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Empirical relationship between leaf wax n-alkaneδD and altitude in the Wuyi,Shennongjia and Tianshan Mountains,china:Implications for paleoaltimetry

Empirical relationship between leaf wax n-alkaneδD and alti...

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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： Pan Luo~(a,*),Ping’an Peng~b,Gerd Gleixner~c,Zhuo Zheng~d,Zhonghe Pang~a,Zhongli Ding~a a Key Laboratory of Cenozoic geology and Environment,institute of geology and geophysics,chinese academy of sciences,beijing 100029,china b Guangzhou institute of Geochemistry,chinese academy of sciences,Guangzhou 510640,china c Max Planck institute for biogeochemistry,Jena 07745,Germany d department of Earth sciences,Sun Yat-sen university,Guangzhou 510275,china

Estimating past elevation not only provides evidence for vertical movements of the Earth’s lithosphere,but also increases our understanding of interactions between tectonics,relief and climate in geological history. Development of biomarker hydrogen isotope-based paleoaltimetry techniques that can be applied to a wide range of sample types is therefore of continuing *** we present leaf wax-derived n-alkane 8D (δD) values along three soil altitudinal transects,at different latitudes,in the Wuyi,Shennongjia and Tianshan Mountains in china,to investigateδD gradients and the apparent fractionation between leaf wax and precipitation(ε). We find that soilδD track altitudinal variations of precipitation 8D along the three transects that span variable environment conditions and vertical vegetation *** empiricalδD-altitude relation is therefore established in which the averageδD lapse rate of - 2.27±0.38‰/100 m is suitable for predicting relative paleoelevation change(relative uplift).The application of this empirical gradient is restricted to phases in the mountain uplift stage when the atmospheric circulation had not distinctly changed and to when the climate was not *** empiricalδD-latitude-altitude formula is also calculated:δD = 3.483LAT - 0.0227ALT - 261.5, which gives the preliminary spatial distribution pattern ofδD in modern china. Mean value ofε in the extreme humid Wuyi Mountains is quite negative(-154‰),compared to the humid Shennongjia(-129‰) and the arid(but with abundant summer precipitation) Tianshan Mountains(- 130‰), which suggests aridity or water availability in the growing season is the primary factor controlling soil/ sedimentε.Along the Tianshan transects,values ofε are speculated to be constant with altitude;while along the Wuyi and Shennongjia transects,ε are also constant at the low-mid altitudes,but become slightly more negative at high altitudes which could be attributed to overestimates of precipitation 8D or the vegetation

关键词： leaf wax n-alkane deuterium/hydrogen isotopic ratio inverse altitude effect paleoelevation paleoaltimetry

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Exhumation P-T path of UHP eclogites in the Hong'an area,western Dabie Mountains,china

Exhumation P-T path of UHP eclogites in the Hong'an area,wes...

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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： Jingbo Liu~a,Kai Ye~a,Min Sun~b a State Key Laboratory of Lithosphere Tectonic Evolution,institute of geology and geophysics, chinese academy of sciences,beijing,100029,china b department of Earth sciences,The university of Hong Kong,Pokfulam Rd.,Hong Kong

Four generations of mineral assemblages have been identified in ultrahigh-pressure (UHP) eclogites from the Hong’an area,recording four metamorphic stages of the exhumation trajectory,i.e.,garnet+omphacite+kyanite+ zoisite/epidote+rutile+coesite formed at the UHP stage,garnet+omphacite+paragonite+phengite+amphibole+epidote+quartz at the high-pressure (HP) eclogitic stage,amphibole+epidote+albite-oligoclase+paragonite+quartz at the epidote-amphibolite facies(EA) stage,and actinolite+ albite and pumpellyite+albite+K-feldspar+muscovite+chlorite+margarite+epidote+quartz at the greenschist facies(GS) *** formed at the UHP stage was overgrown by atoll garnet at the HP stage. X-ray images,mineral compositions and compositional profiles indicate that the UHP garnet experienced a variable Fe-Mg modification in response to Fe-Mg exchange between garnet and omphacite prior to the overgrowth of atoll HP garnet.A volume diffusion zone was also observed between the UHP and HP *** following P-T conditions were estimated for these mineral assemblages:480 to 560℃and 2.5 to 2.9 GPa with median values of 520℃and 2.8 GPa at UHP stage,575 to 685℃and 1.6 to 1.9 GPa with the average results of 634±37℃and 1.8±0.06 GPa at the HP stage,500 to 640℃and 0.4 to 1 GPa at the EA stage,and 160 to 320℃and 0.2 to 0.8 GPa at the GS *** Hong’an UHP eclogites experienced a temperature increase of over 100℃from the UHP to HP stages and continued to exhume from the HP to EA stages through a process of approximately isothermal depression,which was followed by a significantly cooling from the EA to GS *** the process of exhumation,UHP eclogites witnessed a series of events involving fluid influx,resulting in the formation of hydrous minerals at different stages. The nature of fluids changed from K-rich at the HP stage to K-poor at the EA stage and then K-rich again at the GS stage.

关键词： UHP metamorphism Eclogite Coesite P-T path Exhumation The Dabie Mountains

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circRNAs deregulation in exosomes derived from bEAS-2b cells is associated with vascular stiffness induced by PM_(2.5)

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Journal of Environmental sciences 2024年第3期137卷 527-539页

作者： Qingping Liu Yaling Zhang bin Han Mengruo Wang Huaifang Hu Jie Ning Wentao Hu Meiyu chen Yaxian Pang Yuanyuan chen Lei bao Yujie Niu Rong Zhang department of Toxicology Hebei Medical UniversityShijiazhuang 050017China State Key Laboratory of Environment Health(Incubation) Key Laboratory of Environment and HealthMinistry of EducationKey Laboratory of Environment and Health(Wuhan)Ministry of Environmental ProtectionSchool of Public HealthTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China china CDC Key Laboratory of Environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijing 100021China Occupational Health and Environmental Health Hebei Medical UniversityShijiazhuang 050017China Hebei Key Laboratory of Environment and Human Health Hebei Medical UniversityShijiazhuang 050017China

As an environmental pollutant,ambient fine particulate matter (PM_(2.5)) was linked to cardiovascular *** molecular mechanisms underlying PM_(2.5)-induced extrapulmonary disease has not been elucidated *** this study the ambient PM_(2.5)exposure mice model we established was to explore adverse effects of vessel and potential ***-term PM_(2.5)exposure caused reduced lung function and vascular stiffness in *** chronic PM_(2.5)induced migration and epithelial-mesenchymal transition (EMT) phenotype in bEAS-2b *** PM_(2.5)treatment,the circRNAs and mRNAs levels of exosomes released by bEAS-2b cells were detected by competing endogenous RNA (ceRNA) array,which contained 1664 differentially expressed circRNAs (DE-circRNAs) and 308 differentially expressed m RNAs (DE-mRNAs).by bioinformatics analysis on host genes of DE-circRNAs,vascular diseases and some pathways related to vascular diseases including focal adhesion,tight junction and adherens junction were ***,ceRNA network was constructed,and DE-mRNAs in ceRNA network were conducted functional enrichment analysis by Ingenuity Pathway Analysis,which indicated that hsa_circ_0012627,hsa_circ_0053261and hsa_circ_0052810 were related to vascular endothelial ***,it was verified experimentally that Exo^(PM2.5)could induce endothelial dysfunction by increased endothelial permeability and decreased relaxation in *** present study,we investigated in-depth knowledge into the molecule events related to PM_(2.5) toxicity and pathogenesis of vascular diseases.

关键词： Fine particulate matter Vascular stiffness Exosome ceRNA microarray Endothelial dysfunction

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Modeling the relationship between E×b vertical drift and the time rate of change of hmF2(ΔhmF2/Δt)over the magnetic equator

Modeling the relationship between E×B vertical drift and th...

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中国科学院地质与地球物理研究所2008学术年会

作者： Xinan Yue,Weixing Wan,Jiuhou Lei,and Libo Liu 1 institute of geology and geophysics,chinese academy of sciences, beijing,china. 2 Wuhan institute of Physics and Mathematics,chinese academy of sciences,Wuhan,china. 3 Graduate School,chinese academy of sciences,beijing,china. 4 department of Aerospace Engineering sciences,university of Colorado,boulder,Colorado,USA.

[1]A middle and low latitude ionospheric model is used to model the relationship between E×b vertical drift velocity and time rate of change of hmF2(△hmF2/△t) over the magnetic equator.F107(10.7 cm solar radiation flux) is chosen to be equal to 100,150,and 200 to represent low, middle,and high solar activities,respectively,and Ap is equal to 1 to represent quiet geomagnetic *** simulations show that hmF2 derived vertical drifts over the magnetic equator are in good agreement with the E×b vertical drift imposed in the model during 0600-0730 and 1700-2100 *** is consistent with previous comparisons between vertical drift velocities derived from ionosonde,Jicamarca incoherent scatter radar,and AE-E observations ***,the amplitudes of hmF2 derived drift are smaller than the given drift velocities during other local *** disturbed conditions,the variations of hmF2 can be used to determine the occurrence of intense electric field disturbance.

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In-situ U-Pb,Hf and Re-Os isotopic analyses of the Xiangshan Ni-Cu-Co deposit in Eastern Tianshan(Xinjiang),Central Asia Orogenic belt:Constraints on the timing and genesis of the mineralization

In-situ U-Pb,Hf and Re-Os isotopic analyses of the Xiangshan...

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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： Chunming Han~(a,*),Wenjiao Xiao~a,Guochun Zhao~b,Songjian Ao~a,Jien Zhang~a,Wenjun Qu~c,Andao Du~c a institute of geology and geophysics,chinese academy of sciences,beijing 100029,china b department of Earth sciences,The university of Hong Kong,Pokfulam Road,Hong Kong,china c National Research Center of Geoanalysis,beijing,100037,china

The timing and genesis of the major Ni-Cu-Co sulfide deposit in the Xiangshan intrusion have been studied based on newly obtained in-situ U-Pb,Hf and Re-Os isotopic *** SIMS U-Pb zircon ages of the gabbro hosting the Ni-Cu-Co sulfide deposit indicate that the Xiangshan intrusion was emplaced at 279.6±1.1 Ma(95%confidence level,MSWD=1.30,n=15).On the basis of combined geological and geochronological evidence,we suggest that the Xiangshan and other adjacent Ni-Cu deposits were formed in the same *** have low common Os concentrations and high Re/Os ratios,similar to sulphide ores from the Duluth,Sally Malay and Voisey bay *** Re-Os isotopic data from the disseminated and massive ores from the Xiangshan intrusion do not form a single isochron,as they have different initial Os *** Hf and Os isotopic data suggest that the Xiangshan intrusion and associated Ni-Cu-Co mineralization were derived from crustally contaminated mantle *** geochemical data show a tholeiitic affinity and a strong suprasubduction zone signature with negative Nb,Sr,and Ti anomalies similar to N-MORb and *** suggest that the mafic-ultramafic rocks and associated Ni-Cu mineralization of the Eastern Tianshan orogen formed in an Alaska-type subduction zone-arc *** diagnostic features of ridge-trench interaction are present in the chinese East Tianshan orogen(***,adakites,high-Mg andesites,near-trench magmatism,Alaskan-type mafic-ultramafic complexes,high-temperature metamorphic belts that prograde rapidly from low-grade belts,and orogenic gold deposits).The above distinctive rock groups are probably related to the same thermal event,ridge subduction,as in the Cenozoic orogen of Alaska. We suggest that ridge subduction is the most plausible mechanism to provide the necessary *** subduction provides an important promising model for understanding many aspects of the evolution of the chinese Eastern Tianshan orogen,and by inference,t

关键词： Xiangshan intrusion U-Pb geochronology Zircon Re-Os isotopic data

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Geographic boundary and shear wave velocity structure of the“Pacific anomaly”near the core-mantle boundary beneath western Pacific

Geographic boundary and shear wave velocity structure of the...

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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： Yumei He~(a*),Lianxing Wen~b,Tianyu Zheng~a a Seismological Laboratory(SKL-LE),institute of geology and geophysics,chinese academy of sciences, beijing 100029,PR china b department of Geosciences,State university of New York at Stony brook,Stony brook,New York,USA

We determine the geographical boundary and shear-velocity structure of a very-low velocity province at the base of the Earth’s mantle beneath western Pacific(we term it the "Pacific anomaly") based on the waveform modeling and travel time analysis of ScSH-SH *** seismic data are from the china National Digital Seismographic Network,the F-net in Japan,the Global Seismographic Network and several PASSCAL *** observed ScS-SH differential travel-time residuals allow the northwestern geographic boundary of the anomaly to be clearly *** seismic data also suggest that the average shearvelocity reduction inside the anomaly reaches -5%in the lowermost 300km of the *** modeling of the seismic data sampling the edge of the anomaly suggests that the northwestern boundary is best characterized by a shear-velocity model with a velocity jump of about 2%at about 100-145km above the core-mantle boundary and a thin(30-km thick) basal layer with a shear wave velocity reduction of -13%.Stacked seismic data sampling the middle of the anomaly,however,show no evidence for any internal discontinuity with a velocity decrease greater than -2%in the middle of the anomaly. Overall,the seismic data sampling the base of the "Pacific anomaly" can be explained by a negative shear-velocity gradient from 0%to -1%(top) to -13%(bottom) in the lowermost 220 km of the mantle,similar to those of a very-low velocity province beneath the South Atlantic Ocean and the Indian *** a strong negative shear-velocity gradient can be explained by partial melting of a compositional anomaly produced early in the Earth’s history located within a bottom thermal boundary *** travel time data also exhibit small-scale variations inside the anomaly,indicating existence of internal small-scale seismic heterogeneities inside the "Pacific anomaly".

关键词： shear wave velocity structure core-mantle boundary Pacific anomaly

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Study on the mesostructure and mesomechanical characteristics of the soil-rock mixture using digital image processing based finite element method

Study on the mesostructure and mesomechanical characteristic...

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中国科学院地质与地球物理研究所2008学术年会

作者： Wen-jie Xu~(a,*),Zhong-qi Yue~b,Rui-lin Hu~a a Key Laboratory of Engineering Geomechanics,institute of geology and geophysics,chinese academy of sciences,P.O.box 9825,beijing 100029,china b department of Civil Engineering,university of Hong Kong,Hong Kong,china

The soil-rock mixture(SRM) is a kind of inhomogeneous geomaterial,which poses difficulties of in situ sample acquisition and in laboratory geomaterial tests;hence,the study of the SRM’s mechanical properties is still at an early *** this paper,the technique of digital image processing based on the finite element method(DIP-FEM) is introduced to study SRMs in the Leaping Tiger Gorge Reservoir Area,*** on the DIP,the mesostructural characteristics of the SRM are analyzed *** mesostructural concept model of SRM that can actually represent the inhomogeneity of SRM is *** using geometry vectorizaiton transformation, the mesostructural model of SRM in the binary image format has been translated into a vector format(such as DWG or DXF format) which can be imported into the finite element *** using the finite element method,two large-scale direct shear tests of inhomogeneous SRM and homogeneous soil are *** numerical results indicate that the existence of "rock" blocks in SRM will greatly influence the distribution and the failure models of the internal stress *** a result,three kinds of failure models of the SRM are put forward.

关键词： Soil-rock mixture(SRM) Digital image processing based finite element method(DIP-FEM) Mesostructure Direct shear test Maximum observed diameter(MOD)

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Estimating compositions of natural ringwoodite in the heavily shocked Grove Mountains 052049 meteorite from Raman spectra

Estimating compositions of natural ringwoodite in the heavil...

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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： L.Feng,~(1,2) Y.Lin,~(1,*) S.Hu,~(1,2) L.Xu,~3 and b.Miao~4 1 Key Laboratory of the Earth’s Deep Interior,institute of geology and geophysics,chinese academy of sciences,beijing 100029,china 2 Graduate School of chinese academy of sciences,beijing 100118,china 3 National Astronomical Observatory,chinese academy of sciences,beijing 100029,china 4 department of Resources and Environmental Engineering,Guilin university of Technology,Guilin 541004,china

A combined Raman spectroscopy and electron probe microanalysis study of the heavily shocked Grove Mountains(GRV) 052049 meteorite revealed the largest chemical fractionation of natural ringwoodite,and composition-dependent variation of the intensities and/or wavenumbers of Raman *** Fa content[atomic ratio of Fe/(Fe+Mg)]of ringwoodite varying from 27.8 to 81.6 mol%, the peak position of the single band around 290 cm(Sb1),which relates to the SiO translation mode,shifts from 296.0 to 284.6 cm,and one of the doublets around 790 cm(Db1),which relates to the symmetric stretching of SiO,shifts from 796.3 to 782.7 *** addition,the relative intensities of Sb1 and the other band of the doublet around 840 cm(Db2),which relates to asymmetric stretching of SiO,increases with Fa *** on the paired Raman-EPMA data,single-peak and two-peak calibrations were established,which can be used to derive Fa contents of ringwoodite from the Raman *** accuracy of Raman-derived Fa content of ringwoodite is better than±5 mol%.The correlation of Sbl intensity with the Fa content of ringwoodite suggests that the vibration of Sbl is enhanced with the substitution of Mg by *** correlation between Raman spectra and the chemical composition of ringwoodite have potential applications in on-line measurement of high-pressure experiments and in situ mineralogical determination in future planetary explorations.

关键词： Raman spectroscopy ringwoodite chemical compositions shocked meteorite

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Petrology and geochemistry of Zijinshan alkaline intrusive complex in Shanxi Province,western North china Craton:Implication for magma mixing of different sources in an extensional regime

Petrology and geochemistry of Zijinshan alkaline intrusive c...

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中国科学院地质与地球物理研究所2007学术年会

作者： Jifeng Ying~(a,*),Hongfu Zhang~a,Min Sun~b,Yanjie Tang~a, Xinhua Zhou~a,Xiaoming Liu~c a State Key Laboratory of Lithospheric Evolution,institute of geology and geophysics,chinese academy of sciences, P.O.box 9825.beijing 100029,china b department of Earth sciences,The university of Hong Kong,Porkfulam road,Hong Kong,china c department of geology,Northwest university,Xi’an 710069,china

In situ zircon U-Pb ages and Hf isotopic compositions and whole rock geochemical and Sr-Nd-Pb isotopic data are presented for the Zijinshan alkaline intrusive complex from the Shanxi Province,western North china *** rocks dominate the complex with the monzonite occurring in the outermost and pseudoleucite phonolitic breccia in the *** intrusion took place 127 Ma ago with the earliest emplacement of monzonite and the termination of cryptoexplosive pseudoleucite phonolitic *** rocks from this complex show LREE enrichment and HFSE depletion and exhibit enriched to depleted Sr-Nd isotopic *** presence of inherited zircons and enriched Hf isotopic compositions in zircon rims,along with the enriched whole rock Sr-Nd isotopic compositions,indicate that the monzonite was formed through the mixing of lithospheric mantle-derived magma with lower crustderived *** diopside syenite and nepheline-bearing diopside syenite are more depleted than the monzonite in terms of the Sr and Nd isotopes,together with their very high concentrations of LILE,we proposed that they originated from a mixed mantle source of enriched lithospheric mantle and depleted *** nepheline syenite has very low concentrations of MgO,Ni,Cr, suggesting that the magma underwent significant crystal *** most depleted Sr and Nd isotopic compositions ((Sr/Sr)=0.7036-0.7042,ε(t)=-0.2-0.3) among all rock types indicate a great contribution of asthenosphere to the nepheline *** Zijinshan complex and its related crust-mantle interaction occurred in an extensional environment which resulted in continuously asthenospheric *** an extensional environment might have been developed during the post-orogenic stage of the Late Paleozoic amalgamation of North china Craton with Mongolian continents and subsequent Mongol-Okhotsk ocean closure.

关键词： Alkaline complex Crust-mantle interaction Monzonite Nepheline syenite North china Craton

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Precise U-series Dating of Coral Reefs from the South china Sea and the High Sea Level during the Holocene

Precise U-series Dating of Coral Reefs from the South China ...

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中国科学院地质与地球物理研究所2003学术年会

作者： Z.b.Ma+,J.L.Xiao+,X.T.Zhao+,Z.C.Peng++,M.Xia+, G.P.Zhang§,Z.R.Wang++,and Z.S.An+ +institute of geology and geophysics chinese academy of sciences beijing 100029,china ++department of Earth and Space sciences university of Science and Technology of china Hefei 230026,china§institute of Remote Sensing Application chinese academy of sciences beijing 100101,china +institute of Earth Environment chinese academy of sciences Xi’an 710054,china

Coral reefs formed along the southern coast of Hainan Island are one of the most developed Holocene fringing reefs in *** present new precise Th ages of coral reefs collected from the Shuiweiling section in the southern coast of the Hainan Island,Dengloujiao in the southwest of the Leizhou Peninsula,and the chenhang Island and Jinyin Island of the Xisha(Paracel) Islands in the South china *** the high-precision U-series dates and stratigraphic evidence,the timing and character of the sea-level variations of the middle-Holocene in study region are examined: The results show that a flourishing period of coral reef flats in the South china Sea and along its northern coasts appeared in ca.6800 to 5800 a *** is 650 to 950 years earlier than the previous C dates(6150-4850 a).The sea level relative to the nor thern coasts of South china Sea was 3 to 4 m or more higher than that of the present during this period.

关键词： South china Sea Holocene coral reefs TIMS dating sea-level changes

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