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《城市化进程中诺邓古村的保护与发展》 被引量:1
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作者 周爱萍 《云南民族大学学报(哲学社会科学版)》 CSSCI 北大核心 2019年第2期2-2,161,共2页
云南民族大学少数民族女性与社会性别研究中心主任杨国才教授等人编著的《城市化进程中诺邓古村的保护与发展》一书,由中国社会科学出版社于2017年12月出版发行,2018年5月第2次印刷。近年来,为推动云南民族大学各学科专业研究生了解云... 云南民族大学少数民族女性与社会性别研究中心主任杨国才教授等人编著的《城市化进程中诺邓古村的保护与发展》一书,由中国社会科学出版社于2017年12月出版发行,2018年5月第2次印刷。近年来,为推动云南民族大学各学科专业研究生了解云南少数民族文化多样性,加强田野调查,促进云南民族大学人文社会科学的理论创新、方法创新和学科创新,及为边疆地区社会问题研究提供平台,每年面向全校师生开班民族学、社会学研究生暑期学校。 展开更多
关键词 次印刷 民族 云南 女性 进程 城市化 大学 中诺
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云南中甸松诺铜多金属矿床成矿特征 被引量:3
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作者 吴俊 董涛 《云南地质》 2013年第4期409-411,共3页
松诺铜多金属矿区地质背景类似于普朗铜矿,异常元素组合与普朗斑岩型铜矿相似,同时均属同一构造岩浆岩带,松诺是寻找"普朗式铜矿"最有利地段。
关键词 三类铜多金属矿 印支期斑岩控矿 三叠系地层赋矿 格咱成矿带 云南甸松
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中环属(Nematoda:Criconemoidea)两个广东新纪录种记述
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作者 张焕欣 陈艳 +2 位作者 何晋 谢辉 徐春玲 《云南农业大学学报(自然科学版)》 CSCD 北大核心 2023年第3期417-422,共6页
【目的】对在广东省农作物上发现的中环属(Mesocriconema Andrásy,1965)种类进行鉴定。【方法】利用传统形态分类学进行形态测计和描述。【结果】鉴定为奥诺中环线虫(M.onoense Luc,1959)和华丽中环线虫[M.ornatum(Risk,1958)Loof&... 【目的】对在广东省农作物上发现的中环属(Mesocriconema Andrásy,1965)种类进行鉴定。【方法】利用传统形态分类学进行形态测计和描述。【结果】鉴定为奥诺中环线虫(M.onoense Luc,1959)和华丽中环线虫[M.ornatum(Risk,1958)Loof&De Grisse,1989]。奥诺中环线虫的鉴别特征为体环纹111~122个,侧区无背腹环纹愈合处;头环纹3个,第1环非常窄,向前倾,亚中唇瓣较小,口针长47.2μm(43.2~53.9μm);阴门口开放,阴道直,受精囊椭圆形,有精子,卵母细胞双行排列;肛门距离阴门约1个体环,阴门到尾端7~10个体环;阴门后虫体圆锥形,末端圆形,多瓣状。华丽中环线虫的鉴别特征为体环纹83~91个,侧区偶见背腹环纹愈合处;头环纹2个,第1环略向内凹,亚中唇瓣大且向前伸出,口针长53.7μm(50.3~57.9μm);阴门口闭合或略开放,阴门前壁形成齿形突起,阴道直,受精囊未见精子,卵母细胞单行或双行排列;肛门距离阴门约0~2个体环,阴门到尾端6~8个体环;阴门后虫体圆锥形,末端圆形,多瓣状。【结论】鉴定的2个种为广东省新纪录,研究结果丰富了中国中环属线虫的种类和种群分布,为今后开展土壤线虫调查和潜在农作物植物线虫危害相关研究提供了重要科学依据。 展开更多
关键词 环属 环线虫 华丽环线虫 地理新纪录 广东
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精彩招标——访中仪万诺进出口公司总经理刘子京
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作者 丁东 《国际融资》 2001年第6期28-30,共3页
面对招标界的激烈竞争,招标公司在调整对策
关键词 招标公司 仪万进出口公司 招标采购
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Two new species of the genus Rhopalopsole (Plecoptera:Leuctridae) from China
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作者 钱昱含 杜予州 《Entomotaxonomia》 CSCD 北大核心 2012年第1期17-21,共5页
Two Rhopalopsole species from China are described as new to science: R. intonsa Qian & Du sp. nov. and R. siculiformis Qian & Du sp. nov..
关键词 Two Rhopalopsole species from China are described as new to science: R. intonsa Qian Du sp.nov. and R. siculiformis Qian Du sp. nov.. Plecoptera Leuctridae Rhopalopsole new species China
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A newly recorded genus and two new species of Stratiomyinae(Diptera:Stratiomyidae) from China
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作者 杨再华 魏濂艨 杨茂发 《Entomotaxonomia》 CSCD 北大核心 2012年第2期296-300,共5页
Two new species, Nothomyia elongoverpa sp. nov. and N. yunnanensis sp. nov., are described from China. Their relationships with related species are discussed and illustrations of the new species are provided. This is ... Two new species, Nothomyia elongoverpa sp. nov. and N. yunnanensis sp. nov., are described from China. Their relationships with related species are discussed and illustrations of the new species are provided. This is the first record of this genus in China. The Guizhou University (GUGC), type specimens are deposited in the Institute of Entomology, 展开更多
关键词 DIPTERA STRATIOMYIDAE Nothomyia new record China
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Research on the Relationship of ENSO and the Frequency of Extreme Precipitation Events in China 被引量:6
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作者 Wei Li Panmao Zhai Jinhui Cai 《Advances in Climate Change Research》 SCIE 2011年第2期101-107,共7页
Based on a daily precipitation observation dataset of 743 stations in China from 1951 2004, the F distribution function is used to calculate the probability distribution of daily precipitation and to define extreme pr... Based on a daily precipitation observation dataset of 743 stations in China from 1951 2004, the F distribution function is used to calculate the probability distribution of daily precipitation and to define extreme precipitation events. Based on this, the relationship of ENSO and the frequency of extreme precipitation events is studied. Results reveal that ENSO events have impact on extreme precipitation events, with different magnitudes at different regions and seasons. In general, during winter and spring, extreme precipitation events occur more often during E1 Nino events than during La Nina events. While during summer and autumn, the opposite is found. The relationship of a two season-lag ENSO and extreme precipitation frequency shows different pattern. Extreme precipitation events occur more often in several regions if an ENSO warm phase happened in the central-eastern tropical Pacific two seasons before. No similar impacts of El Nino and La Nina on the frequency of extreme precipitation events are found. 展开更多
关键词 extreme precipitation F distribution function ENSO NiHo 3.4 sea surface temperature
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Effect of Decadal Changes in Air-Sea Interaction on the Climate Mean State over the Tropical Pacific 被引量:3
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作者 FANG Xiang-Hui ZHENG Fei 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第5期400-405,共6页
Collaboration of interannual variabilities and the climate mean state determines the type of E1 Nifio. Recent studies highlight the impact of a La Nifia-like mean state change, which acts to suppress the convection an... Collaboration of interannual variabilities and the climate mean state determines the type of E1 Nifio. Recent studies highlight the impact of a La Nifia-like mean state change, which acts to suppress the convection and low-level convergence over the central Pacific, on the predominance of central Pacific (CP) E1 Nifio in the most recent decade. However, how interannual variabilities affect the climate mean state has been less thoroughly investigated. Using a linear shallow-water model, the ef- fect of decadal changes of air-sea interaction on the two types of El Nifio and the climate mean state over the tropical Pacific is examined. It is demonstrated that the predominance of the eastem Pacific (EP) and CP E1 Nino is dominated mainly by relationships between anomalous wind stresses and sea surface temperature (SST). Furthermore, changes between air-sea interactions from 1980-98 to 1999-2011 prompted the generation of the La Ninalike pattern, which is similar to the background change in the most recent decade. 展开更多
关键词 air-sea interaction EP E1 Nifio CP E1 Nifio La Nina-like mean state change
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Has the Problem of a Permanent El Nio been Resolved for the Mid-Pliocene? 被引量:1
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作者 ZHANG Zhong-Shi YAN Qing +1 位作者 SU Jing-Zhi GAO Yong-Qi 《Atmospheric and Oceanic Science Letters》 2012年第6期445-448,共4页
The mid-Pliocene, the most recent warm geological period, is thought to be indicative of the fate of the Earth's climate under global warming. Earlier evidence has suggested that permanent El Nio-like conditions e... The mid-Pliocene, the most recent warm geological period, is thought to be indicative of the fate of the Earth's climate under global warming. Earlier evidence has suggested that permanent El Nio-like conditions existed in the mid-Pliocene, though the concept of a permanent El Nio remains controversial. Here, the authors analyzed Nio 3.4 SST in pre-industrial and mid-Pliocene simulations with the low-resolution version of the Norwegian Earth System Model (NorESM-L). The simulated mid-Pliocene Nio3.4 SST, with a smaller standard deviation, indicated that a weaker ENSO existed in the mid-Pliocene relative to the pre-industrial experiment. Compared with earlier modeling studies, our simulations show that the problem of ENSO's standard deviations in the mid-Pliocene remains unresolved, although the mean and the period of ENSO in the mid-Pliocene have been resolved by earlier geological and modeling studies. 展开更多
关键词 mid-Pliocene ENSO permanent El Nio-like conditions
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Prolonged cholestasis after raloxifene and fenofibrate interaction: A case report
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作者 M Isabel Lucena Raúl J Andrade +3 位作者 Luis Vicioso F Jesús González Ketevan Pachkoria Beatriz García-Mu(n|~)oz 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第32期5244-5246,共3页
Assigning causality in drug-induced liver injury is challenging particularly when more than one drug could be responsible. We report a woman on long-term therapy with raloxifen who developed acute cholestasis shortly ... Assigning causality in drug-induced liver injury is challenging particularly when more than one drug could be responsible. We report a woman on long-term therapy with raloxifen who developed acute cholestasis shortly after starting fenofibrate. The picture evolved into chronic cholestasis. We hypothesized that an interaction at the metabolic level could have triggered the presentation of hepatotoxicity after a very short time of exposure to fenofibrate in this patient. The findings of an overexpression of vascular endothelial growth factor in the liver biopsy suggest that angiogenesis might play a role in the persistance of toxic cholestasis. 展开更多
关键词 RALOXIFENE FENOFIBRATE Drug-drug interactions HEPATOTOXICITY Causality assessment
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ECHAM5-Simulated Impacts of Two Types of El Nio on the Winter Precipitation Anomalies in South China 被引量:8
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作者 SU Jing-Zhi ZHANG Ren-He ZHU Cong-Wen 《Atmospheric and Oceanic Science Letters》 CSCD 2013年第5期360-364,共5页
The authors used an atmospheric general circulation model (AGCM) of European Centre Hamburg Model (ECHAM5.4) and investigated the possible impacts of eastern Pacific (EP) and central Pacific (CP) El Ni(n)o o... The authors used an atmospheric general circulation model (AGCM) of European Centre Hamburg Model (ECHAM5.4) and investigated the possible impacts of eastern Pacific (EP) and central Pacific (CP) El Ni(n)o on the winter precipitation anomalies in South China.A composite analysis suggested much more rainfall during the mature phase of EP El Ni(n)o than in the case of CP El Ni(n)o,and their corresponding observed wet centers to be located in the southeast coast and the region to the south of the Yangtze River,respectively.Results obtained on the basis of model-sensitive run imply that the modelsimulated rainfall anomalies agree well with the observation,and the magnitude of simulated rainfall anomalies were found to be reduced when the amplitude of sea surface temperature anomaly (SSTA) forcing of EP and CP El Ni(n)o was cut down.These results imply that the rainfall anomaly in South China is very sensitive not only to the type of El Ni(n)o but also to its intensity. 展开更多
关键词 eastern/central Pacific El Ni(n)o precipitation ECHAM5 South China
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Asymmetric Response of the South China Sea SST to El Nio and La Nia 被引量:3
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作者 HUANG Zhuo DU Yan +1 位作者 WU Yanling XU Haiming 《Journal of Ocean University of China》 SCIE CAS 2013年第2期272-278,共7页
The interannual variability of the sea surface temperature (SST) in the South China Sea (SCS) is investigated according to its relationship with E1 Nifio/La Nifia (EN/LN) using monthly products from ICOADS. The ... The interannual variability of the sea surface temperature (SST) in the South China Sea (SCS) is investigated according to its relationship with E1 Nifio/La Nifia (EN/LN) using monthly products from ICOADS. The SCS SST bears two peaks associated with EN/LN and shows the asymmetric features. Coinciding with the mature phase of EN/LN, the first SST warming/cooling peaks in December(0)-February(1) (DJF(1)) and centers in the southern part. The major difference is in the amplitude associated with the strength of EN/LN. However, the SCS SST anomaly shows distinct difference after the mature phase of EN/LN. The EN SST warm- ing develops a mid-summer peak in June-August(1) (JJA(1)) and persists up to September-October(l), with the same amplitude of the first warming peak. Whereas the LN SST cooling peaks in May(l), it decays slowly until the end of the year, with amplitude much weaker. Comparing with SST and atmospheric circulations, the weak response and early termination of the second cooling is due to the failure of the cyclonic wind anomalies to develop in the northwest Pacific during JJA(1). 展开更多
关键词 SST South China Sea (SCS) E1 Nifio/La Nifia asymmetric responses interannual variability
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Estimates of Reynolds Stress and TKE Production in the Seasonally Stratified East China Sea
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作者 YANG Wei ZHAO Liang +4 位作者 XU Peng FENG Jianlong WANG Tao QUAN Qi JIANG Wensheng 《Journal of Ocean University of China》 SCIE CAS 2013年第4期549-556,共8页
During the two cruises in March and July of 2011, the tidal cycling of turbulent properties and the T/S profiles at the same location in seasonally stratified East China Sea (ECS) were measured synchronously by a bo... During the two cruises in March and July of 2011, the tidal cycling of turbulent properties and the T/S profiles at the same location in seasonally stratified East China Sea (ECS) were measured synchronously by a bottom-mounted fast sampling ADCP (acoustic Doppler current profiler) and a RBR CTD (RBR-620) profiler. While focusing on the tide-induced and stratification's impact on mixing, the Reynolds stress and the turbulent kinetic energy (TKE) production rate were calculated using the ‘variance method'. In spring, the features of mixing mainly induced by tides were clear when the water column was well-mixed. Velocity shear and turbulent parameters intensified towards the seabed due to the bottom friction. The components of the velocity shear and the Reynolds stress displayed a dominant semi-diurnal variation related to velocity changes caused by the flood and ebb of M2 tide. Stratification occurred in summer, and the water column showed a strongly stratified pycnocline with a characteristic squared buoy- ancy frequency of N2~ (1-6)x 10 3 S-2 The components of the velocity shear and the Reynolds stress penetrated upwards very fast from the bottom boundary layer to the whole water column in spring, while in summer they only penetrated to the bottom of the pycnocline with a relatively slow propagation speed. In summer, the TKE production within the pycnocline was comparable with and sometimes larger than that in the well-mixed bottom layer under the pycnocline. Considering the associated high velocity shear, it is speculated that the mixing in the pycnocline is a result of the local velocity shear. 展开更多
关键词 TKE production Reynolds stress turbulence STRATIFICATION the East China Sea
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Subtropical Air-Sea Interaction and Development of Central Pacific El Nio 被引量:7
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作者 XIE Ruihuang HUANG Fei REN Hongli 《Journal of Ocean University of China》 SCIE CAS 2013年第2期260-271,共12页
The standard deviation of the central Pacific sea surface temperature anomaly (SSTA) during the period from October to February shows that the central Pacific SSTA variation is primarily due to the occurrence of the... The standard deviation of the central Pacific sea surface temperature anomaly (SSTA) during the period from October to February shows that the central Pacific SSTA variation is primarily due to the occurrence of the Central Pacific E1 Nifio (CP-E1 Nifio) and has a connection with the subtropical air-sea interaction in the northeastern Pacific. After removing the influence of the Eastern Pacific E1 Nifio, an S-EOF analysis is conducted and the leading mode shows a clear seasonal SSTA evolving from the subtropical northeastern Pacific to the tropical central Pacific with a quasi-biennial period. The initial subtropical SSTA is generated by the wind speed decrease and surface heat flux increase due to a north Pacific anomalous cyclone. Such subtropical SSTA can further influence the establishment of the SSTA in the tropical central Pacific via the wind-evaporation-SST (WES) feedback. After established, the central equatorial Pacific SSTA can be strengthened by the zonal advective feedback and thermocline feedback, and develop into CP-E1 Nifio. However, as the thermocline feedback increases the SSTA cooling after the mature phase, the heat flux loss and the reversed zonal advective feedback can cause the phase transition of CP-EI Nifio. Along with the wind stress variability, the recharge (discharge) process occurs in the central (eastern) equatorial Pacific and such a process causes the phase consistency between the thermocline depth and SST anomalies, which presents a contrast to the original recharge/discharge theory. 展开更多
关键词 CP-E1 Nifio subtropical forcing recharge/discharge process phase consistency thermocline depth
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Environmental anomalies in the northeastern East China Sea during the last 3 000 years:implications for El Nio activity in the Holocene
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作者 常凤鸣 李铁刚 +1 位作者 庄丽华 阎军 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第1期190-200,共11页
To reconstruct the productivity changes for the last 10 500 a in the northeastern East China Sea (ECS), biogenic compounds (such as carbonate, organic carbon and opal), marine micropaleontological fossils (plankt... To reconstruct the productivity changes for the last 10 500 a in the northeastern East China Sea (ECS), biogenic compounds (such as carbonate, organic carbon and opal), marine micropaleontological fossils (planktonic foraminifera, benthic foraminifera, radiolarian and silicoflagellate) and the compositional characters of benthic foraminifera fauna analyses were carried out on a sediment core DOC082 obtained from the western slope of Okinawa Trough (29°13.93′N, 128°08.53′E; 1 128 m water depth). The long-term changes of biogenic and micropaleontological proxies display some similarities through the last 10 500 a, which show three different phases: lower values are recorded during the early and middle ttolocene (before about 4 000 a BP), followed by an abrupt and remarkable increase at about 4 000 a BP, the late Holocene (after about 3 000 a BP) is characterized by continuously high values. The multi-proxy data of paleoproductivity and percents of benthic foraminifera genera (Uvigerina and Bulimina) show that during the early and middle Holocene (10 500-4 000 a BP) productivity was relatively low with a sudden and distinct increase at about 4 000 a BP, and the late Holocene (3 400-0 a BP) is marked by significantly higher productivity. Also, the radiolarian-based sea surface temperature (SST) records reveal a distinct decline in SST in the late Holocene after 3 200 a BP, very different from the early and middle Holocene. For the last 3 000 a, the enhanced biological productivity and distinctly lower SST indicate a major change of oceanographic conditions in the northeastern ECS. These marine environmental anomalies are consistent with other paleoclimatic records for the late Holocene in the Chinese continent and its surrounding regions. After analyzing the mechanisms of modern productivity and SST changes in the northeastern ECS, and based on the climatic anomalies in the Chinese continent and variations in the Kuroshio Current during modern El Nino periods, we suggest that the anomalous environmental conditions in the northeastern ECS may imply intensified El Nino activity during the late Holocene. 展开更多
关键词 late Holocene environmental anomalies E1 Nino northeastern East China Sea PALEOPRODUCTIVITY sea-surface temperature
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From Artemisinin to Antimalarial Drugs:A Role Model of Scientific Collaboration——An Interview with Academician CHEN Kaixian on China's First Nobel Prize in Sciences
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《Bulletin of the Chinese Academy of Sciences》 2015年第4期197-203,共7页
On December 10,pharmocologist TU Youyou from the China Academy of Traditional Chinese Medicine was awarded the 2015Nobel Prize in Physiology or Medicine in Stockholm,"for her discoveries concerning a novel therapy ag... On December 10,pharmocologist TU Youyou from the China Academy of Traditional Chinese Medicine was awarded the 2015Nobel Prize in Physiology or Medicine in Stockholm,"for her discoveries concerning a novel therapy against Malaria".As the first Chinese citizen to receive a Nobel Prize in sciences,she has been under the spotlight and her stories celebrated by many. 展开更多
关键词 Academician Nobel concerning celebrated citizen reporter collaboration honor pioneering disciplines
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Distribution and Elimination of Norfloxacin in Fenneropenaeus chinensis Larvae
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作者 SUN Ming LI Jian +2 位作者 ZHAO Fazhen LI Jitao CHANG Zhiqiang 《Journal of Ocean University of China》 SCIE CAS 2013年第3期397-402,共6页
This study examined the distribution and elimination of Norfloxacin (NFLX) in Fenneropenaeus chinensis ovary and egg and newly hatched larvae. Mature parental shrimp were exposed to 4 or 10mgL-1 NFLX for 2 or 5d. Ov... This study examined the distribution and elimination of Norfloxacin (NFLX) in Fenneropenaeus chinensis ovary and egg and newly hatched larvae. Mature parental shrimp were exposed to 4 or 10mgL-1 NFLX for 2 or 5d. Ovary and eggs of the shrimp were sampled after spawning in order to detect NFLX residue using high-performance liquid chromatography (HPLC). Re- suits showed that NFLX residue accumulated in F. chinensis eggs after the parental exposure, with the highest residue detected in ovary. To examine the fate of NFLX residue in larvae, we further determined the concentration of NFLX residue in F. chinensis eggs and larvae at 4 different developmental stages after 24-h exposure. From the newly metamorphosed larvae (Oh post-metamorphosis, h.p.m), samples were taken at different time intervals to 72 h,p.m. HPLC assay showed that the concentrations of NFLX residue in zoea exposed to 4 and 10mgL-1 NFLX were the highest at 1.5h, i.e., 0.332 and 0.454μgg-1, respectively. At the two NFLX expo- sure levels, the elimination time of half NFLX (half life) in nauplius was 45.36 and 49.85h, respectively, followed by that in zoea (31.68 and 33.13 h), mysis larvae (42.24 and 47.28 h) and postlarvae (24.48 and 30.96 h). Both NFLX exposure levels had a germi- cidal effect. The distribution and elimination of NFLX residue in F. chinensis tissue, eggs and larvae correlated well with the drug exposure level. The disappearance of NFLX residue coincided with the larval growth, and the half-life of NFLX decreased with the larval development. 展开更多
关键词 Fenneropenaeus chinensis larva NFLX HPLC residue analysis
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A Long Lasting and Extensive Drought Event over China in 1876-1878
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作者 De'er Zhang Youye Liang 《Advances in Climate Change Research》 SCIE 2010年第2期91-99,共9页
Between 1876 and 1878 a large-scale drought occurred in China. This is a major meteorological disaster and an extreme climate event despite the cold climate at the end of the Little Ice Age. In this paper the dynamic ... Between 1876 and 1878 a large-scale drought occurred in China. This is a major meteorological disaster and an extreme climate event despite the cold climate at the end of the Little Ice Age. In this paper the dynamic evolution of the occurrence and development of the drought is reproduced on the basis of historical literature records. These were used to calculate the yearly numbers of drought-hit counties and to determine the spatial distribution in addition with concomitant famine, locust plague and pestilence epidemic for each of the three years. The persistent drought disaster spread over 13 provinces with its center in Shaanxi, Henan and Shanxi provinces, where the continuous non-soaking rain period exceeded 340 days. Conclusively, it is more severe than the worst drought (1928-1930) in the 20th century. This drought disaster of 1876-1878 took place in the descending phase of the 11th sunspot activity period and the start of the 12th period. It also happened during a spell of frequent E1 Nino events and corresponds with an extremely strong E1 Nino. 展开更多
关键词 extreme climate event DROUGHT meteorological disaster 1876-1878
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Timing of the granulite facies metamorphism in the Sanggan area,North China craton:zircon U-Pb geochronology 被引量:21
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作者 郭敬辉 翟明国 许荣华 《Science China Earth Sciences》 SCIE EI CAS 2001年第11期1010-1018,共9页
Zircon U-Pb ages are reported for three samples of intrusive rocks in Khondalite series in the Sanggan area, North China craton. The age of meta-granite is dated as 2005±9 Ma, implying that the sedimentary sequen... Zircon U-Pb ages are reported for three samples of intrusive rocks in Khondalite series in the Sanggan area, North China craton. The age of meta-granite is dated as 2005±9 Ma, implying that the sedimentary sequences in Khondalites series formed before 2.0Ga. The age of 1921 ±1Ma for the meta-diorite constrain the age of granulite facies metamorphism younger than this date. The age of 1892±10 Ma for garnet granite is obtained, but the granite crystallization age seems a little younger than the date considering the morphology of zircons. On the basis of these dates and of a concise review of previous age data, it is inferred that the Khondalite series was subjected to granulite facies metamorphism at about 1.87Ga together with tonalitic granulites and HP basic granulites in the Sanggan area. 展开更多
关键词 zircon U-Pb age GRANULITE METAMORPHISM PALEOPROTEROZOIC North China craton
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Lithospheric structure and faulting characteristics of the Helan Mountains and Yinchuan Basin: Results of deep seismic reflection profiling 被引量:10
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作者 LIU BaoJin FENG ShaoYing +4 位作者 JI JiFa WANG ShuaiJun ZHANG JianShi YUAN HongKe YANG GuoJun 《Science China Earth Sciences》 SCIE EI CAS CSCD 2017年第3期589-601,共13页
The Helan Mountains and Yinchuan Basin (HM-YB) are located at the northern end of the North-South tectonic belt, and form an intraplate tectonic deformation zone in the western margin of the North China Craton (NCC... The Helan Mountains and Yinchuan Basin (HM-YB) are located at the northern end of the North-South tectonic belt, and form an intraplate tectonic deformation zone in the western margin of the North China Craton (NCC). The HM-YB has a complicated history of formation and evolution, and is tectonically active at the present day. It has played a dominant role in the complex geological structure and modem earthquake activities of the region. A 135-km-long deep seismic reflection profile across the HM-YB was acquired in early 2014, which provides detailed information of the lithospheric structure and faulting characteristics from near-surface to various depths in the region. The results show that the Moho gradually deepens from east to west in the depth range of 40-48 km along the profile. Significant differences are present in the crustal structure of different tectonic units, including in the distribution of seismic velocities, depths of intra-cmstal discontinuities and undulation pattern of the Moho. The deep seismic reflection profile further reveals distinct structural characteristics on the opposite sides of the Helan Mountains. To the east, The Yellow River fault, the eastern piedmont fault of the Helan Mountains, as well as multiple buried faults within the Yinchuan Basin are all normal faults and still active since the Quaternary. These faults have controlled the Cenozoic sedimentation of the basin, and display a "negative-flower" structure in the profile. To the west, the Bayanhaote fault and the western piedmont fault of the Helan Mountains are east-dipping thrust faults, which caused folding, thrusting, and structural deformation in the Mesozoic stratum of the Helan Mountains uplift zone. A deep-penetrating fault is identified in the western side of the Yinchuan Basin. It has a steep inclination cutting through the middle-lower crust and the Moho, and may be connected to the two groups of faults in the upper crest. This set of deep and shallow fault system consists of both strike-slip, thrust, and normal faults formed over different eras, and provides the key tectonic conditions for the basin-mountains coupling, crustal deformation and crust-mantle interactions in the region. The other important phenomenon revealed from the results of deep seismic reflection profiling is the presence of a strong upper mantle reflection (UMR) at a depth of 82-92 km beneath the HM-YB, indicating the existence of a rapid velocity variation or a velocity discontinuity in that depth range. This is possibly a sign of vertical structural inhomogeneity in the upper mantle of the region. The seismic results presented here provide new clues and observational bases for further study of the deep structure, structural differences among various blocks and the tectonic relationship between deep and shallow processes in the western NCC. 展开更多
关键词 North China Craton Deep seismic reflection profile Lithospheric structure Helan Mountains Yinchuan Basin
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