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Hydroxyl groups in nonmetamict chevkinite-(Ce):a crystal chemical discussion

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Hydroxyl groups in nonmetamict chevkinite-(Ce):a crystal che...

中国科学院地质与地球物理研究所2008学术年会

作者：杨主明 Franz Pertlik Michel Fleck Key laboratory of Engineering Geomechanics Institute of Geology and GeophysicsChinese Academy of Sciences Institute of Mineralogy and Crystallography University of ViennaGeozentreAlthanstrasse 14A-1090 ViennaAustria

The minerals of chevkinite group were commonly considered to be anhydrous *** infrared absorption spectrum of natural nonmetamict chevkinite-(Ce) from the aegirine-alkali granite,Mianning,Sichuan Province,China,exhibited two broad peaks in the 3600-2800 cm region owing to the OH *** corresponding HO content required for the charge balance in formula was 1.27%. The O-H···O bond lengths maight cover from 0.2658 to 0.2794 nm by the correlated OH stretching *** electrostatic charge balance for chevkinite-(Ce) based on the assigned site-population from chemical data was calculated without the hydrogen *** resulting empirical bond-valence sum on 06,08,02,03,05,and 04 ranged from 1.73 to 1.95 *** partial substitution of O by OH may occur in four atom sites:06,02,04,and *** small differences in the bond-valence sums between the supposed donors and acceptors may mean a mixed donor/acceptor role of the involved oxygen *** IR spectral features between 3394 and 3035 cm consisted of various hydrous species at different structural sites and *** OH groups in the chevkinite-(Ce) appeared to be involved in local charge imbalance in the structure and to be present when the mineral crystallized hydrothermally.

关键词： chevkinite-(Ce) infrared spectrum bond-valance sum bond length hydroxyl groups rare earths

A clipping algorithm for real-scene 3D models

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International Journal of Digital Earth 2023年第1期16卷 464-485页

作者： Jianhua Chen Xu Liu Bingqian Wang Jian Lu College of geophysics Chengdu University of TechnologyChengduPeople’s Republic of China Chengdu Rescue and Disaster Reduction Technology Center ChengduPeople’s Republic of China Sichuan Huadi Construction Engineering Co. Ltd.ChengduPeople’s Republic of China

The development of unmanned aerial vehicle(UAV)oblique photogrammetric technology provides a good foundation for the rapid construction of large-scale and high-definition real-scene 3D ***,due to the limitations of the modeling process,irrelevant feature data cannot be eliminated in the modeling *** built models contain irrelevant features and model distortions caused by *** present,most existing clipping algorithms cannot effectively clip real-scene 3D models that are organized as a whole or with levels of detail(LODs).Therefore,this paper proposes a novel algorithm for clipping real-scene 3D models from any perspective based on clipping boundary lines thatfit the surfaces of the *** results of the clipping experiments for 3D models constructed with oblique UAV images show that this algorithm can effectively clip any part of the 3D models,that the clipping results of each level model closelyfit the corresponding clipping boundary lines,and that the accuracy of the clipping results is very ***,the time complexity of the algorithm is O(n^(2)).In conclusion,the algorithm proposed in this paper provides correct and effective clipping results for real-scene 3D models with LODs that are constructed with photogrammetric or 3D laser scanning data.

关键词： Real-scene 3D models Clip Linesfitting 3D model surfaces Triangular mesh

Lineament Analysis of Morphostructures of the Uchur-Maya Basin (Southeastern Siberian Platform) from SRTM Data: Relationship with Metallogeny

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International Journal of Geosciences 2012年第6期3卷 1176-1186页

作者： Gul’shat Z. Gil’manova Mikhail V. Goroshko Oleg V. Rybas Alexei N. Didenko Institute of Tectonics and geophysics Far East Branch Russian Academy of Sciences Khabarovsk Russia

Based on digital elevation models SRTM03 and SRTM30_Plus (Shuttle Radar Topography Mission Survey) the technique for detecting major structural elements and elucidating details of the geologic structure including discrimination of linear structures and texture features is elaborated. The computation of the modulus of the first derivative by the co- ordinate, i.

关键词： Space SRTM Survey Lineaments The Uchur-Maya Basin Metallogeny

Three-dimensional velocity structure around the focal area of the 2021 MS6.4 Yangbi earthquake

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Earthquake Science 2021年第5期34卷 399-412页

作者： Yunpeng Zhang Weitao Wang Wei Yang Min Liu Jinbo Su Xiaobin Li Jun Yang Institute of geophysics China Earthquake AdministrationBeijing 100081China Key laboratory of Earthquake Source Physics China Earthquake AdministrationBeijing 100081China China University of Geosciences(Beijing) Beijing 100083China Urumqi Institute of Central Asian Seismology China Earthquake AdministrationUrumqi 830011China Dali Center China Seismic Experimental SiteDali 671000China

On May 21,2021,an MS6.4 earthquake occurred in Yangbi,Yunnan province,China,which exhibited typical foreshock-mainshock-aftershock *** better understand the velocity structure of the focal area and adjacent fault zones,Pg/Sg travel times at 12 seismic stations for the local earthquakes with ML≥1.5 from 2009-2019 and the Yangbi sequence in May of 2021 were used to invert the three-dimensional(3D)structures for both vP and v_(P)/v_(S).The obtained structure extends deeply to 15 km for area(25°N-26.5°N,99.5°E-101°E)at a horizontal resolution of 10×10 km,and the accuracy of the v_(P) velocity was verified using airgun signals excited by the Binchuan Airgun Transmitting Seismic Station(BATSS).The resulting v_(P) and v^(P)/v_(S) images correlate with existing fault zones and the Yangbi sequence,including:(1)The shallow velocity structure at 0 km agrees with local topography,where the Binchuan basin exhibits low-v_(P) and high-v_(P)/v_(S) *** 3-15 km,v_(P) and v_(P)/v_(S) show variations,and the boundaries are consistent with the main faults(e.g.,the Weixi-Qiaohou-Weishan,Honghe,and Chenghai faults).(2)The largest foreshock(M_(S)5.6),main-shock(MS6.4),and largest aftershock(M_(S)5.2)occurred near the boundaries where both vP and v_(P)/v_(S) have clear contrasts.(3)Small earthquakes are also concentrated in the transition zone between high-and low-vP and v_(P)/v_(S) anomalies,and are biased toward low-v_(P)/v_(S) zones.(4)Boundaries in v_(P) and v_(P)/v_(S) are observed at 20 km west of the Weixi-Qiaohou-Weishan fault,indicating that there may exist one hidden fault.

关键词： MS6.4 Yangbi earthquake Honghe fault Weixi-Qiaohou-Weishan fault body wave tomography air-gun source.

Comparison of two great Chile tsunamis in 1960 and 2010 using numerical simulation

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Earthquake Science 2011年第5期24卷 475-483页

作者： Ruizhi Wen Yefei Ren Xiaojun Li Rong Pan Institute of Engineering Mechanics China Earthquake Administration Harbin 150080 China Institute of geophysics China Earthquake Administration Beijing 100081 China Nuclear and Radiation Safety Center Ministry of Environmental Protection Beijing 100082 China

Great differences in hazard and losses were shown from two tsunamis, both generated in Chile, one in 1960 and the other in 2010. Numerical simulation was applied to the tsunami analysis. The fault dislocation of the seafioor was assumed to equal to the initial tsunami wave field, which can be calculated by the formula of fault dislocation in the elastic isotropic half-space. The linear long wave theory was used as the tsunami hydrodynamic model, and the finite difference method and leap-frog scheme were selected for solving the equations. The accuracy of the simulated results was verified by the observed data in five tide gauges. By means of two scenario tsunamis, the analytical results show that the earthquake magnitude, bathymetry in rupture zone and rapid release of warning information in 2010 tsunami are the main explanations of the aforementioned great difference.

关键词： Chile earthquake tsunami numerical simulation

Petrographic Shock Indicators,Cosmic Ray Exposure Ages and Gas Retention Ages of a H and an L Chondrite from Antarctica

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Petrographic Shock Indicators,Cosmic Ray Exposure Ages and G...

中国矿物岩石地球化学学会第九次全国会员代表大会暨第16届学术年会

作者： P.M.Ranjith 贺怀宇 MIAO Bing-kui LIN Yang-ting Key laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of Sciences University of Chinese Academy of Sciences College of Earth Sciences Guilin University of technology

Petrographic shock indicators and noble gas signatures in the ordinary chondrites Grove Mountain(GRV)13083(H4)and GRV 13095(L5)were studied in order to investigate the degrees of shock metamorphism and impact related chronologies on H and L chondrite parent *** on the impact teatures in silicates and metal-troilite assemblages,the shock stages of the samples were classified as S6 and

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Crustal structure across the Kunlun fault from passive source seismic pro filing in East Tibet

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Crustal structure across the Kunlun fault from passive sourc...

中国科学院地质与地球物理研究所2014年度（第14届）学术年会

作者： Tao Xu Zhenbo Wu Zhongjie Zhang Xiaobo Tian Yangfan Deng Chenglong Wu Jiwen Teng State Key laboratory of Lithosphere Evolution Institute of Geology and GeophysicsChinese Academy of Sciences University of Chinese Academy of Sciences Guangzhou Institute of Geochemistry Chinese Academy of Sciences

The crust beneath the northeastern(NE) Tibetan Plateau records the imprints on Paleozoic Kunlun orogen and far field effects from continental collision and convergence between the Indian and Eurasian plates. A passive source seismic pro file was conducted across eastern Kunlun mountains(also called Animaqing suture belt). Receiver function imaging and H-k stacking results with this dataset demonstrate that(1) crust slightly thins from about 64 km under the Songpan–Ganzi terrane to about 56–62 km under the Qaidam–Kunlun block and the Qilian block;(2) Moho topography is relatively smooth with gradual undulation beneath east Kunlun orogeny belt, in contrast to 2–5 km Moho step at the AKMS/Kunlun fault from previous deep seismic soundings or even no Moho topography variation from recent deep seismic re flection pro filing;(3) the average crustal Vp/Vs ratios display an increasing trend to the Kunlun fault belt from 1.76 to 1.85 in Songpan–Ganzi terrane, while decreases from 1.83 to 1.65 away from the fault belt in Qaidam–Kunlun block;(4) The high Vp/Vs ratio in Songpan–Ganzi terrane, is similar to previous results from the pro file across Longmenshan fault belt. The normal to low Vp/Vs ratio distribution in Qaidam–Kunlun block supports the viewpoint that the deformation occurring in NE Tibet is predominated by upper-crustal thickening;and(5) the thickness of non-seismogenic layer varies slightly about 40 km between 90° and 100°E, then decreases to less than 20 km around 106°E along the Kunlun fault. The change of the non-seismogenic layer thickness is consistent with the change of the lower crust thickness derived from deep seismic sounding. The increased crustal thickness may be due to the differences in the thickness of the crust of the two plates before their collision, and/or largely achieved by thickening of the lower crust, perhaps indicating a crust flow mechanism operating more strongly in the western region.

关键词： Crustal structure Kunlun fault Passive source Receiver function Common conversion point(CCP) stack Vp/Vs velocity ratio

Practical Experiences with the First Relative Gravimeter of Type Scintrex CG-6 Autograv in Dubai, The United Arab of Emirates

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World Journal of Engineering and Technology 2020年第2期8卷 237-247页

作者： Ossama S. Aly Basem Elsaka Eman A. Al Khatibi National research Institute of Astronomy and geophysics (NRIAG) Cairo Egypt Institute of Geodesy and Geoinformation University of Bonn Bonn Germany Geodesy and Hydrographic Survey Section Dubai Municipality Dubai The United Arab of Emirates

In September 2019, the Dubai Municipality of Dubai Emirate, the United Arab of Emirates, has received its first Scintrex CG-6 Autograv gravity meter. This paper describes the installation and initial gravity signals with the new CG-6 Autograv gravimeter. Two gravity field sites have been selected in Dubai City and Hatta mountainous area. The relative gravity field measurements have been recorded for about one month time span;two weeks in Dubai and two weeks in Hatta. Among different effects reducing the gravity measurements, the tide and drift corrections have been focused on this paper. Two tidal models have been applied to reduce the tide effect based on the automated ETGTAB of the CG-6 gravimeter and ETERNA3.3 software. The results regarding the tide correction show very small discrepancies between both models (ETGTAB and ETERNA3.3) of about 2.2 μGal and 2.6 μGal in terms of standard deviations at Dubai and Hatta gravity stations, respectively. So, the outcome of the precise tidal model of CG-6 Autograv gravimeter is reliable for tidal reduction within Dubai area and its surroundings. Regarding the drift correction, the CG-6 Autograv provides low instrument drift values about 2.44 μGal and -2.35 μGal per day for the Dubai and Hatta stations, respectively. Furthermore, it is recommended that the Hatta gravity station would be considered as a stable and trusted gravity site. For Dubai gravity station, the gravity observations are affected by some noises from traffic activities while recording the gravity signal during the working days. Therefore, it is recommended for Dubai gravity station to be measured during the weekends and at nights in order to avoid any noises affecting the CG-6 gravimeter.

关键词： Terrestrial Gravity Field Scintrex CG6 Autograv Drift Correction

Earthquake loss estimation by using Gross Domestic Product and population data

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Acta Seismologica Sinica(English Edition) 1997年第6期10卷 95-104页

作者：陈棋福陈禺页陈凌 1. Center for Analysis and Prediction State Seismological Bureau 100036 Beijing China2. Institute of Geophysics State Seismological Bureau 100081 Beijing China

In the traditional method of earthquake loss estimation, all the social wealthes are classified according to their structural type and occupational use. Inventory data is collected and the total loss is estimated from each facility class separately. For many regions of the world, however, the vast amount of data required by this method is difficult or impossible to obtain. The traditional method is also unable to estimate quickly the loss from an unexpected disaster earthquake. It is difficult to give the necessary risk information to help the government to rescue and relief the earthquake disaster. This paper proposes a simple estimation method of earthquake loss based on macroscopic economical index of Gross Domestic Product (GDP) and population distribution data. A preliminary nonlinear relation among hazard loss, seismic intensity and social wealth was developed by means of some earthquake disaster records during 1980～1995. This method was applied to analyze several assumed earthquakes. The preliminary analysis results show that the new method is effective and reasonable for quick assessment of earthquake loss.

关键词： earthquake disaster loss estimation assumed earthquake Gross Domestic Product population