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Comparative Orotomy of the Archean Superior,North China,and Phanerozoic Altaid Orogenic Systems Architecture
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作者 T.M.KUSKY A.M.C.ŞENGÖR 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第S01期33-35,共3页
Geological maps encode vast amounts of data about rock types,ages,chemistry,orogenic architecture and deep-time history or different tectonic units,yet these are often difficult to extract because of the way different... Geological maps encode vast amounts of data about rock types,ages,chemistry,orogenic architecture and deep-time history or different tectonic units,yet these are often difficult to extract because of the way different geologists portray their results at various scales.To understand orogenesis in 4D,it is essential to uniformly integrate map data,together with geophysical data and deep geochemical mapping(Wang et al.,2023). 展开更多
关键词 ARCHEAN comparative tectonics orotomy Superior craton ALTAIDS north china craton
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Rheological Evidence of the Lithospheric Destruction of the Eastern Block of the North China Craton
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作者 LI Baochun YE Gaofeng +2 位作者 JIN Sheng WEI Wenbo ZHANG Letian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第S01期36-38,共3页
The Eastern Block of the North China Craton(NCC)(Fig.1)has undergone severe lithospheric destruction,with crustal thinning down to 100 km depth(Chen et al.,2009),contrasting sharply with the stable Kalahari and Rae cr... The Eastern Block of the North China Craton(NCC)(Fig.1)has undergone severe lithospheric destruction,with crustal thinning down to 100 km depth(Chen et al.,2009),contrasting sharply with the stable Kalahari and Rae cratons.However,there remains controversy over the destruction pattern(e.g.,Zhu et al.,2017).During the Early Mesozoic,crustal thickening occurred in the Xuhuai and Qinling orogens,followed by lithospheric delamination leading to crustal thinning(Chen et al.,2023).The middle and upper crustal thinning in the Yanshan and Taihang uplifts was induced by mafic magma underplating(Ji et al.,2009). 展开更多
关键词 MAGNETOTELLURICS resistivity viscosity Eastern Block north china Craton
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Assessing climate effects on wheat yield heterogeneity in the North China Plain and evolution from 1960 to 2020
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作者 Yang Han Jinglei Wang Dongmei Qiao 《The Crop Journal》 SCIE CSCD 2024年第6期1791-1800,共10页
This study quantified climate effects on wheat yield heterogeneity in the North China Plain from 1960 to 2020,by integrating the Agricultural Production Systems sIMulator,Optimal Parameters–based Geographical Detecto... This study quantified climate effects on wheat yield heterogeneity in the North China Plain from 1960 to 2020,by integrating the Agricultural Production Systems sIMulator,Optimal Parameters–based Geographical Detector model,and Ensemble Empirical Mode Decomposition model.The factors dominating yield heterogeneity varied by growth stage.For sowing to anthesis,anthesis to maturation,and the entire growth season,minimum temperature,radiation,and vapor pressure deficit has the greatest effect on yield heterogeneity.Interannual periodic oscillations govern the long–term evolution of climate effects on yield heterogeneity from 1960 to 2020. 展开更多
关键词 HETEROGENEITY CLIMATE Wheat production Evolution mechanism north china Plain
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Optimization of inter-seasonal nitrogen allocation increases yield and resource-use efficiency in a water-limited wheat-maize cropping system in the North China Plain
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作者 Xiaonan Zhou Chenghang Du +7 位作者 Haoran Li Zhencai Sun Yifei Chen Zhiqiang Gao Zhigan Zhao Yinghua Zhang Zhimin Wang Ying Liu 《The Crop Journal》 SCIE CSCD 2024年第3期907-914,共8页
Winter wheat–summer maize cropping system in the North China Plain often experiences droughtinduced yield reduction in the wheat season and rainwater and nitrogen(N)fertilizer losses in the maize season.This study ai... Winter wheat–summer maize cropping system in the North China Plain often experiences droughtinduced yield reduction in the wheat season and rainwater and nitrogen(N)fertilizer losses in the maize season.This study aimed to identify an optimal interseasonal water-and N-management strategy to alleviate these losses.Four ratios of allocation of 360 kg N ha^(-1)between the wheat and maize seasons under one-time presowing root-zone irrigation(W0)and additional jointing and anthesis irrigation(W2)in wheat and one irrigation after maize sowing were set as follows:N1(120:240),N2(180:180),N3(240:120)and N4(300:60).The results showed that under W0,the N3 treatment produced the highest annual yield,crop water productivity(WPC),and nitrogen partial factor productivity(PFPN).Increased N allocation in wheat under W0 improved wheat yield without affecting maize yield,as surplus nitrate after wheat harvest was retained in the topsoil layers and available for the subsequent maize.Under W2,annual yield was largest in the N2 treatment.The risk of nitrate leaching increased in W2 when N application rate in wheat exceeded that of the N2 treatment,especially in the wet year.Compared to W2N2,the W0N3 maintained 95.2%grain yield over two years.The WPCwas higher in the W0 treatment than in the W2 treatment.Therefore,following limited total N rate,an appropriate fertilizer N transfer from maize to wheat season had the potential of a“triple win”for high annual yield,WPCand PFPN in a water-limited wheat–maize cropping system. 展开更多
关键词 Cropping system Water-saving irrigation north china Plain Nitrogen optimization Sustainable intensification
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Strong Earthquake Model of North China Craton: A Case of 2023 Mw 5.5 Earthquake in Pingyuan County, Shandong Province, China
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作者 LIU Guanshen LU Renqi +2 位作者 HE Dengfa FANG Lihua ZHANG Yang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第S01期39-40,共2页
North China is one of the high-risk areas for destructive strong earthquakes in China's Mainland, with a history of numerous significant seismic events. On August 6, 2023, an Mw5.5 earthquake struck Pingyuan Count... North China is one of the high-risk areas for destructive strong earthquakes in China's Mainland, with a history of numerous significant seismic events. On August 6, 2023, an Mw5.5 earthquake struck Pingyuan County, Dezhou City, in Shandong Province, China. This earthquake was the largest in the eastern North China Craton(NCC) since the Tangshan earthquake of 1976. Due to the absence of surface ruptures, the fault responsible for the Pingyuan Mw5.5 earthquake remains unclear. To reveal the subsurface geological structure near the earthquake epicenter, this study utilized highresolution two-dimensional seismic reflection profiles to interpret pre-existing faults. 展开更多
关键词 Pingyuan earthquake seismogenic fault relocation earthquakes north china Craton
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Improved simulation of winter wheat yield in North China Plain by using PRYM-Wheat integrated dry matter distribution coefficient
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作者 Xuan Li Shaowen Wang +6 位作者 Yifan Chen Danwen Zhang Shanshan Yang Jingwen Wang Jiahua Zhang Yun Bai Sha Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1381-1392,共12页
The accurate simulation of regional-scale winter wheat yield is important for national food security and the balance of grain supply and demand in China.Presently,most remote sensing process models use the“biomass... The accurate simulation of regional-scale winter wheat yield is important for national food security and the balance of grain supply and demand in China.Presently,most remote sensing process models use the“biomass×harvest index(HI)”method to simulate regional-scale winter wheat yield.However,spatiotemporal differences in HI contribute to inaccuracies in yield simulation at the regional scale.Time-series dry matter partition coefficients(Fr)can dynamically reflect the dry matter partition of winter wheat.In this study,Fr equations were fitted for each organ of winter wheat using site-scale data.These equations were then coupled into a process-based and remote sensingdriven crop yield model for wheat(PRYM-Wheat)to improve the regional simulation of winter wheat yield over the North China Plain(NCP).The improved PRYM-Wheat model integrated with the fitted Fr equations(PRYM-Wheat-Fr)was validated using data obtained from provincial yearbooks.A 3-year(2000-2002)averaged validation showed that PRYM-Wheat-Fr had a higher coefficient of determination(R^(2)=0.55)and lower root mean square error(RMSE=0.94 t ha^(-1))than PRYM-Wheat with a stable HI(abbreviated as PRYM-Wheat-HI),which had R^(2) and RMSE values of 0.30 and 1.62 t ha^(-1),respectively.The PRYM-Wheat-Fr model also performed better than PRYM-Wheat-HI for simulating yield in verification years(2013-2015).In conclusion,the PRYM-Wheat-Fr model exhibited a better accuracy than the original PRYM-Wheat model,making it a useful tool for the simulation of regional winter wheat yield. 展开更多
关键词 dry matter partition remote sensing model winter wheat yield north china Plain
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Characteristics and main controlling factors of helium resources in the main petroliferous basins of the North China Craton
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作者 Zihan Gao Zhi Chen +5 位作者 Hongyi He Zhaofei Liu Chang Lu Hanyu Wang Yili Luo Ying Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第2期23-33,共11页
At present, the main controlling factors of helium accumulation is one of the key scientific problems restricting the exploration and development of helium reservoir. In this paper, based on the calculation results of... At present, the main controlling factors of helium accumulation is one of the key scientific problems restricting the exploration and development of helium reservoir. In this paper, based on the calculation results of He generation rate and the geochemical characteristics of the produced gas, both the similarities and differences between natural gas and He resources in the Bohai Bay, Ordos and the surrounding Songliao Basin are compared and analyzed, discussing the main controlling factors of helium resources in the three main petroliferous basins of the North China Craton. It is found that the three basins of Bohai Bay, Ordos and Songliao have similar characteristics of source rocks, reservoirs and cap rocks, that's why their methane resource characteristics are essentially the same. The calculated ~4He generation per cubic metamorphic crystalline basement in the three basins is roughly equivalent, which is consistent with the measured He resources, and it is believed that the ~4He of radiogenic from the crust is the main factor controlling the overall He accumulation in the three basins;there is almost no contribution of the mantle-derived CH_4, which suggests that the transport and uplift of mantle-derived ~3He carried by the present-day magmatic activities along the deep-large faults is not the main reason for the mantle-derived ~3He mixing in the basins. Combined with the results of regional volcanic and geophysical studies,it is concluded that under the background of the destruction of North China Craton, magma intrusion carried a large amount of mantle-derived material and formed basic volcanic rocks in the Bohai Bay Basin and Songliao Basin, which replenished mantle-derived ~3He for the interior of the basins, and that strong seismic activities in and around the basins also promoted the upward migration of mantle source ~3He. This study suggests that the tectonic zone with dense volcanic rocks in the Cenozoic era and a high incidence of historical strong earthquakes history may be a potential area for helium resource exploration. 展开更多
关键词 HELIUM Bohai Bay Basin destruction of the north china Craton FAULT Cenozoic volcanic rocks strong earthquake activity
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In situ U-Pb dating and trace elements of magmatic rutile from Mujicun Cu-Mo deposit,North China Craton:Insights into porphyry mineralization
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作者 Fan Yang Jing-wen Mao +4 位作者 Wei-dong Ren Jia-run Tu Gilby Jepson Si-yuan Meng Zhi-min Wang 《China Geology》 CAS CSCD 2024年第4期730-746,共17页
Porphyry Cu(Mo-Au)deposit is one of the most important types of copper deposit and usually formed under magmatic arc-related settings,whilst the Mujicun porphyry Cu-Mo deposit in North China Craton uncommonly generate... Porphyry Cu(Mo-Au)deposit is one of the most important types of copper deposit and usually formed under magmatic arc-related settings,whilst the Mujicun porphyry Cu-Mo deposit in North China Craton uncommonly generated within intra-continental settings.Although previous studies have focused on the age,origin and ore genesis of the Mujicun deposit,the ore-forming age,magma source and tectonic evolution remain controversial.Here,this study targeted rutile(TiO_(2))in the ore-hosting diorite porphyry from the Mujicun Cu-Mo deposit to conduct in situ U-Pb dating and trace element composition studies,with major views to determine the timing and magma evolution and to provide new insights into porphyry Cu-Mo metallogeny.Rutile trace element data show flat-like REE patterns characterized by relatively enrichment LREEs and depleted HREEs,which could be identified as magmatic rutile.Rutile U-Pb dating yields lower intercept ages of 139.3–138.4 Ma,interpreted as post magmatic cooling timing below about 500℃,which are consistent or slightly postdate with the published zircon U-Pb ages of diorite porphyry(144.1–141.7 Ma)and skarn(146.2 Ma;139.9 Ma)as well as the molybdenite Re-Os ages of molybdenum ores(144.8–140.0 Ma).Given that the overlap between the closure temperature of rutile U-Pb system and ore-forming temperature of the Mujicun deposit,this study suggests that the ore-forming ages of the Mujicun deposit can be constrained at 139.3–138.4 Ma,with temporal links to the late large-scale granitic magmatism at 138–126 Ma in the Taihang Orogen.Based on the Mg and Al contents in rutile,the magma of ore-hosting diorite porphyry was suggested to be derived from crust-mantle mixing components.In conjunction with previous studies in Taihang Orogen,this study proposes that the far-field effect and the rollback of the subducting Paleo-Pacific slab triggered lithospheric extension,asthenosphere upwelling,crust-mantle interaction and thermo-mechanical erosion,which jointly facilitated the formation of dioritic magmas during the Early Cretaceous.Subsequently,the dioritic magmas carrying crust-mantle mixing metallic materials were emplaced and precipitated at shallow positions along NNE-trending ore-controlling faults,eventually resulting in the formation of the Mujicun Cu-Mo deposit within an intracontinental extensional setting. 展开更多
关键词 Rutile U-Pb geochronology Rutile geochemistry Intra-continental porphyry mineralization Paleo-Pacific slab subduction Tectonic evolution Magma source Ore-forming age Mujicun Cu-Mo deposit Mineral exploration engineering north china Craton
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Seismogenic model of the 2023 M_(W)5.5 Pingyuan earthquake in North China Plain and its tectonic implications
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作者 Shiguang Wang Libo Han +5 位作者 Junju Xie Liping Fan Xiang Huang Jinmeng Bi Hongfeng Yang Lihua Fang 《Earthquake Science》 2024年第6期499-513,共15页
The 6 August 2023 M_(W)5.5 Pingyuan earthquake is the largest earthquake in the central North China Plain(NCP)over the past two decades.Due to the thick sedimentary cover,no corresponding active faults have been repor... The 6 August 2023 M_(W)5.5 Pingyuan earthquake is the largest earthquake in the central North China Plain(NCP)over the past two decades.Due to the thick sedimentary cover,no corresponding active faults have been reported yet in the epicenter area.Thus,this earthquake presents a unique opportunity to delve into the buried active faults beneath the NCP.By integrating strong ground motion records,high-precision aftershock sequence relocation,and focal mechanism solutions,we gain insights into the seismotectonics of the Pingyuan earthquake.The aftershocks are clustered at depths ranging from 15 to 20 km and delineate a NE-SW trend,consistent with the distribution of ground motion records.A NE-SW nodal plane(226°)of the focal mechanism solutions is also derived from regional waveform inversion,suggesting that the mainshock was dominated by strike-slip motion with minor normal faulting component.Integrating regional geological data,we propose that an unrecognized fault between the NE-SW trending Gaotang and Lingxian-Yangxin faults is the seismogenic fault of this event.Based on the S-wave velocity structure beneath the NCP,this fault probably extends into the lower crust with a high angle.Considering the tectonic regime and stress state,we speculate that the interplay of shear strain between the Amurian and South China blocks and the hot upwelling magma from the subducted paleo Pacific flat slab significantly contributed to the generation of the Pingyuan earthquake. 展开更多
关键词 Pingyuan earthquake aftershock relocation focal mechanism S-wave velocity structure north china Plain
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Experimental study on reactions between alkaline basaltic melt and orthopyroxenes: constraints on the evolution of lithospheric mantle in the North China Craton
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作者 Hanqi He Mingliang Wang Hongfeng Tang 《Acta Geochimica》 EI CAS CSCD 2024年第2期354-365,共12页
The experimental results of the reactions between an alkaline basaltic melt and mantle orthopyroxenes under high-temperature and high-pressure conditions of 1300–1400℃ and 2.0–3.0 GPa using a six-anvil apparatus ar... The experimental results of the reactions between an alkaline basaltic melt and mantle orthopyroxenes under high-temperature and high-pressure conditions of 1300–1400℃ and 2.0–3.0 GPa using a six-anvil apparatus are reported in this paper.The reactions are proposed to simulate the interactions between melts from the asthenospheric mantle and the lithospheric mantle.The starting melt in the experiments was made from the alkaline basalt occurring in Fuxin,Liaoning Province,and the orthopyroxenes were separated from the mantle xenoliths in Damaping,Hebei Province.The results show that clinopyroxenes were formed in all the reactions between the alkaline basaltic melt and orthopyroxenes under the studied P–T conditions.The formation of clinopyroxene in the reaction zone is mainly controlled by dissolution–crystallization,and the chemical compositions of the reacted melt are primarily infl uenced by the diff usion eff ect.Temperature is the most important parameter controlling the reactions between the melt and orthopyroxenes,which has a direct impact on the melting of orthopyroxenes and the diff usion of chemical components in the melt.Temperature also directly controls the chemical compositions of the newly formed clinopyroxenes in the reaction zone and the reacted melt.The formation of clinopyroxenes from the reactions between the alkaline basaltic melt and orthopyroxenes can result in an increase of CaO and Al_(2)O_(3) contents in the rocks containing this mineral.Therefore,the reactions between the alkaline basaltic melt from the asthenospheric mantle and orthopyroxenes from the lithospheric mantle can lead to the evolution of lithospheric mantle in the North China Craton from refractory to fertile with relatively high CaO and Al 2 O 3 contents.In addition,the reacted melts in some runs were transformed from the starting alkaline basaltic into tholeiitic after reactions,indicating that tholeiitic magma could be generated from alkaline basaltic one via reactions between the latter and orthopyroxene. 展开更多
关键词 Alkaline basaltic melt ORTHOPYROXENE Melt–mineral reaction High-temperature and high-pressure experiment Genesis of basalt Evolution of lithospheric mantle in the north china Craton
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Neotectonics around the Ordos Block,North China
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作者 SHI Wei DONG Shuwen HU Jianmin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第S01期62-66,共5页
The Eurasian continent was subject to multiphase intensive intracontinental deformation in the Cenozoic(Fig.1A).However,its Cenozoic intra-continental deformation process and the driving force has long been disputed,w... The Eurasian continent was subject to multiphase intensive intracontinental deformation in the Cenozoic(Fig.1A).However,its Cenozoic intra-continental deformation process and the driving force has long been disputed,which is only associated with the Indo-Asian collision(Molnar and Tapponnier,1975;Jolivet et al.,1990;Tapponnier et al.,2001;Yin,2010;Xu et al.,2013;Zhao et al.,2016),is caused by the Pacific-Asian collision(Cui,1997;Schellart and Lister,2005;Fan et al.,2019),or is connected with a combined effect of the Indo-Asian collision and the Pacific-Eurasia convergence(Ren et al.,2002;Li et al.,2013;Shi et al.,2015;Liu et al.,2019). 展开更多
关键词 neotectonics faulted basin intracontinental deformation Indo-Asian collision Ordos Block Pacific-Asian collision north china
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Microdiamonds in Alkalic Dolerites from the North China Craton
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作者 Yitao Cai Fei Liu +2 位作者 Kan Li Long Li Jingsui Yang 《宝石和宝石学杂志(中英文)》 CAS 2024年第S01期40-42,共3页
Diamonds on the Earth mainly occur in volcanic rocks such as kimberlites and lamproites^([1-8]),but can also be found in ultrahigh-pressure metamorphic rocks^([9-10]),meteorites^([11])and alluvial deposits^([12]).In r... Diamonds on the Earth mainly occur in volcanic rocks such as kimberlites and lamproites^([1-8]),but can also be found in ultrahigh-pressure metamorphic rocks^([9-10]),meteorites^([11])and alluvial deposits^([12]).In recent years,diamonds have been recovered from ophiolites^([13-16])and alkalic dolerites^([17-18]).The discovery of ophiolitic diamonds and alkalic dolerites diamonds has drawn significant research interests to explore the origin of this new class of diamond source and to infer the evolution of their hosting rocks[^(19-21)].This new type of diamond had been initially considered as a result of contamination.However,more and more evidences either directly or indirectly demonstrate that these diamonds are of natural origin^([16,18,19,22-24]).During a geological survey from 2012 to 2015,the geologists from Nanjing Centre of China Geological Survey discovered a large number of yellow microdiamonds in the Langan area in northern Anhui Province^([18,25-29]).The diamond-bearing rocks of these microdiamonds mainly include dolerite and olivine basalt.From 2016 to 2018,four microdiamonds in basic rocks were recovered again in the prospecting work for primary diamond deposits in the Tashan and Zhangji areas in Xuzhou,which is geographically close to Langan[30].All these microdiamonds are similar in colour and shape to ophiolite type diamonds^([31]),and show different characteristics of kimberlite and lamproite type diamonds.Cai,et al.(2019)reported the petrological characteristics of the diamondiferous rocks^([17,21,30]).In this paper,the morphology,infrared spectrum,and carbon isotope compositions of microdiamonds were analysed and discussed by Fourier infrared spectroscopy and carbon isotope test.The types of microdiamonds found in the North China Craton,the age of mantle occurrence,and the source of carbon isotopes were revealed.In the past,many deposits of macro-diamonds,mostly of TypeⅠa orⅡa,were found in the North China Craton,and they have been extensively studied.Microdiamonds recovered from the alkalic dolerites of the North China Craton were studied by FTIR and carbon isotopic.These diamonds are usually light yellow to yellow,with a few colourless,and cubic,octahedral or rhomboidal dodecahedron,and octahedron in shape.The surface characteristics of diamonds,such as dissolution,can be observed.The overall N concentration is not high,with an average of 173×10^(-6).The infrared spectra show that most of these diamonds are TypeⅠb,and C centres are found at 1344 cm^(-1).Three diamond samples are classified as TypeⅠa/Ⅰb,because of A centres and C centres in these diamonds.Two diamonds are classified as typeⅠaAB because B,B′and A centres are found co-existing.FTIR microscopic measurements from the core to the edge of the TypeⅠaAB diamond suggest a mantle residence time of approximately 550 Ma.The C isotopic analysis reveals that these diamonds are strongly depleted in 13 C.These lowδ^(13) C values of dolerites-hosted diamonds overlap with the lower ends of peridotitic diamonds and metamorphic diamonds,and the upper end of the ophiolitic diamonds.Additionally,the reason for the strong deficitδ^(13) C shown by the carbon isotope should be studied in the future. 展开更多
关键词 microdiamond FTIR carbon isotopic alkalic dolerite north china Craton
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Analysis of Changing Trend of Summer Precipitation in North China
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作者 Wei LIU 《Meteorological and Environmental Research》 2024年第4期15-20,23,共7页
Based on the reanalysis data of the National Center for Environmental Prediction(NCEP)and the precipitation dataset of the U.S.Climate Prediction Center(CPC),the changing trend of summer precipitation in North China(3... Based on the reanalysis data of the National Center for Environmental Prediction(NCEP)and the precipitation dataset of the U.S.Climate Prediction Center(CPC),the changing trend of summer precipitation in North China(35°-40°N,110°-125°E)during 1979-2020 was studied.By calculating the monthly climatic precipitation in North China,it is found that precipitation was mainly distributed from June to August,so the trend of precipitation in North China from June to August was mainly analyzed.Firstly,the five-point moving average of regional mean precipitation in North China from June to August during 1979-2020 was conducted.It is found that the fitting curve of the five-point sliding average was basically consistent with the changing trend of regional precipitation,and it showed a certain upward trend.Secondly,the cumulative anomaly of regional average summer precipitation in North China showed a significant upward trend after 2005,which was similar to the moving average result,indicating that the precipitation in the later period increased compared with the earlier period.The changing trend of summer precipitation in North China in the past 42 years was analyzed,and the results show that precipitation showed a significant increasing trend in most areas of North China,so that regional average precipitation also tended to increase significantly.By comparing the precipitation in the past five years(2016-2020)and the last 36 years(1979-2015),it is found that the increase of summer precipitation in North China was more obvious,so the reasons for the increase in precipitation were further analyzed.Since the occurrence of precipitation requires favorable thermal dynamic conditions,the one-dimensional linear regression of water vapor content at 850 hPa and meridional wind speed was conduced,and it is found that the two variables tended to increase obviously,which was consistent with the increasing trend of precipitation.Seen from both the results of regional average and the spatial distribution of trends,the lower atmospheric water vapor content and wind speed showed a significant positive trend,which led to the increase of summer precipitation.Therefore,it can be concluded that there was a certain changing trend of summer precipitation in North China in the past 42 years,which can provide certain reference for the future forecast of summer precipitation in North China. 展开更多
关键词 north china Summer precipitation Trend analysis
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Response of warm season secondary pollutants to emissions and meteorology in the North China Plain region during 2018-2022
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作者 Yueqi Gao Siyu Wang +7 位作者 Zhaolei Zhang Wenxuan Yu Shuai Wang Shengqiang Zhu Peng Wang Yan Li Yele Sun Hongliang Zhang 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第4期58-64,共7页
自2013年起中国空气质量虽改善,但华北平原(NCP)重污染仍存在且二次污染加剧,而人们对其成因和变化了解有限.本研究利用2018-2022年数据,借助CMAQ模型探讨此污染响应.结果显示,在2018-2022年间,PM_(2.5)浓度显著下降31%-37%,O_(3)和NO_... 自2013年起中国空气质量虽改善,但华北平原(NCP)重污染仍存在且二次污染加剧,而人们对其成因和变化了解有限.本研究利用2018-2022年数据,借助CMAQ模型探讨此污染响应.结果显示,在2018-2022年间,PM_(2.5)浓度显著下降31%-37%,O_(3)和NO_(2)的年下降速率分别为1%和0.5%SIA和SOA也显著减少,每年分别减少9%和6%PM_(2.5)主要因排放减少而下降,而O_(3)则受气象影响而波动.硫酸盐和铵下降的主因是减排,而硝酸盐对气象变化敏感排放和气象变化对SOA的总体减少同样重要,但人为SOA对排放控制敏感生物SOA易受气象变化影响.研究强调了控制人为排放对缓解NCP地区夏季二次污染的重要性. 展开更多
关键词 PM_(2.5) 二次污染物 人为排放 气象 华北平原
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Enhanced rainfall in North China in July 2021:Role of the North Pacific SST gradient
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作者 Zhaoyang Du Lian-Tong Zhou +1 位作者 Kui Liu Xiaoxue Yin 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第2期39-44,共6页
2021年7月,华北地区的降水量突破1980年以来的极值,这与太平洋海温异常的经向梯度相吻合.研究表明,西北太平洋正海温异常与热带中太平洋负海温异常之间的梯度是2021年7月华北地区降水异常偏多的主要原因,该梯度使得西北太平洋反气旋及... 2021年7月,华北地区的降水量突破1980年以来的极值,这与太平洋海温异常的经向梯度相吻合.研究表明,西北太平洋正海温异常与热带中太平洋负海温异常之间的梯度是2021年7月华北地区降水异常偏多的主要原因,该梯度使得西北太平洋反气旋及其南部的气旋北移,汇合的偏东风将大量水汽从海洋输送到华北地区,使得华北地区降水偏多.同时,太平洋海温异常的经向梯度可能在对流层低层触发异常的反向哈德利环流,伴随着南风异常,使得季风环流增强,雨带偏北. 展开更多
关键词 降水 华北地区 海温径向梯度
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Interdecadal changes in the frequency of winter extreme cold events in North China during 1989–2021
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作者 Yali Zhu Fangwu Song Dong Guo 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第4期1-7,共7页
全球变暖背景下,极端天气气候事件的变化受到关注.本文研究发现, 1989-2021年期间,华北地区极端冷日数在2003和2013年发生了年代际变化.极端冷日数先增加后减少. 2003-2012年,西伯利亚-乌拉尔高压偏强,极地西风急流偏弱,有利于冷空气南... 全球变暖背景下,极端天气气候事件的变化受到关注.本文研究发现, 1989-2021年期间,华北地区极端冷日数在2003和2013年发生了年代际变化.极端冷日数先增加后减少. 2003-2012年,西伯利亚-乌拉尔高压偏强,极地西风急流偏弱,有利于冷空气南下入侵华北地区,华北极端冷日数偏多.而在1989-2002年和2013-2021年,情况相反.虽然三个时段华北极端冷日的强度没有显著差异,但与其相联系的冷空气强度变得更强, 2013-2021年冷空气中心区域往西北扩张到了贝加尔湖以西地区. 展开更多
关键词 华北 极端冷事件 西伯利亚–乌拉尔高压 北大西洋涛动 极地急流 东亚西风急流
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Analysis on the Variation Characteristics of Precipitation in North China during Recent 30 Years 被引量:5
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作者 韩军彩 周顺武 +1 位作者 王传辉 岳艳霞 《Meteorological and Environmental Research》 CAS 2010年第10期16-19,24,共5页
Based on the monthly precipitation data from 43 stations in North China from 1979 to 2008,the variation characteristics of precipitation in North China in recent 30 years were analyzed by means of empirical orthogonal... Based on the monthly precipitation data from 43 stations in North China from 1979 to 2008,the variation characteristics of precipitation in North China in recent 30 years were analyzed by means of empirical orthogonal function(EOF)decomposition,Morlet wavelet transform and Mann-Kendall test.The results showed that the spatial distribution of annual and seasonal precipitation was basically identical in North China,while the annual and summer precipitation from the middle of 1980s to the middle of 1990s were obviously more than these in other periods,and there was great annual variation in spring precipitation in 1990s,while autumn precipitation was higher from 1980s to 1990s and then went down after the beginning of 21st century,which was opposite to winter precipitation,namely there was more winter precipitation from 1980s to 1990s and fewer winter precipitation after the beginning of 21st century.In addition,the annual and summer precipitation changed abruptly in 1997,and there was no obvious change in spring precipitation and autumn precipitation,while winter precipitation had an abrupt change in 2000.Meanwhile,wavelet analysis revealed that the variation period of annual and seasonal precipitation was 3-4 years. 展开更多
关键词 north china PRECIPITATION Spatial characteristic Wavelet analysis Abrupt change test china
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Study on the Floating Plant Climatic Adaptation of Undercurrent Constructed Wetland in North China 被引量:3
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作者 赵振国 刘丽 《Agricultural Science & Technology》 CAS 2011年第9期1331-1333,共3页
[Objective] The aim was to choose appropriate floating plant in the wetland in the north China.[Method] Pistia stratiotes L.,Eichhornia crassipes,and Hydrocharis dubia(Bl.) Backer were planted in the aquatic biologi... [Objective] The aim was to choose appropriate floating plant in the wetland in the north China.[Method] Pistia stratiotes L.,Eichhornia crassipes,and Hydrocharis dubia(Bl.) Backer were planted in the aquatic biological pool of constructed subsurface flow wetland system in the reservoir.Through filed investigation,the growth of the three kinds of plants was studied and their adaptability to the northern climate was concluded.[Result] Judging from the growth speed and state of the three kinds of floating plants,the biological characteristic of Pistia stratiotes L.can perfectly adapt the environment in the pool in the reservoir,followed by the Eichhornia crassipes.The growth state of the Hydrocharis dubia(Bl.) Backer was the worst one and it can not adapt to the north environment.[Conclusion] It provided references for the choice of artificial floating plant in the north area. 展开更多
关键词 north china Undercurrent constructed wetland Duckwood Climatic adaptation
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What Happened in the Trans-North China Orogen in the Period 2560-1850 Ma? 被引量:16
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作者 Guochun ZHAO LIU Shuwen +5 位作者 Min SUN LI Sanzhong Simon WILDE Xiaoping XIA Jian ZHANG Yanhong HE 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第6期790-806,共17页
The Trans-North China Orogen (TNCO) was a Paleoproterozic continent-continent collisional belt along which the Eastern and Western Blocks amalgamated to form a coherent North China Craton (NCC). Recent geological,... The Trans-North China Orogen (TNCO) was a Paleoproterozic continent-continent collisional belt along which the Eastern and Western Blocks amalgamated to form a coherent North China Craton (NCC). Recent geological, structural, geochemical and isotopic data show that the orogen was a continental margin or Japan-type arc along the western margin of the Eastern Block, which was separated from the Western Block by an old ocean, with eastward-directed subduction of the oceanic lithosphere beneath the western margin of the Eastern Block. At 2550-2520 Ma, the deep subduction caused partial melting of the medium-lower crust, producing copious granitoid magma that was intruded into the upper levels of the crust to form granitoid plutons in the low- to medium-grade granite-greeustone terranes. At 2530-2520 Ma, subduction of the oceanic lithosphere caused partial melting of the mantle wedge, which led to underplating of mafic magma in the lower crust and widespread mafic and minor felsic volcanism in the arc, forming part of the greenstone assemblages. Extension driven by widespread mafic to felsic volcanism led to the development of back-arc and/or intra-arc basins in the orogen. At 2520-2475 Ma, the subduction caused further partial melting of the lower crust to form large amounts of tonalitic-trondhjemitic-granodioritic (TTG) magmatism. At this time following further extension of back-arc basins, episodic granitoid magmatism occurred, resulting in the emplacement of 2360 Ma, -2250 Ma 2110-21760 Ma and -2050 Ma granites in the orogen. Contemporary volcano-sedimentary rocks developed in the back-arc or intra-are basins. At 2150-1920 Ma, the orogen underwent several extensional events, possibly due to subduction of an oceanic ridge, leading to emplacement of mafic dykes that were subsequently metamorphosed to amphibolites and medium- to high-pressure mafic granulites. At 1880-1820 Ma, the ocean between the Eastern and Western Blocks was completely consumed by subduction, and the dosing of the ocean led to the continent-arc-continent collision, which caused large-scale thrusting and isoclinal folds and transported some of the rocks into the lower crustal levels or upper mantle to form granulites or eclogites. Peak metamorphism was followed by exhumation/uplift, resulting in widespread development of asymmetric folds and symplectic textures in the rocks. 展开更多
关键词 ARCHEAN PALEOPROTEROZOIC SUBDUCTION collision Tram-north china Orogen north china Craton
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Guandishan Granitoids of the Paleoproterozoic Lüliang Metamorphic Complex in the Trans-North China Orogen:SHRIMP Zircon Ages,Petrogenesis and Tectonic Implications 被引量:10
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作者 LIU Shuwen LI Qiugen LIU Chaohui LU Yongjun ZHANG Fan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第3期580-602,共23页
The Paleoproterozoic Liiliang Metamorphic Complex (PLMC) is situated in the middle segment of the western margin of the Trans-North China Orogen (TNCO), North China Craton (NCC). As the most important lithologic... The Paleoproterozoic Liiliang Metamorphic Complex (PLMC) is situated in the middle segment of the western margin of the Trans-North China Orogen (TNCO), North China Craton (NCC). As the most important lithological assemblages in the southern part of the PLMC, Guandishan granitoids consist of early gneissic tonalities, granodiorites and gneissic monzogranites, and younger gneissic to massive monzogranites. Petrochemical features reveal that the early gneissic tonalities and granodiorites belong to the medium-K calc-alkaline series; the early gneissic monzogranites are transitional from high-K calc-alkaline to the shoshonite series; the younger gneissic to massive monzogranites belong to the high-k calc-alkaline series, and all rocks are characterized by right- declined REE patterns and negative Nb, Ta, Sr, P, and Ti anomalies in the primitive mantle normalized spidergrams. SHRIMP zircon U-Pb isotopic dating reveals that the early gneissic tonalities and granodiorites formed at -2.17 Ga, the early gneissic monzogranites at -2.06 Ga, and the younger gneissic to massive monzogranites at -1.84 Ga. Sm-Nd isotopic data show that the early gneissic tonalities and granodiorites have eNd(t) values of +0.48 to -3.19 with Nd-depleted mantle model ages (TDM) of 2.76--2.47 Ga, and early gneissic monzogranites have eNd(t) values of -0.53 to -2.51 with TDM of 2.61--2.43 Ga, and the younger gneissic monzogranites have eNd(t) values of -6.41 to -2.78 with a TDM of 2.69--2.52 Ga.These geochemical and isotopic data indicate that the early gneissic tonalities, granodiorites, and monzogranites were derived from the partial melting of metamorphosed basaltic and pelitic rocks, respectively, in a continental arc setting. The younger gneissic to massive monzogranites were derived by partial melting of metamorphosed greywackes within the continental crust. Combined with previously regional data, we suggest that the Paleoproterozoic granitoid magmatism in the Guandishan granitoids of the PLMC may provide the best geological signature for the complete spectrum of Paleoproterozoic geodynamic processes in the Trans-North China Orogen from oceanic subduction, through collisional orogenesis, to post-orogenic extension and uplift. 展开更多
关键词 Guandishan granitoid petrogenesis SHRIMP zircon geochronology geochemistry Ndisotopes Paleoproterozoic Liiliangshan Complex Trans-north china Orogen north china craton.
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