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Ionospheric polarization electric field guiding magnetopause reconnection: A conceptual model of throat aurora

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science China earth sciences 2019年第12期62卷 2099-2105页

作者： Desheng HAN State Key Laboratory of Marine Geology School of Ocean and Earth Science Tongji University

Frequently observed throat auroras have been suggested to be correspondent to indentations on the subsolar magnetopause,but how these indentations can be generated is unknown *** on analyzing the detailed observational features of throat aurora,a conceptual model for generation of throat aurora is *** model suggests that precipitation of a north-south aligned stripy diffuse aurora can lead to an ionospheric conductivity enhancement and thus produce a polarization electric field in dusk-to-dawn direction in the *** mapping to the magnetosphere along closed field lines,this electric field can guide a magnetopause reconnection to develop inward the magnetosphere and result in a throat *** this model can comprehensively explain all the observational results that have been presented up to now,we argue that the assumption of ionospheric polarization electric field affecting magnetopause reconnection should be true and be worthy of further investigations.

关键词： Throat aurora Ionospheric polarization electric field Magnetopause reconnection Magnetosphere-ionosphere coupling Cusp ionosphere

On the influence of season and salinity on the phenology of invertebrates in Australian saline lakes, with special reference to those of the Paroo in the semiarid inland

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Journal of Oceanology and Limnology 2018年第6期36卷 1907-1916页

作者： Brian V.TIMMS Centre for Ecosystem science School of BiologicalEarth and Environmental ScienceUniversity of New South Wales

While the fauna of Australian salt lakes is now well-known, seasonal phenological patterns of invertebrates are not. Two studies on saline lakes in southern Australia suggest the lakes fill in early winter and remain at salinities characteristic for each lake during winter-spring before elevating and drying in summer. The fauna is dominated by crustaceans with few insects and all component species are present most of the time and randomly fluctuating in numbers. Lakes in the southern inland(mainly Lake Eyre) fill in summer, change little in salinity until near drying, and are dominated by crustaceans but have some insects. By contrast temporary salinas in the central inland fill episodically mainly in summer and then their salinity increases steadily as they dry without further rain. Their fauna is also dominated by crustaceans, but with a significant insect component and composition varies though the hydrological cycle. This study reports on an unusual winter fill in two central Paroo lakes and two pools, in which the crustacean fauna is similar to that in summer but insects are delayed till late spring and are not as common as in summer fills. It seems therefore that while insects are more restricted by medium and high salinities than crustaceans, they are also more restricted by cooler temperatures than crustaceans.

关键词： crustaceans aquatic insects rotifers regional fauna biogeography habitat heterogeneity

Digital Terrain Modelling Using Corona and ALOS PRISM Data to Investigate the Distal Part of Imja Glacier,Khumbu Himal,Nepal

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Journal of Mountain science 2011年第3期8卷 390-402页

作者： LAMSAL Damodar SAWAGAKI Takanobu WATANABE Teiji Graduate school of Environmental science Hokkaido University Faculty of Environmental earth science Hokkaido University

This study used Corona KH-4A and Advanced Land Observing Satellite (ALOS) PRISM images to generate digital terrain models (DTMs) of the distal part of Imja Glacier,where a few supraglacial ponds (～0.07 km 2) expanded into the large Imja Glacier Lake (Imja Tsho,～0.91 km 2) between 1964 and *** and subsequently derived topographical maps with contour intervals of 1 m were created from the high-resolution images (Corona in 1964 and ALOS in 2006) in the Leica Photogrammetric Suite (LPS) *** DTMs and topographic maps provided excellent representation of the elevation and micro-topography of the glacier surface,such as its supra-glacial ponds/lake,surface depressions,and moraine ridges,with an error of about +/-4 m (maximum).The DTMs produced from the Corona and ALOS PRISM images are suitable for use in studies of the surface change of *** topographical maps produced from the Corona data (1964) showed that part of the dead ice in the down-glacier area was even higher than the top of the lateral moraine ridges,while the glacier surface in the up-glacier area was noticeably lower than the moraine *** suggests more extensive melting of glacier ice in the up-glacier area before *** average lowering of the glacier surface from 1964 to 2006 was 16.9 m for the dead-ice area west of the lake and 47.4 m for the glacier surface east of the lake;between 1964 and 2002,the lake surface lowered by 82.3 *** figures represent average lowering rates of 0.4,1.1,and 2.2 m/year for the respective areas.

关键词： Imja Glacier Nepal Himalaya DTM Topographic map Surface lowering Corona ALOS PRISM

First-principles investigation of the concentration effect on equilibrium fractionation of Ca isotopes in forsterite

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Acta Geochimica 2019年第4期38卷 497-507页

作者： Yahui Song Yonghui Li Wenzhong Wang Zhongqing Wu Laboratory of Seismology and Physics of earth’s Interior School of Earth and Space Sciences University of Science and Technology of China

Previous theoretical studies have found that the concentration variations within a certain range have a prominent effect on inter-mineral equilibrium isotope fractionation(10^3 lna).Based on the density functional theory,we investigated how the average Ca–O bond length and the reduced partition function ratios(10^3 lnb)and103lna of 44 Ca/40 Ca in forsterite(Fo)are affected by its Ca *** results show that Ca–O bond length in forsterite ranges from 2.327 to 2.267 A with the Ca/(Ca+Mg)varying between a narrow range limited by an upper limit of 1/8 and a lower limit of 1/***,outside this narrow range,i.e.,Ca/(Ca+Mg)is lower than1/64 or higher than 1/8,Ca–O bond length becomes insensitive to Ca concentration and maintains to be a *** the 10^3 lnb is negatively correlated with Ca–O bond length,the 10^3lnb significantly increases with decreasing Ca/(Ca+Mg)when 1/64

关键词： Ca isotope First-principles calculations Forsterite Concentration effect Equilibrium isotope fractionation

Halogen composition and heterogeneity in the continental lithospheric mantle

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science China earth sciences 2025年第1期 310-314页

作者： Chunfei CHEN State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences China University of Geosciences

1. Introduction Halogens, including fluorine(F), chlorine(Cl), bromine(Br), and iodine(I), are highly mobile and water-soluble elements that can become significantly enriched in melts and fluids. In fluids and melts, halogens react with nearly all metals and readily form complexes with metal cations, significantly influencing the distribution of metal elements between different phases. Therefore, halogens play a crucial role in the migration, enrichment, and mineralization of key metals in the lithosphere(Weis et al., 2012; Liu et al., 2024).

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Water solubility in orthopyroxene: Dependence on temperature and Al content

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Chinese science Bulletin 2013年第32期58卷 3895-3902页

作者： ZHANG BaoHua MATSUZAKI Takuya WU XiaoPing Institute for Study of the earth's Interior Okayama University school of earth and Space science University of Science and Technology of China

The water solubility in Al-Fe-Mg orthopyroxene[(Mg,Fe,Al)(Si,Al)O3:XFe=0.1]was investigated as a function of temperature and Al *** were performed at 10 kbar with temperatures ranging from 800 to 1200°C under water-saturated *** contents in the(Mg,Fe)SiO3–H2O–Al2O3system were determined using unpolarized Fourier transform infrared *** present results show that water solubility in Al-bearing orthopyroxene decreases systematically with temperature from approximately 1 weight%at 800°C to 568±58 ppm at 1200°C and increase significantly with increasing Al2O3contents under the same annealing temperature and *** with published results on the dependence of hydroxyl solubility on water fugacity and pressure,the present results can be described by the relation20.5OH H O()exp nC A T f1bar solid,R H V P T where A=0.0024±0.0015 ppm/bar0.5,1bar H=103.348±9.768 kJ/mol,andsolid V=9.2±1.1cm3/*** equation implies that the incorporation mechanism of water in aluminous orthopyroxene involves the isolated OH *** on the experimentally established solubility model used in this study,it is suggested that water solubility decreases with increasing temperature under typical upper mantle *** predicted temperature dependence of water solubility is in good agreement with the previous experimental observations in Al-bearing orthopyroxene,but the opposite dependence is observed in Al-free ***,our estimation of the water solubility in upper-mantle minerals as a function of depth for a typical oceanic geotherm might be of potential importance in interpreting the geophysical observations.

关键词：溶解度模型温度范围水饱和斜方辉石傅里叶变换红外光谱法温度依赖性 AI 实验观测

New Data of Macrofossils in the Ediacaran Wenghui Biota from Guizhou,South China

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Acta Geologica Sinica(English Edition) 2016年第5期90卷 1611-1628页

作者： WANG Ye WANG Yue DU Wei WANG Xunlian school of earth sciences and Resources China University of Geosciences school of Resources and Environments Guizhou University Department of earth science and Astronomy The University of Tokyo

The abundance and diversity of macrofossils in the Ediacaran have attracted much *** upper Doushantuo macrobiotas in South China,including the Miaohe biota from Hubei and the Wenghui biota from Guizhou,are mainly preserved as the carbonaceous compressions and dominated by macroscopic algae and ***,we describe 10 genera and 10 species（including 6 new genera and species） of macrofossils from the Wenghui *** present,the Wenghui biota yields macrofossils in more than 31 genera and 33 species,excluding those given no image and established on a few unascertained *** on the occurrence and distribution of macrofossils in both Miaohe and Wenghui areas,the middle-late Ediacaran（back shales of the upper Doushantuo Formation） in South China can be subdivided into two assemblage biozones in biostratigraphy：（i） the Protoconites-Linbotulitaenia-Eoandromeda Anomalophton assemblage biozone characterized by abundant and diverse macrofossils and by the ranges of Protoconites,Linbotulitaenia and Anomalophton;and（ii） the Baculiphyca-Gesinella-Cucullus-Beltanelliformis assemblage biozone characterized by the acme of the longer macrofossils Baculiphyca and Gesinella,and by few shorter and discoidal macrofossils.

关键词： macrofossils Wenghui biota Doushantuo Formation Ediacaran South China

Chronological Study of Coal-seam Water and its Implication on Gas Production in the South Qinshui Basin

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 207-219页

作者： CHEN Biying FANG Lujia LANG Yunchao XU Sheng LIU Congqiang ZHANG Luyuan HOU Xiaolin Institute of Surface-earth System science School of Earth System ScienceTianjin UniversityTianjin 300072China Institute of earth Environments Chinese Academy of SciencesXi’an 710061China

The knowledge of the residence time of formation water is fundamental to understanding the subsurface flow and hydrological *** better identify the origin and evolution of coal seam water and its impact on gas storage and production,this study collected coalbed methane co-produced water in the southeast Qinshui Basin and detected chemical and isotopic compositions,especially 36Cl and 129I *** calculated tracer ages of 129I(5.2–50.6 Ma)and 36Cl(0.13–0.76 Ma)are significantly younger than the age of coal-bearing formation(Pennsylvanian-Cisuralian),indicating freshwater recharge after coal *** model that utilises 129I/I and 36Cl/Cl ratios to constrain the timing of recharge and the proportion of recharge water reveals that over 60%of pre-anthropogenic meteoric water entered coal seams since 10 Ma and mixed with residue initial deposition water,corresponding to the basin inversion in *** spatial distribution of major ion concentrations reveals the primary recharge pathway for meteoric water from coal outcrops at the eastern margin to the basin *** study demonstrates the occurrence of higher gas production rates from wells that accept water recharge in recent times and suggests the possible potential of the non-stagnant zones for high gas production.

关键词： CBM co-produced water iodine-129 chlorine-36 water chemistry Qinshui Basin

Mesozoic mafic magmatism in North China:Implications for thinning and destruction of cratonic lithosphere

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science China earth sciences 2018年第4期61卷 353-385页

作者： Yongfei ZHENG Zheng XU Zifu ZHAO Liqun DAI CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space ScienceUniversity of Science and Technology of China

The North China Craton(NCC) has been thinned from >200 km to <100 km in its eastern part. The ancient subcontinental lithospheric mantle(SCLM) has been replaced by the juvenile SCLM in the Meoszoic. During this period, the NCC was destructed as indicated by extensive magmatism in the Early Cretaceous. While there is a consensus on the thinning and destruction of cratonic lithosphere in North China, it has been hotly debated about the mechanism of cartonic *** study attempts to provide a resolution to current debates in the view of Mesozoic mafic magmatism in North China. We made a compilation of geochemical data available for Mesozoic mafic igneous rocks in the NCC. The results indicate that these mafic igneous rocks can be categorized into two series,manifesting a dramatic change in the nature of mantle sources at ~121 Ma. Mafic igneous rocks emplaced at this age start to show both oceanic island basalts(OIB)-like trace element distribution patterns and depleted to weakly enriched Sr-Nd isotope compositions. In contrast,mafic igneous rocks emplaced before and after this age exhibit both island arc basalts(IAB)-like trace element distribution patterrs and enriched Sr-Nd isotope *** difference indicates a geochemical mutation in the SCLM of North China at^121 Ma. Although mafic magmatism also took place in the Late Triassic, it was related to exhumation of the deeply subducted South China continental crust because the subduction of Paleo-Pacific slab was not operated at that time. Paleo-Pacific slab started to subduct beneath the eastern margin of Eruasian continent since the Jurrasic. The subducting slab and its overlying SCLM wedge were coupled in the Jurassic, and slab dehydration resulted in hydration and weakening of the cratonic mantle. The mantle sources of ancient IAB-like mafic igneous rocks are a kind of ultramafic metasomatites that were generated by reaction of the cratonic mantle wedge peridotite notonly with aqueous solutions

关键词： Cratonic destruction Mafic magmas IAB-like series OIB-like series Lithospheric thinning Slab subduction