate Model Version 3 (CCM3) of the United States of Amer... The climatic features associated with the eastern China summer rainfalls (ECSR) are examined in the National Center for Atmospheric Research (NCAR) Community Climate Model Version 3 (CCM3) of the United States of America, and run with time-evolving sea surface temperature (SST) from September 1978 to August 1993. The CCM3 is shown to capture the salient seasonal features of ECSR. As many other climate models, however, there are some unrealistic projections of ECSR in the CCM3. The most unacceptable one is the erroneously intensified precipitation center on the east periphery of the Tibetan Plateau and its northeastward extension. The artificial strong rainfall center is fairly assessed by comparing with the products of the station rainfall data, Xie and Arkin (1996) rainfall data and the European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis (Gibson et al., 1997). The physical processes involved in the formation of the rainfall center are discussed. The preliminary conclusion reveals that it is the overestimated sensible heating over and around the Tibetan Plateau in the CCM3 that causes the heavy rainfall. The unreal strong surface sensible heating over the southeast and northeast of Tibetan Plateau favors the forming of a powerful subtropical anticyclone over the eastern China. The fake enclosed subtropical anticyclone center makes the moist southwest wind fasten on the east periphery of the Tibetan Plateau and extend to its northeast. In the southeast coast of China, locating on the southeast side of the subtropical anticyclone, the southwest monsoon is decreased and even replaced by northeast wind in some cases. In the CCM3, therefore, the precipitation is exaggerated on the east periphery of the Tibetan Plateau and its northeast extension and is underestimated in the southeast coast of China. Key words Eastern China summer rainfall - Model validation - Subtropical anticyclone - Diabatic heating This study was sponsored by Chinese Academy of Sciences under grant “ Hundred Talents” for “ 展开更多
关键词 eastern China summer rainfall Model validation Subtropical anticyclone Diabatic heating
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Temporal and spatial response of vegetation NDVI to temperature and precipitation in eastern China 被引量:38
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作者 CUI Linli SHI Jun 《Journal of Geographical Sciences》 SCIE CSCD 2010年第2期163-176,共14页
Temporal and spatial response characteristics of vegetation NDVI to the variation of temperature and precipitation in the whole year, spring, summer and autumn was analyzed from April 1998 to March 2008 based on the S... Temporal and spatial response characteristics of vegetation NDVI to the variation of temperature and precipitation in the whole year, spring, summer and autumn was analyzed from April 1998 to March 2008 based on the SPOT VGT-NDVI data and daily temperature and precipitation data from 205 meteorological stations in eastern China. The results indicate that as a whole, the response of vegetation NDVI to the variation of temperature is more pronounced than that of precipitation in eastern China. Vegetation NDVI maximally responds to the variation of temperature with a lag of about 10 days, and it maximally responds to the variation of precipitation with a lag of about 30 days. The response of vegetation NDVI to temperature and precipitation is most pronounced in autumn, and has the longest lag in summer. Spatially, the maximum response of vegetation NDVI to the variation of temperature is more pronounced in the northern and middle parts than in the southern part of eastern China. The maximum response of vegetation NDVI to the variation of precipitation is more pronounced in the northern part than in the middle and southern parts of eastern China. The response of vegetation NDVI to the variation of temperature has longer lag in the northern and southern parts than in the middle part of eastern China. The response of vegetation NDVl to the variation of precipitation has the longest lag in the southern part, and the shortest lag in the northern part of eastern China. The response of vegetation NDVI to the variation of temperature and precipitation in eastern China is mainly consistent with other results, but the lag time of vegetation NDVI to the variation of temperature and precipitation has some differences with those results of the monsoon region of eastern China. 展开更多
关键词 SPOT VGT-NDVI temperature PRECIPITATION response characteristics lag time eastern China
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Spatial Characteristics of Extreme Rainfall over China with Hourly through 24-Hour Accumulation Periods Based on National-Level Hourly Rain Gauge Data 被引量:38
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作者 Yongguang ZHENG Ming XUE +2 位作者 Bo LI Jiong CHEN Zuyu TAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第11期1218-1232,共15页
Hourly rainfall measurements of 1919 national-level meteorological stations from 1981 through 2012 are used to document,for the first time,the climatology of extreme rainfall in hourly through 24-h accumulation period... Hourly rainfall measurements of 1919 national-level meteorological stations from 1981 through 2012 are used to document,for the first time,the climatology of extreme rainfall in hourly through 24-h accumulation periods in China. Rainfall amounts for 3-,6-,12- and 24-h periods at each station are constructed through running accumulation from hourly rainfall data that have been screened by proper quality control procedures. For each station and for each accumulation period,the historical maximum is found,and the corresponding 50-year return values are estimated using generalized extreme value theory. Based on the percentiles of the two types of extreme rainfall values among all the stations,standard thresholds separating Grade I,Grade II and Grade III extreme rainfall are established,which roughly correspond to the 70th and 90th percentiles for each of the accumulation periods. The spatial characteristics of the two types of extreme rainfall are then examined for different accumulation periods. The spatial distributions of extreme rainfall in hourly through 6-h periods are more similar than those of 12- and 24-h periods. Grade III rainfall is mostly found over South China,the western Sichuan Basin,along the southern and eastern coastlines,and in the large river basins and plains. There are similar numbers of stations with Grade III extreme hourly rainfall north and south of 30°N,but the percentage increases to about 70% south of 30°N as the accumulation period increases to 24 hours,reflecting richer moisture and more prolonged rain events in southern China. Potential applications of the extreme rainfall climatology and classification standards are suggested at the end. 展开更多
关键词 extreme rainfall meteorological historical moisture eastern north coastal monsoon seasonal
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Structural pattern of eastern Himalayan syntaxis in Namjagbarwa and its formation process 被引量:37
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作者 ZHANG Jinjiang, Jl Jianqing, ZHONG Dalai, DING Lin & HE Shundong1. Department of Geology, Peking University, Beijing 100871, China 2. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China Correspondence should be addressed to Zhang Jinjiang (email: zhjj@pku.edu.cn) 《Science China Earth Sciences》 SCIE EI CAS 2004年第2期138-150,共13页
The structural pattern of the eastern Himalayan syntaxis in Namjagbarwa consists of two series of structures with different styles. One series compiles the earlier ductile contractional and lateral-slip deformation sy... The structural pattern of the eastern Himalayan syntaxis in Namjagbarwa consists of two series of structures with different styles. One series compiles the earlier ductile contractional and lateral-slip deformation system, formed by nearly north-south shortening within the syntaxis, left-lateral and right-lateral slipping along its western and eastern boundaries respectively. They were possibly produced by the indentation of the Indian continent into Asian continent after India-Asia collision. The peak deformation-metamorphic ages in these structures are 62-60 Ma, ~23 Ma and ~13 Ma. The other series is composed of ductile-brittle normal faults distributing concentrically and dipping toward the outsides of Namjagbarwa Peak. They were probably the collapse structures caused by rapid uplift in a later time and the beginning ages for the normal faulting are about 7.3-6.3 Ma. Keywords Namjagbarwa - eastern Himalayan syntaxis (EHS) - structural pattern - formation process - structural chronology 展开更多
关键词 Namjagbarwa eastern HIMALAYAN syntaxis (EHS) STRUCTURAL pattern formation process STRUCTURAL chronology.
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Exotic origin of the Chinese continental shelf: new insights into the tectonic evolution of the western Pacific and eastern China since the Mesozoic 被引量:34
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作者 Yaoling Niu Yi Liu +15 位作者 Qiqi Xue Fengli Shao Shuo Chen Meng Duan Pengyuan Guo Hongmei Gong Yan Hu Zhenxing Hu Juanjuan Kong Jiyong Li Jinju Liu Pu Sun Wenli Sun Lei Ye Yuanyuan Xiao Yu Zhang 《Science Bulletin》 SCIE EI CAS CSCD 2015年第18期1598-1616,共19页
The effect of paleo-Pacific subduction on the geological evolution of the western Pacific and continental China is likely complex. Nevertheless, our analysis of the distribution of Mesozoic granitoids in the eastern c... The effect of paleo-Pacific subduction on the geological evolution of the western Pacific and continental China is likely complex. Nevertheless, our analysis of the distribution of Mesozoic granitoids in the eastern continental China in space and time has led us to an interesting conclusion: The basement of the continental shelf beneath East and South China Seas may actually be of exotic origin geologically unrelated to the continental lithosphere of eastern China. By accepting the notion that the Jurassic- Cretaceous granitoids in the region are genetically associated with western Pacific subduction and the concept that subduction may cease to continue only if the trench is being jammed, then the termination of the granitoid magmatism throughout the vast region at -88±2 Ma manifests the likelihood of "sudden", or shortly beforehand (- 100 Ma), trench jam of the Mesozoic western Pacific subduction. Trench jam happens if the incoming "plate" or portion of the plate contains a sizeable mass that is too buoyant to subduct. The best candidate for such a buoyant and unsubductable mass is either an oceanic plateau or a micro-continent. We hypothesize that the basement of the Chinese continental shelf represents such an exotic, buoyant and unsubductable mass, rather than seaward extension of the continental lithosphere of eastern China. The locus of the jammed trench (i.e., the suture) is predictably located on the shelf in the vicinity of, and parallel to, the arc-curved coastal line of the southeast continental China. It is not straightforward to locate the locus in the northern section of the East China Sea shelf because of the more recent (〈20 Ma) tectonic re-organization associated with the opening of the Sea of Japan. We predict that the trench jam at - 100 Ma led to the re-orientation of the Pacific plate motion in the course of NNW direction as inferred from the age-progressive Emperor Seamount Chain of Hawaiian hotspot origin (its oldest unsubdued Meiji and Detroit seamounts are -82 M 展开更多
关键词 Mesozoic granitoids in eastern ChinaExotic origin of Chinese continental shelf Trenchjam Transform plate boundary Basal hydrationweakening Lithosphere thinning Cratondestruction Mantle hydrous melting Crustalmelting Plate tectonics South China Sea
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辽宁东部地区森林地被可燃物及其燃烧性的研究 被引量:24
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作者 高国平 王月 《沈阳农业大学学报》 CAS CSCD 2004年第1期24-28,共5页
对辽宁东部山区主要林型及其地被可燃物的种类组成、载量和燃烧性进行了调查研究 ,结果表明该区有8种主要常见林型 ,阔叶树林型下的灌木层、草本层种类数量和盖度明显大于针叶树 ,针叶树凋落物层的盖度大于阔叶树。林型地被可燃物载量... 对辽宁东部山区主要林型及其地被可燃物的种类组成、载量和燃烧性进行了调查研究 ,结果表明该区有8种主要常见林型 ,阔叶树林型下的灌木层、草本层种类数量和盖度明显大于针叶树 ,针叶树凋落物层的盖度大于阔叶树。林型地被可燃物载量变化范围为8.83~26.29t·hm-2。室内测定各种林型凋落物层燃烧性能结果表明 ,针叶树林地被可燃物的燃烧性明显强于阔叶树 ,易燃烧性排序为油松人工纯林、红松人工纯林、赤松人工纯林、栗树人工纯林、天然杂木林、天然栎树林、落叶松人工纯林、栎树矮林。 展开更多
关键词 辽宁 森林 地被可燃物 燃烧性 火灾
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Current management of hepatocellular carcinoma:An Eastern perspective 被引量:27
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作者 Hyung Joon Yim Sang Jun Suh Soon Ho Um 《World Journal of Gastroenterology》 SCIE CAS 2015年第13期3826-3842,共17页
Hepatocellular carcinoma(HCC) is one of the leading causes of cancer death, especially in Eastern areas. With advancements in diagnosis and treatment modalities for HCC, the survival and prognosis of HCC patients are ... Hepatocellular carcinoma(HCC) is one of the leading causes of cancer death, especially in Eastern areas. With advancements in diagnosis and treatment modalities for HCC, the survival and prognosis of HCC patients are improving. However, treatment patterns are not uniform between areas despite efforts to promote a common protocol. Although many hepatologists in Asian countries may adopt the principles of the Barcelona Clinic Liver Cancer staging system, they are also independently making an effort to expand the indications of each treatment and to combine therapies for better outcomes. Several expanded criteria for liver transplantation in HCC have been developed in Asian countries. Living donor liver transplantation is much more commonly performed in these countries than deceased donor liver transplantation, and it may be preceded by other treatments such as the down-staging of tumors. Local ablation therapies are often combined with transarterial chemoembolization( TACE) and the outcome is comparable to that of surgical resection. The indications of TACE are expanding, and there are new types of transarterial therapies. Although data on drug-eluting beads, TACE, and radioembolization in Asian countries are still relatively sparse compared with Western countries, these methods are gradually gaining popularity because of better tolerability and the possibility of improved response rates. Hepatic arterial infusion chemotherapy and radiotherapy are not included in Western guidelines, but are currently being used actively in several Asian countries. For more advanced HCCs, appropriate combinations of TACE, radiotherapy, and sorafenib can be considered, and emerging data indicate improved outcomes of combination therapies compared with single therapies. To include these paradigm shifts into newer treatment guidelines, more studies may be needed, but they are certainly in progress. 展开更多
关键词 HEPATOCELLULAR CARCINOMA eastern Treatment Guideli
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