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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

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

Precise dating of abrupt shifts in the Asian Monsoon during the last deglaciation based on stalagmite data from Yamen Cave, Guizhou Province, China

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Science China Earth Sciences 2010年第5期53卷 633-641页

作者： EDWARDS R. Lawrence Department of geology and geophysics University of Minnesota

Based on 33 U/Th dates and 1020 oxygen isotopic data from stalagmite Y1 from Yamen Cave, Guizhou Province, China, a record of the Asian Summer Monsoon (ASM) was established. The record covers the last deglaciation and the early Holocene (from 16.2 to 7.3 ka BP) with an average oxygen isotope resolution of 9 years. The main millennial-scale deglacial events first identified in Greenland (Greenland Interstadial Events: GIS 1e through GIS 1a) and later in China are clearly present in the Y1 record. By analogy to earlier work, we refer to these as Chinese Interstadials (CIS): CIS A.1e to CIS A.1a. The onset of these events in Y1 δ18O records are nominally dated at: 14750±50, 14100±60, 13870±80, 13370±80, and 12990±80 a BP. The end of CIS A.1a or the beginning of the Younger Dryas (YD) event is nominally at 12850±50 a BP and the end of the YD dates to 11500±40 a BP. The δ18O values shift by close to 3‰ during the transition into the Bφlling-Allerφd (BA, the onset of CIS A.1e) and at the end of the YD. Comparisons of Y1 to previously published early Holocene records show no significant phase differences. Thus, the East Asia Monsoon and the Indian Monsoon do not appear to have been out of phase during this interval. The Y1 record confirms earlier work that suggested that solar insolation and North Atlantic climate both affect the Asian Monsoon.

关键词： stalagmite Asian Monsoon the last deglaciation Holocene U-series dating Yamen Cave

Some Issues on the Strength of the Lithosphere

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Journal of Earth Science 2011年第2期22卷 131-136页

作者： Shun-ichiro Karato Department of geology and geophysics Yale University

The strength of the oceanic and continental lithosphere has important controls on some of the major geological processes on earth including the operation of plate tectonics and the long-term stability of the continental roots. However, explaining these major geological features from the experi- mental and theoretical studies on the strength of rocks is challenging and some of the existing models for the strength of the lithosphere do not explain these main geological observations. A brief review is provided to summarize recent progress in these areas with the emphasis on experimental studies.

关键词： lithosphere plate tectonics continent.

Circulation background of climate patterns in the past millennium: Uncertainty analysis and re-reconstruction of ENSO-like state

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Science China Earth Sciences 2016年第6期59卷 1225-1241页

作者： TAN Ming Key Laboratory of Cenozoic geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences

The question of whether or not global warming has paused since more than ten years ago, namely ＂warming hia- tus＂, has attracted the attention of climate science community including the IPCC. Some authors have attributed the ＂warming hiatus＂ to the internal changes in the climate system, i.e., the recombination of ocean-atmosphere circulations. Therefore, it is necessary to propose higher requirements on reconstructing circulation background of climate change for the past millennium. However, the analyses of changes in atmospheric circulation over the last millennium as well as the conclusions of related re- gional climate patterns are so widely different and contradictory, bringing uncertainties to our understanding of regional even global climate change to a great extent. On the other hand, in the last 10 years the high-precision U/Th-dated stalagmite oxygen isotope ratio （δ^18O） sequences provided an accurate chronological frame for the paleoclimate study of the middle and late Pleistocene, in which all authors from China took the Chinese stalagmite δ^18O as the summer monsoon index without excep- tion. However, this point of view misleads the climate scientists into thinking that the stalagmite δ^18O can be as the proxy of precipitation amount. Nevertheless, it is well known that all of these records have a lot in common in the low frequency trend. However, most sequences cannot be calibrated by instrumental precipitation records, and thus the uncertainty of the climate research framework of China and even of the world has increased. Therefore, it is imperative for climatology to clarify the origin of contradiction and to reduce the uncertainty as early as possible. On the basis of analyzing the significance of stalag- mite ~180 in the monsoon regions of China, the author tries to propose a new circulation proxy in this paper： integrating the Chinese stalagmite oxygen isotope sequence to reconstruct the tropical Pacific sea surface temperature gradient, i.e., th

关键词： The past millennium ENSO Circulation background Climate pattern WPSH Stalagmite δ^18O Circulation recombination

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.

Review of the bennettitalean genus Weltrichia

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Journal of Palaeogeography 2019年第2期8卷 109-129页

作者： Mihai Emilian Popa Faculty of geology and geophysics Department of Geology and Doctoral School of GeologyLaboratory of PalaeontologyUniversity of Bucharest

The bennettitalean male reproductive structure Weltrichia Braun 1849 *** 1969(Family Williamsoniaceae) is discussed from several points of view,including anatomy and morphology,species diversity and validity,phytogeographical and stratigraphical distribution,and reproduction strategy.A very rare fossil,genus Weltrichia includes 25 valid species distributed in both hemispheres during Triassic and Jurassic *** contribution critically reviews the systematics of the entire genus,together with its stratigraphical and palaeophytogeographical significance.

关键词： Bennettitales Weltrichia Male reproductive structure Triassic Jurassic

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.