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Cambrian Sequence Stratigraphy and Sea Level Cycles of North China Platform 被引量:2
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作者 Shi Xiaoying Mei Shilong Chen Jianqiang Yang Xinde Department of Geology and Mineral Resources, China University of Geosciences, Beijing 100083 《Journal of Earth Science》 SCIE CAS CSCD 1999年第2期20-28,共9页
The Cambrian of the North China platform consists chiefly of shallow water deposits and shows the sedimentary characters of an epicontinental sea basin. Controlled mainly by global sea level changes and sedimentary in... The Cambrian of the North China platform consists chiefly of shallow water deposits and shows the sedimentary characters of an epicontinental sea basin. Controlled mainly by global sea level changes and sedimentary influx, the depositional sequences all exhibit as composite sequences. From bottom upward, 14 sequences (3rd order) are recognized, which may be grouped into 5 sequence sets and further into 2 mesosequences (2nd order). It is suggested herein that the Cambrian/Ordovician boundary may better be set at the MFS (maximum flooding surface) of the sequence OSq1, above which the conodont Cordylodus lindstroemi occurs. This position is about 40 m above the traditional Cambrian/Ordovician boundary and is within the Yeli Formation. 展开更多
关键词 CAMBRIAN sequence stratigraphy sea level change cycle Cambrian/Ordovician boundary north china platform.
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Microbial Mats in the Mesoproterozoic Carbonates of the North China Platform and Their Potential for Hydrocarbon Generation 被引量:2
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作者 史晓颖 张传恒 +3 位作者 蒋干清 刘娟 王议 刘典波 《Journal of China University of Geosciences》 SCIE CSCD 2008年第5期549-566,共18页
The well-preserved Mesoproterozoic succession in the North China platform consists mainly of three iithological associations including peritidal quartz sandstone, shallow marine and lagoonal dark to black shales, and ... The well-preserved Mesoproterozoic succession in the North China platform consists mainly of three iithological associations including peritidal quartz sandstone, shallow marine and lagoonal dark to black shales, and shallow epeiric carbonates, with a total thickness of up to 8 000 m. In addition to well-documented microplants, macroalgae, and microbial buildups, abundant microbially induced sedimentary structures (MISS) and mat-related sediments have been recognized in these rocks. Intensive microbial mat layers and MISS are especially well preserved in the carbonates of the upper Gaoyuzhuang (高于庄) (ca. 1.5 Ga) and lower Wumishan (雾迷山) (ca. 1.45 Ga) formations, indicating diversified microbial activities and a high organic production. In these petrified biomats, putative microbial fossils (both coccoidal and filamentous) and framboidal pyrites have been identified. The abundance of authigenic carbonate minerals in the host rocks, such as, acicular aragonites, rosette barites, radial siderites, ankerites, and botryoidal carbonate cements, suggests authigenic carbonate precipitation from anaerobic oxidation of methane (AOM) under anoxic/euxinic conditions. Warm climate and anoxic/euxinic conditions in the Mesoproterozoic oceans may have facilitated high microbial productivity and organic burial in sediments. Although authigenic carbonate cements may record carbonate precipitation from anaerobic methane oxidation, gas blister (or dome) structures may indicate gas release from active methanogenesis during shallow burial. Bituminous fragments in mat-related carbonates also provide evidence for hydrocarbon generation. Under proper conditions, the Mesoproterozoic mat-rich carbonates will have the potential for hydrocarbon generation and serve as source rocks. On the basis of petrified biomats, a rough estimation suggests that the Mesoproterozoic carbonates of the North China platform might have a hydrocarbon production potential in the order of 10 ×10^8 t. 展开更多
关键词 Mesoproterozoic carbonate microbially induced sedimentary structure microbial mat anaerobic oxidation of methane hydrocarbon-generation potential north china platform.
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A Study on Sequence Stratigraphy of Mesoproterozoic and Neoproterozoic in Southern North China Platform
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作者 Zhou Hongrui Wang Ziqiang Cui Xinsheng Lei Zhenyu Dong Wenming (Department of Geology and Mineral Resources, China University of Geosciences, Beijing 100083) 《Journal of Earth Science》 SCIE CAS CSCD 1996年第1期13-19,共7页
The southern part of North China platform is one of the regions where the Mesoproterozoic and Neoproterozoic are well developed and is also an ideal place for the study or sequence stratigraphy. The paper deals mainly... The southern part of North China platform is one of the regions where the Mesoproterozoic and Neoproterozoic are well developed and is also an ideal place for the study or sequence stratigraphy. The paper deals mainly with the sequence stratigraphy of Meso-Neoproterozoic in western part of Henan Province. Based on the analysis of sedimentary features, main types and characters of parasequences, integrated with the study of sequence boundary and maximum-flooding surface, the sedimentary systems tracts and sequences are determined. Ruyang Group is divided into 6 third-order sequences Luoyu Group into 2 third-order sequences and Sinian is divided into 3 third-order sequences. Based on the present study, a new scheme about the correlation of Meso-Neoproterozoic Earthen in the region is proposed. 展开更多
关键词 sequence stratigraphy stratigraphic correlation PROTEROZOIC north china platform.
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From Cycles to Sequences:Sequence Stratigraphy and Relative Sea Level Change for the Late Cambrian of the North China Platform 被引量:23
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作者 MEIMingxiang MAYongsheng +1 位作者 DENGJun CHENHuijun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第3期372-383,共12页
In the Late Cambrian, the North China Platform was a typical carbonate ramp platform. The Upper Cambrian of the northern part of the North China Platform is famous for the development of bioherm limestones and storm c... In the Late Cambrian, the North China Platform was a typical carbonate ramp platform. The Upper Cambrian of the northern part of the North China Platform is famous for the development of bioherm limestones and storm calcirudites and can be divided from bottom to top into the Gushan, Changshan and Fengshan formations. In this set of strata, the deep-ramp mudstone and marls and the shallow-ramp packstones and grainstones constitute many carbonate meter-scale cycles of subtidal type. More tidal-flat dolomites are developed in the Upper Cambrian of the southern margin of the North China platform, in which limestone and dolomite beds also constitute many carbonate meter-scale cycles of the peritidal type. These cycles are marked by a variety of litho-facies successions. There are regularly vertical stacking patterns of meter-scale cycles in long-term third-order sequences, which is the key to discerning such sequences. Third- order sequence is marked by a particular sedimentary-facies succession that is the result of the environment-changing process of deepening and shoaling, which is genetically related to third-order sea level changes. Furthermore, four third- order sequences can be grouped in the Upper Cambrian of the North China Platform. The main features of these four third -order sequences in the northern part of the platform can be summarized as follows: firstly, sequence-boundaries are characterized by drowning unconformities; secondly, the sedimentary-facies succession is generally constituted by one from deep-ramp facies to shallow-ramp facies; thirdly, a succession of “CS (?)+HST” (i.e., “condensed section and high- stand system”) forms these four third-order sequences. The chief features for the third-order sequences in the southern part of the North China Platform comprises: more dolomites are developed in the HSTs of third-order sequences and also developed more carbonate meter-scale cycles of peritidal types; the sedimentary-facies succession of the third-order sequences is marked by “shallow ramp-tidal flat”; the sequence boundaries are characterized by exposure punctuated surfaces. According to the changes for the third-order sequences from the north to the south, a regular sequence- stratigraphic framework can be established. From cycles to sequences, the study of sequence stratigraphy from litho-facies successions to sedimentary-facies successions exposes that as follows: meter-scale cycles that are used as the basic working unit actually are litho-facies successions formed by the mechanism of a punctuated aggradational cycle, and third -order sequences that are constituted by regularly vertical stacking patterns of meter-scale cycles are marked by sedimentary-facies successions. On the basis of the changing curve of water depth at each section, the curve of the relative third-order sea level changes in the late Cambrian of the North China Platform can be integrated qualitatively from changing curve of water depth. The correlation of Late Cambrian long-term sea level changes between North China and North America demonstrates that there are not only similarities but also differences, reflecting control of long-term sea level changes both by global eustacy and by regional factors. 展开更多
关键词 squence stratigraphy relative sea level changes Late Cambrian north china platform
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Neoproterozoic Molar-tooth Structure and Constraint of Depositional Facies and Environment in the North China Platform in Jiangsu, Anhui and Liaoning, Eastern China 被引量:10
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作者 LIU Yongqing GAO Linzhi LIU Yanxue 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第4期533-539,共7页
Molar tooth structure (MTS) represented by complex ptygmatical shapes is widely distributed in the Proterozoic of the world. MTS filled by fine, equant sparry calcite (or dolomite) displays an abrupt contact with ... Molar tooth structure (MTS) represented by complex ptygmatical shapes is widely distributed in the Proterozoic of the world. MTS filled by fine, equant sparry calcite (or dolomite) displays an abrupt contact with hosting rocks, which are mainly composed of carbonaceous micrites and fine-grained carbonates with local silts and stormdominated deposits with graded, cross or wave beddings, numerous erosional surfaces and truncated and fills or guttered bases. Occurrence of MTS suggests a result of the constraint of sedimentary facies, and the storm-base in ramp settings is the maximum depth for the formation of MTS. Vertical succession of MTS-bearing carbonates shows a deposition stacked by high-frequency shallow subtidal and peritidal cycles. An individual cyclic MTS-bearing sequence is characterized by thinning, shallowing and dynamic decreasing-upward, and peritidal caps of purple red iron and organic carbonaceous sediments with more complicated shapes of MTS are common on the top of individual MTS-bearing sequences. 展开更多
关键词 north china platform NEOPROTEROZOIC Molar-tooth structure CARBONATE facies and environment
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A Carbon Isotopic Stratigraphic Pattern of the Late Palaeozoic Coals in the North China Platform and Its Palaeoclimatic Implications 被引量:7
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作者 ZHANG Hong SHEN Guanglong HE Zonglian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1999年第1期111-119,共9页
This paper gives the stable carbon isotopic data in coals from the Late Namurian to Kazanian stages in the Serteng Mt., Xishan and Huainan coalfields of the North China Platform. Its stratigraphic pattern shows that s... This paper gives the stable carbon isotopic data in coals from the Late Namurian to Kazanian stages in the Serteng Mt., Xishan and Huainan coalfields of the North China Platform. Its stratigraphic pattern shows that several isotopic shifts are apparent, and the large δ13C negative shifts (approximately 2.5 to 3.0 %%) occurred during the Stephanian, Artinskian and Kazanian are observed in three Permo-Carboniferous coalfields. Those negative shifts are neither related to the coal rank and coal macerals, nor caused by the variety of peat-forming plants. The general decrease in the δ13C values of the Stephanian, Artinskian and Kazanian coals is consistent with an overall decrease in the δ13C values of ambient atmospheric CO2 and/or a relative increase in atmospheric Pco2 during the coal-forming periods. Therefore the authors postulate that the oxidation of peat, and the δ13C-depleted CO2 flux into the atmosphere during the above stages may have contributed to coeval palaeoclimatic warming by way of the greenhouse effect. 展开更多
关键词 carbon isotope COAL PALAEOCLIMATE Late Palaeozoic the north china platform
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Chronology,Geochemistry and Tectonic Settings of the Hadamiao Granodiorite on the Northern Margin of the North China Platform 被引量:3
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作者 HAO Baiwu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第6期1500-1513,共14页
The Hadamiao granodiorite,located on the northern margin of the North China platform and acting as the country rock of gold deposits in the Hadamiao region,was formed in the same age and similar tectonic settings with... The Hadamiao granodiorite,located on the northern margin of the North China platform and acting as the country rock of gold deposits in the Hadamiao region,was formed in the same age and similar tectonic settings with the Hadamiao gold deposit and the large-scale Bilihe gold deposit in the same area.By using the LA-ICP-MS method,the U-Pb age obtained is 267±1.3 Ma,which represents the crystallized age of the granodiorite,and that of the xenolithic zircon is 442.8±5 Ma. Base on the main elements,it exhibits the features of calc-alkaline to high-potassium calc-alkaline series,low silicon,and quasi-aluminous I-type granites,and with high magnesium(Mg~#=0.45-0.57) and high sodium contents(Na_2O/K_2O=0.98-2.29).The SREE values(81.6-110.15 ppm) are relatively low,the fractionations between LREE and HREE are obvious,showing a right-inclined dispersion in the REE distribution diagram.Compared with the primitive mantle,the rock is relatively rich in LREE(La and Ce),LILE(K,Sr,and Th),and intensively depleted in HFSE(Ti,P,Nb and Ta).The ratios of Sr/Y and(La/Yb)_N and the contents of Rb,Nb and Y are relatively low,the Sr values are high (436.35-567.26 ppm),and the Yb contents of most samples are low(1.25-1.8),which indicate the features of typical continental margin arc and adakitic rocks.According to the values ofε_(Nd)(t)(-2.4 to +0.2) and I_(Sr)(0.7028-0.7083),and variations of the La/Sm ratios,the Hadamiao granodiorite was formed from mixing of the thickened molten lower crust and the mantle wedge substances.The rock was related to the southward subduction and accretion of the Paleo-Asia Ocean in the Late Paleozoic, being Late Paleozoic magma of the continental margin arc formed on the basement of the Early Paleozoic accretion complexes,and showing a trend of turning into adakitic rocks,which indicates their great metallogenic(Au) potential. 展开更多
关键词 Hadamiao granodiorite zircon LA-ICP-MS U-Pb dating GEOCHEMISTRY tectonic setting genetic model northern margin of the north china platform
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Rb-Sr Isotopic Chronology of the Au-Bearing Quartz Veins in Gold Deposits in the Eastern Part of North China Platform 被引量:1
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作者 魏俊浩 刘丛强 唐红峰 《Chinese Journal Of Geochemistry》 EI CAS 2002年第4期374-382,共9页
In the eastern part of China there had occurred large\|scale gold mineralization during the Mesozoic, resulting in a large number of important gold ore\|concentrated areas. In this paper we have selected some isotope ... In the eastern part of China there had occurred large\|scale gold mineralization during the Mesozoic, resulting in a large number of important gold ore\|concentrated areas. In this paper we have selected some isotope data (including four gold deposits previously studied and two gold deposits in this work) of Au\|bearing quartz veins of the representative gold deposits in six important gold ore\|concentrated areas in the periphery of the North China Platform and calculated their metallogenic ages using the method of Ludwig (2.90 version). The results show that the representative gold deposits in the six gold ore\|concentrated areas were formed during the Mesozoic. 展开更多
关键词 RB-SR同位素年龄 金矿床 成矿作用 华北平原 中生代
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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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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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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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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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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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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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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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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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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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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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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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Geology and mineralization of the Dongping supergiant alkalic-hosted Au-Te deposit(>100 t Au)in Northern Hebei Province,China:A review
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作者 Shi-min Zhen Da-zhao Wang +2 位作者 Zhong-jian Zha Hai-jun Bai Jiang Wang 《China Geology》 CAS CSCD 2024年第3期533-550,共18页
The Dongping deposit is the largest alkalic-hosted gold deposit in China containing>100 t of Au.This paper presents a new understanding for Dongping ore system,based on the previous studies.The mineralization origi... The Dongping deposit is the largest alkalic-hosted gold deposit in China containing>100 t of Au.This paper presents a new understanding for Dongping ore system,based on the previous studies.The mineralization originally occurred at 400-380 Ma,simultaneous with emplacement of the Shuiquangou alkaline complex,and was overprinted by the hydrothermal activity in the Yanshanian.Isotope compositions of ores indicate metals of the deposit are mainly provided by the Shuiquangou complex.Ore-forming fluids are characterized by increasing oxygen fugacity and decreasing sulfur fugacity,while tellurium fugacity increased in the Stage II-2 and decreased in Stage II-3.These systematic changes are closely related to the processes of mineral precipitation and fluid evolution.Sulfide precipitation from Stage Ⅰ to Stage Ⅱ was triggered by fluid boiling,which leads to the precipitation of Pb-Bi-Te,due to decrement of sulfur fugacity.Condensation of gas phase containing high concentration of H_2Te leads to precipitation of Te-Au-Ag minerals and native tellurium.Based on these hypotheses,this paper present a polyphase metallogenic model as follow.During the Devonian,fluids were released from alkaline magmas,which carried ore-forming materials form the surrounding rocks and precipitate the early ores.During the Jurassic-Cretaceous,fluorine-rich fluids exsolved from highly factionated Shangshuiquan granite,which extracted and concentrated Au from the Shuiquangou complex and the Sanggan Group metamorphic rocks,and finally formed the Dongping gold deposit. 展开更多
关键词 Mineralization and alteration Alkaline intrusion Au deposit Physicochemical conditions Metallogenic model Oxygen fugacity Sulfur fugacity Mechanisms of mineral precipitation Fluid boiling Fluorine-enriched fluid Dongping gold deposit north china Craton Mineral exploration engineering
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