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Effects of mesoscale gravity waves on sporadic E simulated by a one-dimensional dynamic model

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Earth and Planetary Physics 2025年第1期9卷 1-9页

作者： Xu Zhou ZeZhong Li XinAn Yue LiBo Liu Key Laboratory of Earth and Planetary Physics/Heilongjiang Mohe National Geophysical Observatory/Beijing National Observatory of Space Environment Institute of Geology and GeophysicsChinese Academy of Sciences(CAS)Beijing 100029China College of Earth and Planetary sciences University of Chinese Academy of SciencesBeijing 100049China CAS Center for Excellence in Comparative Planetology/CAS Key Laboratory of Geospace Environment/Mengcheng National Geophysical Observatory University of Science and Technology of ChinaHefei 230026China

In addition to being driven by tidal winds,the sporadic E(Es)layers are modulated by gravity waves(GWs),although the effects are not yet comprehensively *** this article,we discuss the effects of mesoscale GWs on the Es layers determined by using a newly developed model,MISE-1D(one-dimensional Model of Ionospheric Sporadic E),with low numerical dissipation and high *** by the wind fields resolved by the high-resolution version of the Whole Atmosphere Community Climate Model with thermosphere and ionosphere extension(WACCM-X),the MISE-1D simulation revealed that GWs significantly influence the evolution of the Es layer above 100 km but have a very limited effect at lower *** effects of GWs are diverse and complex,generally including the generation of fluctuating wavelike structures on the Es layer with frequencies similar to those of the *** mesoscale GWs can also cause increases in the density of Es layers,or they can disperse or diffuse the Es layers and increase their *** addition,the presence of GWs is a key factor in sustaining the Es layers in some cases.

关键词： sporadic E ion tidal layer gravity waves numerical simulation

Mission and challenges of higher education: an interview with G.Q. Max Lu, the president of the University of Surrey

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National Science Review 2020年第6期7卷 1108-1113页

作者： Ling Wang Zhengtang Guo the institute of geology and geophysics Chinese Academy of Sciences

The University of Surrey (referred to as Surrey hereafter) is one of the renowned universities in the UK that was established on 9 September1966 with the grant of its Royal Charter and its roots go back to Battersea Polytechnic institute, founded in 1891. Surrey is the research hub of small satellites, mobile telecommunication and artificial intelligence in Europe. In 2016, Surrey was named as ‘Univer-

关键词： Biographies

Geochemistry of ore-forming fluids and geological significance of the Kuoerzhenkuola gold field in Xinjiang, China

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Science China Earth sciences 2005年第11期48卷 1921-1931页

作者： SHEN Ping SHEN Yuanchao LIU Tiebing LI Guangming ZENG Qingdong institute of geology and geophysics Chinese Academy of Sciences Beijing 100029 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

The Kuoerzhenkuola gold field (including the Kuoerzhenkuola and the Buerkesidai gold deposits) is the most important one in the Sawuer gold belt, northern Xinjiang, China. Iso-topic studies including D, O, He, C, S, Pb and Sr reveal that the ore-forming fluids of the Kuo-erzhenkuola and the Buerkesidai deposits shared the same source: the water of ore fluids was magmatic water and minor meteoric water; the mineralizers and ore materials derived mainly from mantle beneath the island arc, and partially from crust. The ore-forming fluids of two depos-its are a mixture of mantle-derived fluids incorporated by crust-derived fluid, and meteoric water. Based on these results, combined with the consideration of the tectonic setting and geological features, we suggest that the two gold deposits in the Kuoerzhenkuola gold field, Sawur gold belt share the same genesis, and are volcanogenic hydrothermal gold deposits occurring in the same caldera.

关键词： ore-forming fluids, inclusions, isotope, volcanogenic late-stage hydrothermal gold deposits, Kuoerzhen-kuola gold field

Crust and upper mantle structure of the Ailao Shan-Red River fault zone and adjacent regions

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Science China Earth sciences 2005年第2期48卷 156-164页

作者： XU Yi LIU Jianhua LIU Futian SONG Haibin HAO Tianyao JIANG Weiwei institute of geology and geophysics Chinese Academy of SciencesBeijing100029China Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China

Using arrival data of the body waves recorded by seismic stations, we reconstructed the velocity structure of the crust and upper mantle beneath the southeastern edge of the Tibetan Plateau and the northwestern continental margin of the South China Sea through a travel time tomography technique. The result revealed the apparent tectonic variation along the Ailao Shan-Red River fault zone and its adjacent regions. High velocities are observed in the upper and middle crust beneath the Ailao Shan-Red River fault zone and they reflect the character of the fast uplifting and cooling of the metamorphic belt after the ductile shearing of the fault zone, while low velocities in the lower crust and near the Moho imply a relatively active crust-mantle boundary beneath the fault zone. On the west of the fault zone, the large-scale low velocities in the uppermost mantle beneath western Yunnan prove the influence of the mantle heat flow on volcano, hot spring and magma activities, however, the upper mantle on the east of the fault zone shows a relatively stable structure similar to the Yangtze block. The low velocities of the deep mantle beneath the southeastern extending segment of the fault zone are probably related to the mantle convection produced by the pull-apart of the South China Sea.

关键词： Ailao Shan-Red River fault zone, seismic tomography, crust and upper mantle, velocity structure.

Gold mineralization age of the Anjiayingzi gold deposit in Chifeng County, Inner Mongolia and implications for Mesozoic metallogenic explosion in North China

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Science China Earth sciences 2004年第2期47卷 115-121页

作者： LI Yonggang ZHAI Mingguo YANG Jinhui MIAO Laicheng GUAN Hong institute of geology and geophysics Chinese Academy of Sciences Beijing 100029 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

The Anjiayingzi gold deposit in Chifeng County, Inner Mongolia is located in the central part of the gold mineralization belt of the northern margin of the North China Craton (NCC), and is adjacent to the Paleozoic Inner Mongolia-Da Hinggan Mountains orogenic belt in the north. The Chifeng-Kaiyuan fault, which separates the NCC from this orogenic belt, is considered to be a regional ore-controlling structure. The Anjiayingzi gold deposit is a mediate-size quartz lode-gold deposit and is hosted by the Anjiayingzi quartz monzonite that was emplaced into the basement composed of early Precambrian gneisses. Rhyolitic and porphyritic dikes are generally associated with the gold mineralization. Zircon U-Pb analyses suggest that the Anjia- yingzi granite was emplaced from 132 Ma to 138 Ma, while the rhyolitic dikes that occupy the same fracture system as the gold-bearing quartz veins and locally crosscut the gold lodes crystallized from 125 Ma to 127 Ma. These results constrain the mineralization age between 126 Ma and 132 Ma, early Cretaceous time for the Anjiayingzi gold deposit. This mineralization age is consistent with that of the gold deposits in other major gold-bearing areas of the NCC, such as the Jiaodong Peninsula and the Xiaoqinling Mountain, and specially is roughly coeval with the geodynamic reversion of the NCC in Mesozoic. This coincidence probably indicates that the gold deposits in the NCC, including the Anjiayingzi deposit, formed in a similar geodynamic setting characterized by large-scale thinning of the lithosphere underlying the NCC.

关键词： Anjiayingzi, gold deposit, granite, zircon, geochronology, explosive metallogeny.

An investigation on the wind profiles and gravity wave dynamics in MLT region based on the meteor radars from the Meridian Project

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Earth and Planetary Physics 2025年第1期9卷 29-38页

作者： Tai Liu Zhe Wang MengXi Shi Willie Soon ShiCan Qiu Department of geophysics College of the Geology Engineering and GeomaticsChang’an UniversityXi’an 710054China Center for Environmental Research and Earth sciences(CERES) SalemMA 01970USA institute of Earth Physics and Space Science(ELKH EPSS) 9400SopronHungary

The meteor radar can detect the zenith angle,azimuth,radial velocity,and altitude of meteor trails so that one can invert the wind profiles in the mesosphere and low thermosphere(MLT)region,based on the Interferometric and Doppler *** this paper,the horizontal wind field,gravity wave(GW)disturbance variance,and GW fluxes are analyzed through the meteor radar observation from 2012−2022,at Mohe(53.5°N,122.4°E)and Zuoling(30.5°N,114.6°E)stations of the(chinese)Meridian *** Lomb−Scargle periodogram method has been utilized to analyze the periodic variations for time series with observational data *** results show that the zonal winds at both stations are eastward dominated,while the meridional winds are southward *** variance of GW disturbances in the zonal and meridional directions increases gradually with height,and there is a strong pattern of annual *** zonal momentum flux of GW changes little with height,showing weak annual *** meridional GW flux varies gradually from northward to southward with height,and the annual periodicity is *** both stations,the maximum values of zonal and meridional wind occur close to the peak heights of GW flux,with opposite *** observational evidence is consistent with the filtering *** horizontal wind velocity,GW flux,and disturbance variance of the GW at Mohe are overall smaller than those at Zuoling,indicating weaker activities in the MLT at *** power spectral density(PSD)calculated by the Lomb−Scargle periodogram shows that there are 12-month period and 6-month period in horizontal wind field,GW disturbance variance and GW flux at both stations,and especially there is also a 4-month cycle in the disturbance *** PSD of the 12-month and 6-month cycles exhibits maximum values below 88 km and above 94 km.

关键词： meteor radar wind field gravity wave Lomb−Scargle method

Fenitized Wall Rock Geochemistry of the First Carbonatite Dyke at Bayan Obo, Inner Mongolia, China

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Acta Geologica Sinica(English Edition) 2018年第2期92卷 600-613页

作者： WANG Kaiyi ZHANG Jien YU Liangjun FANG Aimin DONG Ce HU Fuyou institute of geology and geophysics Chinese Academy of Sciences

The first carbonatite dyke at Bayan Obo is well exposed on the surface for a length and width of approximately 60 m and 1.1-1.5 m, respectively. Along its strike, the fenitized H1 （Qs） and H2 （Cs） quartzite is replaced by Na-amphiboles, aegirines, and alkali-feldspars, intermittently stretching as far away as 800 m in length. Based on petrographical characteristics, the dyke＇s fenitized wall rocks are divisible into different zones：（1） outer, （2） middle, and （3） inner. The outer zone is 5-17 m from the NW margin of the dyke. The middle zone is located at 3.5-5 m from the NW margin of the dyke. The inner contact zone is located between direct contact with the dyke and 3.5 m from the dyke. In the outer zone, upon visual examination, no evidence of outcrop fenitization was found and the major elemental rock composition is nearly identical to the unaltered H1 and H2 lithologies. In the thin sections, however, small amounts of Na-amphibole and phlogopite are present. Despite relatively poor development throughout the 5 m of fenitization, the wall rocks have retained at least a small geochemical signature comparable to the original sedimentary protolith. The fenites occurring in the inner zone exhibit distinct variations, not only for the sharp contact at the outcrop scale, but also for variations in major, rare earth elements （REE）, and trace elements and Sm-Nd isotope composition. The wall rocks within 3.5 m have undergone strong fenitization, inheriting the geochemical signature derived from the carbonatite dyke. Fenitization in the middle zone was not as strong, at least compared to the inner zone, but was stronger than the outer zone. Compared to some trace elements and REEs, the major elements are relatively immobile during fenitization. The Sm-Nd isotope data for the carbonatite dyke and the adjacent fenitized wall rocks, where the Sm and Nd originate solely from the dyke, plots as a six-point isochron with an age of 1308~56 Ma. This age is identical to that of or

关键词： Bayan Obo first carbonatite dyke fenitization

Properties of soils in Grove Mountains,East Antarctica

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Science China Earth sciences 2003年第7期46卷 683-693页

作者：李潇丽刘小汉琚宜太黄费新 institute of geology and geophysics Chinese Academy of Sciences

Three cold desert soil sites were first found in the southern Mount Harding, Grove Mountains, East Antarctica. The soils are characteristics of the widespread occurrence of surface desert pavement, abundant water-soluble salts, strongly stained upper portion of soil profile, slightly acid and negligible organic matter content. A 1:5 soil-water extracts analysis indicates that the dominant cations are Mg2+ and Na+, followed by Ca2+ and K+, and the main anion is SO 4 2? , then Cl? and NO 3 2? . The accumulation of water-soluble salts indicates ion transportation in the frigid and arid Antarctica environment. The distribution of the salts is related to the maximum content of moisture and clay mineral. Clay fraction migration occurs in the soils, which is different from that of other cold desert soils. The upper horizons of some profiles are generally stained, namely rubification, primarily because of the weathering of iron-bearing minerals. The reddish hues of cold desert soils have been attributed to relatively high concentrations of dithionite-extractable Fe (Fed). The weathering features of soils suggest that the soil age of this area is 0.5–3.5 Ma. No remnants of glaciations were found on the soil sites of Mount Harding, which suggests that the Antarctic glaciations have not reached the soil sites since at least 0.5 Ma, even during the Last Glacial Maximum.

关键词： the Grove Mountains, cold desert soil, desert pavement, soluble salt, Fed.

Paleomagnetic study on the Early Triassic red beds from Jiaocheng, Shanxi Province ——Local rotation and tectonic significance

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Science China Earth sciences 2004年第2期47卷 108-114页

作者： SHI Ruiping HUANG Baochun ZHU Rixiang REN Shoumai institute of geology and geophysics Chinese Academy of Sciences Beijing 100029China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029China

Paleomagnetic and rock magnetic study has been conducted on the Early Triassicred beds of Liujiagou Formation from Jiaocheng, Shanxi Province. Hematite was shown as themain magnetic mineral. After eradicating an initial viscous component at room temperature to～100℃-200℃, thermal demagnetization shows that most samples contain two remanencecomponents, intermediate-temperature remanence component at 250℃-500℃ and high-tem-perature component at 500℃-680℃. The intermediate-temperature component has a negativefold test at the 95% confidence level. And the pole position of the intermediate-temperaturecomponent in geographic coordinates is correlated with the Middle Jurassic reference pole of theNorth China Block (NCB) within the 95% confidence, suggesting that it might be a remagnetiza-tion component acquired during the Yanshanian period. The high-temperature component con-tains both reversal and normal polarities with positive fold test and C-level positive reversal test atthe 95% confidence level, which suggests that this high-temperature component can be regardedas primary magnetization. Comparison of this newly obtained Early Triassic paleopole with thecoeval mean pole of the Ordos Basin suggests that a locally relative rotation may have happenedbetween the Ordos and the Jiaocheng area of Shanxi Province. This rotation may be related withtwo faults: one is Lishi big fault separating Ordos from Shanxi and the other is Jiaocheng big fault,which is situated in the southeast of sampling locality and was still in motion during the Cenozoic.

关键词： Jiaocheng, Shanxi, paleomagnetism, Early Triassic, local rotation.