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Continental growth and secular evolution:Constraints from U-Pb ages and Hf isotope of detrital zircons in Proterozoic jixian sedimentary section(1.8-0.8 Ga),North china Craton

Continental growth and secular evolution:Constraints from U-...

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中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： ji-Feng Ying,Xin-Hua Zhou~*,Ben-Xun Su,Yan-jie Tang State Key Laboratory of Lithospheric Evolution,institute of geology and geophysics,chinese academy of sciences,beijing 100029,china

In order to understand the Precambrian crustal growth and reworking history of the North china Craton, in situ U-Pb and Lu-Hf isotope analyses were carried out on the detrital zircons from a well-preserved, nearly undeformed Proterozoic sedimentary section with time interval of 1.8-0.8 ***,806 zircons separated from 7 samples collected from each representative stratigraphic unit were measured for U-Pb and Lu-Hf isotopic compositions,of which 430 grains yielded concordant U-Pb *** concordant zircons show three prominent age groups of 1.6-1.8 Ga,1.9-2.2 Ga and 2.3-2.6 *** positive and negativeεHf(t) values were exhibited by zircons from all groups,suggesting both juvenile crust addition and crustal reworkingfor all age *** Hf crustal model ages of zircons reveal that the juvenile materials were continuously added to the crust between 4.0 and 2.0 Ga with a prominent peak at 2.7-3.0 Ga and a less significant peak at 3.1 -3.4 *** juvenile contributions to the newly formed crust decrease stepwise through time,and crustal reworking has dominated over juvenile inputs to the continental crust since 2.6 *** with the detrital zircons from modern rivers running within the North china Craton,the sedimentary rocks contain more older zircons,implying the relatively poor preservation of Archean crustal rocks in modern river sand,and accordingly the weights of Archean crystallizations ages and crustal growth inferred from detrital zircons in modern river are significantly *** integrated studies of detrital zircons from both modern river sands and ancient sedimentary rocks are essential to decipher the early crustal growth history more faithfully.

关键词： Crustal growth Detrital zircon Sedimentary rocks North china Craton

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Identifying and localizing of seismogenic electromagnetic anomalies from data observed by permanent MT stations

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Science china Earth sciences 2024年第5期67卷 1698-1713页

作者： Bing HAN Wenbao HU Guoze ZHAO ji TANG State Key Laboratory of Earthquake Dynamics Institute of GeologyBeijing 100029China Key Laboratory of Exploration Technologies for Oil and Gas Resources of Ministry of Education Yangtze UniversityWuhan 430100China

In this research, an arbitrarily oriented electric dipole at subsurface is used to simulate Seismogenic Electromagnetic(SEM) radiation emanating from a seismic zone during its gestation phase. Analytical synthesis of responses at the Lijiang magnetotelluric(MT) station has revealed that SEM radiation could induce identifiable anomalies in the electromagnetic(EM)spectrum, apparent resistivity and phase within specific frequency bands. Background variations were extracted from long-term observation data of Dali and Lijiang MT stations, enabling the identification of SEM anomalies related to the Yunlong and Yangbi earthquakes. Multiple parameters of dipole sources at subsurface were obtained by applying the Differential Ant Colony Optimization(DACO) algorithm to anomalous data of two stations with multi-frequencies and various response functions. The spatial distribution of these predicted dipoles is predominantly clustered in or around the seismogenic area, with their azimuthal orientation aligning towards the seismogenic fault in general. This study has demonstrated the potential of using subsurface electric dipole simulations for SEM radiation analysis, offering a feasible approach for the prediction and understanding of seismogenic zones.

关键词： MT responses Identifying SEM anomaly Vector electric dipole responses Localizing SEM sources by inversion

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Modelling adsorption of phosphate by soils while the solution concentration decreased with sorption

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Journal of Environmental sciences 1998年第1期10卷 27-32页

作者： Sui Hong jian Research Center of Environment, beijing institute of Management, University of Science and Technology of china, beijing 101408, china Rao ji long Department of geology and geophysics, Yale University

A mechanistic model developed by Barrow (1986) was modified to study the effect of time on adsorption of phosphate by soil when the solution concentration decreased with sorption. The model reproduced the effects of initial solution concentration, and of increasing time on the adsorption by 5 soils. Both the simulated and observed data showed that at low initial solution concentrations, phosphate in the solution decreased rapidly near to zero in a few hours or minutes. And the simulated results suggested that the rate of phosphate sorption by soils under the condition of the solution concentration decreased with sorption is much slower than that the solution concentration remains constant.

关键词： soil phosphate adsorption.

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Characteristics and Formation Mechanism of the geothermal Field in the North china Downfaulted Basin

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Acta geologica Sinica(English Edition) 1990年第3期64卷 329-343页

作者： Chen Moxiang wang jiyang wang ji’an Deng Xiao Yang Shuzhen Xiong Liangping Zhang Juming institute of geology, Academia Sinica, beijing Liu Linqun institute of geology Academia Sinica Beijing

The geothermal field is mainly controlled by the regional tectonic framework characterized by alternationsof uplifted and depressed basement. and exhibits a similar zoned distribution of temperatures. In the upliftedarea the geothermal gradient （G） and terrestrial heat flow value（q） of the Cenozoic sedimentary cover are rela-tively high, with G=3.5-5.0℃/100m and q=63-84mW/m;; whereas in the depressions they are rela-tively low, with G=2.7-3.5℃/100m and q=46-59mW/m;. In the whole region, G=3.58℃/100m and q=61.5±13.4nW/m;, indicating a comparatively high geothermal background and the presence of localgeothermal anomalies. A comparison of the results of mathematical simulation of the geothermal field with themeasured values shows a good agrecment between them. The geothermal difference between various tectonicunits is caused chiefly by the lateral and vertical variation of thermal properties of shallow crustal rocks. Thisphenomenon can be regarded as the result of redistribution of relatively uniform heat flows from the deep crustin the surficial part of the crust in the process of their upward conduction.

关键词： Characteristics and Formation Mechanism of the geothermal Field in the North china Downfaulted Basin

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A brief review of isotopically light Li-a feature of the enriched mantle?

A brief review of isotopically light Li-a feature of the enr...

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中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： Yan-jie Tang~*,Hong-Fu Zhang and ji-Feng Ying State Key Laboratory of Lithospheric Evolution,institute of geology and geophysics, chinese academy of sciences,beijing,china

Lithium isotope geochemistry is increasingly being used to trace deep-earth processes, reflecting the observed large variation of Li isotope ratios in mantle-derived rocks, including peridotite xenoliths associated with ancient *** briefly review the Li isotopic compositions of major geochemical reservoirs,the assumed mechanisms of Li isotopic fractionation,and,in particular,the origins of isotopically light Li in mantle-derived rocks based on the latest developments in Li isotope *** of Li isotope data with existing Sr-Nd isotope ratios reflects the subduction-recycling of ancient oceanic crust and the reappearance of Li in volcanic *** circulation may play an important role in generating the isotopically light-Li component in the mantle-perhaps the enriched mantle end member defined by the Sr-Nd isotopic compositions of oceanic basalts.

关键词： lithium isotope geochemistry fractionation mechanisms peridotite xenoliths review of Li iso topic evolution

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Review of the Lithium Isotope System as a geochemical Tracer

Review of the Lithium Isotope System as a Geochemical Tracer

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中国科学院地质与地球物理研究所2006学术年会

作者： Yan-jie Tang,Hong-Fu Zhang and ji-Feng Ying State Key Laboratory of Lithospheric Evolution,institute of geology and geophysics,chinese academy of sciences,P.O.Box 9825,beijing 100029,china

Li isotopes have many advantageous characteristics as geochemical tracer for a wide range of geological processes,covering fluid/melt-mineral interactions from the Earth’s surface to the *** latest developments in Li isotope geochemistry,in terms of measuring techniques, major geochemical reservoirs,the behaviors during the near-surface weathering and crust/mantle cycling of materials in subducting zone,as well as the signature of convective mantle and controlling factors in Li isotopic fractionation are briefly reviewed in this *** better quantification of partition coefficients(mineral-melt/fiuid) and fractionation factors of Li isotopes (such as temperature and diffusion coefficients),Li isotope system will be a powerful geochemical tracer in future studies.

关键词： Lithium isotope review geochemical tracer

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geochronological framework of Mesozoic volcanic rocks in the Great Xing'an Range,NE china,and their geodynamic implications

Geochronological framework of Mesozoic volcanic rocks in the...

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中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： ji-Feng Ying~*,Xin-Hua Zhou,Lian-Chang Zhang,Fei wang State Key Laboratory of Lithospheric Evolution,institute of geology and geophysics,chinese academy of sciences,P.O.Box 9825,beijing 100029,china

Mesozoic volcanic rocks are widespread throughout the Great Xing’an Range,NE ***,precise data constraining the exact eruption ages are limited,especially for those from the southern Great Xing’an Range,which severely hampers our understanding of the petrogenesis and geodynamics of these *** this paper,we report precise in situ LA-ICPMS zircon U-Pb age measurements for these volcanic *** rocks in the southern Great Xing’an Range were divided into four units from bottom to top,namely,the Manketouebo,Manitu,Baiyingaolao and Meiletu *** previous studies suggested that these volcanic rocks were mainly formed in the Late *** data demonstrate that the Manketouebo formation erupted during Late Jurassic to Early Cretaceous time,whereas the other formations are all of Cretaceous *** southern Great Xing’an Range age dataset,along with recently obtained precise ages for volcanic rocks from the northern Great Xing’an Range indicate that Mesozoic volcanism throughout the Great Xing’an Range commenced in Late Jurassic,but peaked during the Cretaceous. They formed under an extensional tectonic setting which resulted from closure of the Mongol-Okhotsk Ocean and subsequent orogenic *** globally elevated mantle temperature in Cretaceous may provided thermal contributions to the generation of the volcanisms.

关键词： Volcanic rocks geochronology Mesozoic Great Xing’an Range NE china

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Lower crustal xenoliths from Junan,Shandong province and their bearing on the nature of the lower crust beneath the North china Craton

Lower crustal xenoliths from Junan,Shandong province and the...

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中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： ji-Feng Ying~*,Hong-Fu Zhang,Yan-jie Tang State Key Laboratory of Lithospheric Evolution,institute of geology and geophysics,chinese academy of sciences,P.O.Box 9825,beijing 100029,china

geochronological,petrological and geochemical studies were performed on the granulite xenoliths from a Late Cretaceous basaltic breccia dike in Junan,Shandong province,eastern *** xenoliths show close similarities to the Nushan granulite xenoliths from the southern margin of the North china Craton(NCC)and the Archean granulite terrains in terms of mineralogy and bulk rock compositions,but are quite different from the Hanuoba mafic granulite xenoliths from the northern ***-situ zircon U-Pb age and Hf isotopic analyses,together with geochemical data reveal that the protolith of these xenoliths was formed around 2.3 Ga ago,through assimilation-fractional crystallization of a mafic magma.P-T conditions of these xenoliths suggest that the lower crust beneath the Junan region reaches to a depth of 35 km,which agree well with the result deduced from various geophysical *** consistent petrological and seismic Moho depths,the observed velocity structure and calculated velocity of these xenoliths imply the absence of underplating induced crust-mantle transition zone,which was well formed in the northern *** to 40-50 km depth of the lower crust in Early Jurassic,the lower crust beneath Junan extended to a depth of 30 km in Late Cretaceous,suggesting that the lower crust of NCC was significantly thinned during Late Mesozoic.

关键词： Granulite xenoliths Lower crust Petrology geochemistry North china Craton

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Zoned olivine xenocrysts in a late Mesozoic gabbro from the southern Taihang Mountains:implications for old lithospheric mantle beneath the central North china Craton

Zoned olivine xenocrysts in a late Mesozoic gabbro from the ...

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中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： ji-FENG YING~*,HONG-FU ZHANG &YAN-jiE TANG State Key Laboratory of Lithospheric Evolution,institute of geology and geophysics,chinese academy of sciences, P.O.Box 9825,beijing 100029,china

Zoned olivine grains are abundant in the late Mesozoic Shatuo gabbro(southern Taihang Mountains,central North china Craton).Olivine cores are rich in MgO and NiO,rims are rich in FeO and MnO,and both cores and rims have very low CaO *** cores invariably have a high Mg no.(92-94),similar to olivine xenocrysts from Palaeozoic kimberlites in eastern china. The compositional features of these olivines imply that they are xenocrysts rather than phenocrysts, namely,disaggregates of mantle peridotites at the time of *** compositional similarity of olivine cores to xenocrysts from Palaeozoic kimberlites suggests that the lithospheric mantle beneath the central North china Craton is ancient and refractory in nature,and quite different from eastern china,where the mantle is mainly composed of newly accreted materials resulting from large-scale lithospheric removal and *** contrasting features of the lithospheric mantle beneath the eastern and central North china Craton imply that the large-scale lithospheric removal in Phanerozoic times was mainly confined to the eastern North china Craton.

关键词： olivine xenocryst gabbro lithospheric mantle Taihang Mountains

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Discovery of the choristodere Hyphalosaurus baitaigouensis from the Lower Cretaceous jiufotang Formation of western Liaoning,china and its paleobiogeographic significance

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Journal of Palaeogeography 2024年第3期13卷 547-562页

作者： Li-Jun Zhang Shu-An ji Hai-Chun Zhang South china Sea Culture Museum Hainan Tropical Ocean UniversitySanya 572022Hainan ProvinceChina Key Laboratory of Stratigraphy and Paleontology Ministry of Natural ResourcesInstitute of GeologyChinese Academy of Geological SciencesBeijing 100037China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing 210008Jiangsu ProvinceChina

The water-living reptile genus Hyphalosaurus was previously discovered in the Lower Cretaceous Yixian Formation bearing the middle Jehol Biota in western Liaoning,*** complete skeletons of Hyphalosaurus are reported for the first time from the jiufotang Formation bearing the late Jehol Biota at two sites in western *** show the typical characteristics of Hyphalosaurus baitaigouensis in terms of the contact between some cranial bones and the number of cervical and dorsal vertebrae,and therefore are assigned to *** discovery extends the stratigraphic range of this species from the Yixian Formation to the overlying jiufotang *** paper further briefly compares the main characteristics of the two skeletons,summarizes the temporal and spatial distribution of Hyphalosaurus,and discusses the palaeogeographic evolution of western Liaoning at the middle and late Jehol Biota stages based on the aquatic habits of Hyphalosaurus and the geological background of western *** analytical results show that the volcanic downwarped lakes,with distinct geographical divisions in western Liaoning during the deposition of the Yixian Formation,had not completely disappeared till the deposition of the jiufotang *** palaeo-lake in the Fuxin-Yixian Basin underwent the process of generation,expansion and shrinkage during the depositional period of the Yixian Formation and finally merged into a large *** palaeo-Dalinghe River,which connected the main basins in western Liaoning during the depositional period of the jiufotang Formation,was formed simultaneously.

关键词： Western liaoning Jehol biota jiufotang formation Hyphalosaurus baitaigouensis Palaeobiogeography

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