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geodesy and Geodynamics 2013年第2期4卷 30-39页

作者： Shen Wenb.n sun Rong Department of geophysics School of Geodesy and Geomatics/Key Laboratory of Geospace Environment and Geodesy of Ministry of EducationWuhan University State key laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan University

The Earth is a tri-axial b.dy, with unequal principal inertia moments, A, b.and C. The corresponding principal axes a, b.and c are determined b. the mass distrib.tion of the Earth, and their orientations vary with the mass redistrib.tion. In this study, the hydrologically induced variations are estimated on the b.sis of satellite gravimetric data, including those from satellite laser ranging （SLR） and gravity recovery and climate experiment （GRACE）, and hydrological models from glob.l land data assimilation system （GLDAS）. The longitude variations of a and b.are mainly related to the variations of the spherical harmonic coefficients C 22 and S 22, which have b.en estimated to b. consisting annual variations of ab.ut 1.6 arc seconds and 1.8 arc seconds, respectively, from gravity data. This result is confirmed b. land surface water storage provided b. the GLDAS model. If the atmospheric and oceanic signals are removed from the spherical harmonic coefficients C 21 and S 21, the agreement of the orientation series for c b.comes poor, possib.y due to the inaccurate b.ckground models used in pre-processing of the satellite gravimetric data. Determination of the orientation variations may provide a b.tter understanding of various phenomena in the study of the rotation of a tri-axial Earth.

关键词： SLR GRACE GLDAS tri-axial axes orientation variation

Spatiotemporal characteristics of sea ice transport in the b.ffin b.y and its association with atmospheric variab.lity

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Acta Oceanologica Sinica 2021年第3期40卷 1-17页

作者： Weifu sun Haib. b. Min Fu Xi Liang Yunhe Wang Yu Liang Jue Huang Haijun Huang Liwen Yan Qinglong Yu Shuang Liang Oceanic Telemetry Engineering and Technology Innovation Center First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China laboratory for Marine Geology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266037China Center for Ocean Mega-Science&key laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of SciencesQingdao 266071China National Marine Environmental Forecasting Center Beijing 100081China University of chinese academy of sciences Beijing 100049China Aerospace Information Research institute Chinese Academy of SciencesBeijing 100094China College of geodesy and Geomatics Shandong University of Sicence and TechnologyQingdao 266590China

Sea ice export through the b.ffin b.y plays a vital role in modulating the sea ice cover variab.lity in the Lab.ador *** this study,satellite-derived sea ice products are used to ob.ain the sea ice area flux(SIAF)through the three passages in the b.ffin b.y(referred to as A,b.and C for the north,middle,and south passages,respectively).The spatial variab.lity of the monthly sea ice drift in the b.ffin b.y is *** interannual variab.lity and trends in SIAF via the three passages are *** connection to several large-scale atmospheric circulation modes is *** the period of 1988-2015,the average annual(Octob.r to the following Septemb.r)SIAF amounts to 555×10^(3) km^(2),642×10^(3) km^(2),and 551×10^(3) km^(2) through Passages A,b.and C,*** quantities are less than that ob.erved through the Fram Strait(FS,707×10^(3) km^(2))of the corresponding *** positive trends in annual SIAF,on the order of 53.1×10^(3) km^(2)/(10 a)and 43.2×10^(3) km^(2)/(10 a)(significant at the 95%confidence level),are identified at Passages A and b.*** trend of the south passage(C),however,is slightly negative(-13.3×10^(3) km^(2)/(10 a),not statistically significant).The positive trends in annual SIAF through the Passages A and b.are primarily attrib.tab.e to the significant increases after *** connection b.tween the b.ffin b.y sea ice export and the North Atlantic Oscillation is not significant over the studied *** contrast,the association with the cross-gate sea level pressure difference is rob.st in the b.ffin b.y(R equals 0.69 to 0.71,depending on the passages considered),b.t relatively weaker than that over FS(R=0.74).

关键词： sea ice transport b.ffin b.y Arctic sea ice area flux(SIAF)

A Preliminary Study on the Theory of Polar Coordinates Digital Photogrammetry and the Coordinate System of Spatial Information

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Journal of geodesy and Geoinformation Science 2018年第1期1卷 61-79页

作者： Lei YAN Ruihua ZHANG Yanb.ao sun b.ijing key Lab.of Spatial Information Integration and Its Applications Peking UniversityBeijing 100871China Department of Civil Environmental&Geomatic EngineeringUniversity College London(UCL)LondonUK

The development of new aeronautics and astronautics technologies has b.en constrained b. strict mathematical rules for data processing among the diverse methods used to ob.ain spatial *** acquisition of spatial information has b.en affected b. various choices including the applied technologies(e.g.,push b.oom sensors),techniques(e.g.,zoom imaging),and equipment settings(e.g.,swing angle,aerial platform attitude,camera angle)in terms of the convergence,efficiency,and accuracy of the *** on the principle of the b.onic machine parallax angle and pyramidal projection of the aerial space platform to the surface,this study explored solutions for high-resolution image sparsity,ill-conditioned singularity,and non-convergence b. b.ilding a set of mathematical models to process the polar coordinates of the parallax angular *** study also formed a polar information theory for initial spatial *** method improved the ranges of accuracy,efficiency,and anti-interference in close-range photogrammetry and the free net b.ndle adjustment model b. several orders of *** open source code was made glob.lly availab.e more than 3 years ago,and has received positive *** method’s effectiveness was verified using aerophotogrammetry and ab.olute network adjustment model experiments,and its performance was b.tter than that of the Cartesian coordinate processing ***,the higher-order solution characteristics of various applications and spaceflight platforms were provided,which are expected to provide a foundation for construction of a new polar coordinate system for aerospace multi-scale all-attitude spatial information acquisition,organization,management,storage,processing,and application.

关键词： astringency b.onic machine vision convergence precision intelligent photogrammetry polar coordinates vector spatial information

dynamic changes of gravity fields b.fore and after the 2008 Wenchuan earthquake(Ms8.0)

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geodesy and Geodynamics 2012年第3期3卷 1-16页

作者： Shen Chongyang Li Hui sun Wenke Huang Jinshui sun Shaoan xuan Songb.i Tan Hongb. Liu Shaoming key laboratory of Earthquake geodesy Institute of Seismology China Earthquake Administration Wuhan 430071 China wuhan b.se of institute of Crustal dynamics China Earthwuake Adainitration Wuhan 430071 China Graduate University of chinese academy of sciences Beijing 100049 China University of Science and Technology of china Hefei 230026 China

The pattern evolution and dynamic mechanism of the dynamic changes of regional gravity fields occurring b.fore and after the Wenchuan Ms8.0 earthquake are analyzed, b.sed on five epochs of 1998 -2007 mob.le gravity data from the middle-south section of the north-south seismic b.lt, and two epochs of field research data collected after the 2008 Wenchuan earthquake in comb.nation with GPS data, leveling ob.ervations, and geotectonic environment data. The regional dynamic gravity changes demonstrate the effects of the eastward flow of solid matter in the Qinghai-Tib.tan plateau and the preparation of the 2008 Wenchuan earthquake （2- 10 yr）. The two most meaningful gravity indicators of the Wcnchuan earthquake preparation are the positive （increasing） gravity changes occurring over many years in the southwest epicenter and the largescale gradient zone of gravity variation, with the cumulative difference b.tween the two sides of the gradient zone of gravity exceeding 200 μGal. The positive gravity changes may facilitate a constant energy accumulation and the gradient b.lt may support seismic shear b.eakage. Overall, the gravity changes associated with the earthquake preparation indicate a pattern of accelerating increase-decelerating increase-earthquake occurrence. The Songpan-Ganzi b.ock generally displays a negative gravity change, providing evidence for a local upwarp- ing of the deep crust-mantle and an interior expansion of the deep crust attrib.tab.e to high temperatures. The viewpoint is consistent with the dilatant mechanism for earthquake preparation.

关键词： Wenchuan earthquake gravity field dynamic changes mechanism of earthquake preparation post-earthquake

Donald ***,the master mentor:Testimonials from former international students

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Earthquake Science 2022年第1期35卷 67-70页

作者： Xiaodong Song Sidao Ni Ying Tan Alex Song Risheng Chu Daoyuan sun Shengji Wei Semechah Lui Voon Hui Lai institute of Theoretical and Applied geophysics School of Earth and Space SciencesPeking UniversityBeijing 100871China State key laboratory of geodesy and Earth's dynamics Innovation Academy of Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430077China Chevron Technical Center Houston TX77002USA Department of Earth sciences University College LondonLondon WC1E 6BTUnited Kingdom laboratory of Seismology and Physics of Earth's Interior School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Asian School of the Environment/Earth Ob.ervatory of Singapore Nanyang Technological UniversitySingapore 639798Singapore Department of Earth sciences University of TorontoTorontoONM5S 3B1Canada Research School of Earth sciences The Australian National UniversityACT 2601Australia

Don trained many *** over the〜5 decades of his career,at least 45 were advised or co-advised according to a Caltech account.A large numb.r were international students including a high percentage of chinese *** contrib.tors to this article graduated over a time span of 26 years,and we are now distrib.ted in 6 countries across 14 time zones,yet we represent only a small fraction of his former students and postdocs.

关键词： Donald career trained

Gravity inversion of deep-crust and mantle interfaces in the Three Gorges area

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geodesy and Geodynamics 2012年第4期3卷 7-17页

作者： Wang Jian Shen Chongyang Li Hui sun Shaoan Xing Lelin key laboratory of Earthquake geodesy Institute of seismologyChina Earthquake Administration Crustal Movement laboratory

To b.tter understand the heterogeneity of deep-crust and mantle interfaces in the region of the Three Gorges, china, we used the Parker-Oldenb.rg iterative inversion method to invert existing b.uguer gravity data from the Three Gorges area （ 1 ： 500000） , a new gravity map of the Three Gorges Dam （ 1 ： 200000） , and the results of deep seismic soundings. The inversion results show a Moho depth of 42 km b.- tween b.dong and Zigui and the depth of the b. lower-crustal interface b.neath the Jianghan Plain and sur- rounding areas at 21 -25 km. The morphology of crustal interfaces and the surface geology present an over- pass structure. The mid-crust b.neath the Three Gorges Dam is approximately 9 km thick, which is the thin- nest in the Three Gorges area and may b. related to the shallow low-density b.dy near the Huangling anti- cline. The upper crust is seismogenic, and there is a close relationship b.tween seismicity and the deep- crust and mantle interfaces. For example, the MS. 1 Zigui earthquake occurred where the gradients of the Moho and the b. interface are the steepest, showing that deep structure has a very important effect on re- gional seismicity.

关键词： inversion gravity anomaly deep structure the Three Gorges area

1999年集集地震前后台湾地区地震b.及应力场时空演化特征

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地球物理学报 2022年第6期65卷 2137-2152页

作者：高雅婧孙云强罗纲中国科学院计算地球动力学重点实验室北京100049 中国科学院大学地球与行星科学学院北京100049 福建农林大学交通与土木工程学院福州350002 武汉大学测绘学院武汉430079 武汉大学地球空间环境与大地测量教育部重点实验室武汉430079

地震b.时空分布及演化是地震孕育研究及地震危险性评价的重要指标.本文首先基于台湾地区1999年至2005年期间的地震目录数据,对该区进行地震b.时空扫描,得到了台湾地区的b.时空分布,分析了1999年M_(W)7.6台湾集集地震前后b.时空演化... 详细信息

地震b.时空分布及演化是地震孕育研究及地震危险性评价的重要指标.本文首先基于台湾地区1999年至2005年期间的地震目录数据,对该区进行地震b.时空扫描,得到了台湾地区的b.时空分布,分析了1999年M_(W)7.6台湾集集地震前后b.时空演化特征;进一步基于GPS速度场数据估算了地震前后区域的应变率和差应力率分布特征与变化;最后分析并探讨了b.分布、演化与差应力率场的关系.结果显示:(1)集集地震前后的1999—2005年,震中所在地震区的b.呈现出震前降低-震后先升高后降低的演化特征,反映区域应力的累积-释放-累积的过程;(2)集集地震震后的2003—2005年,由GPS速度场数据获得的震源区差应力率较大,意味着差应力累积速率较高,可能与震后中下地壳和上地幔黏弹性应力松弛有关,而相同时间段震源区的b.较高,意味着震源区附近上地壳差应力仍然较低,该时段震后过程仍在持续;(3)台湾西南和东部海岸山脉逆冲作用较强,差应力率较大,而b.较小,均可能意味着其背景差应力水平较高;台湾地区沿中央山脉由北至南存在扩张拉伸作用,差应力率较小,而b.较大,都意味着背景差应力水平可能较低.本文的结果对认知台湾地区地震活动变化、台湾地震孕育过程及地震b.与应力的关系具有重要作用.

关键词：震级-频度关系 b. 台湾地区集集地震应力率应变率

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三种最新全球海潮模型在中国沿海的精度评估

海洋科学进展 2023年第1期41卷 54-63页

作者：周东旭孙维康付海德付延光周兴华自然资源部第一海洋研究所山东青岛266061 自然资源部海洋测绘重点实验室山东青岛266590 山东科技大学测绘与空间信息学院山东青岛266590 山东正元数字城市建设有限公司山东烟台264670

海潮负荷形变是我国沿海GNSS实时观测的重要误差源之一,分析和确定最优海潮模型进行负荷改正,有助于提高GNSS解算精度和可靠性。利用沿海33个验潮站连续3 a的实测潮位资料,以8个主要分潮(M2、S2、N2、K2、K1、O1、P1和Q1)的潮高和方根(R... 详细信息

海潮负荷形变是我国沿海GNSS实时观测的重要误差源之一,分析和确定最优海潮模型进行负荷改正,有助于提高GNSS解算精度和可靠性。利用沿海33个验潮站连续3 a的实测潮位资料,以8个主要分潮(M2、S2、N2、K2、K1、O1、P1和Q1)的潮高和方根(Root Sum Squares,RSS)为评价指标,对最新全球海潮模型FES2014、EOT20和TPXO9在中国沿海的模型精度进行评估。结果表明:3种最新海潮模型相比其前期版本(FES2004、EOT11a和TPXO7.2),在中国沿海的模型精度整体改进幅度分别为72.39%、67.73%和31.37%;3种最新海潮模型中,FES2014在中国沿海的RSS均值和标准差分别为7.91和7.75 cm,模型精度相对最高,EOT20的模型精度略低于FES2014,二者精度均显著优于模型NAO.99jb.NAO.99b.后两处模型在先前研究中被认为在中国沿海精度较优),TPXO9的模型精度则相对较差,仅略优于NAO.99b.同时,分析结果也显示FES2014、EOT20和TPXO9等模型均有其最佳适用区域或地点,在中国沿海GNSS数据精细批处理中,可根据需求选用合适的海潮模型。

关键词：中国沿海最新海潮模型精度评估验潮站和方根

基于D-P算法和最优路径的海山地理实体边界划定方法

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海洋学报 2023年第2期45卷 118-129页

作者：崔丙浩吴自银赵荻能阳凡林刘志豪姚宜斌孙中苗山东科技大学测绘与空间信息学院山东青岛266590 自然资源部第二海洋研究所浙江杭州310012 自然资源部海底科学重点实验室浙江杭州310012 上海交通大学海洋学院上海200030 武汉大学测绘学院湖北武汉430072 西安测绘研究所陕西西安710054 东海实验室浙江舟山316021

海底地理实体的划定与命名是当前国际海洋权益领域的热点研究问题之一。然而,由于海底地理实体边界的量化界定技术缺乏,导致其界线确定不可避免地存在人为性,为此,本文提出了一种基于D-P算法和最优路径的海底地理实体边界划定方法。将... 详细信息

海底地理实体的划定与命名是当前国际海洋权益领域的热点研究问题之一。然而,由于海底地理实体边界的量化界定技术缺乏,导致其界线确定不可避免地存在人为性,为此,本文提出了一种基于D-P算法和最优路径的海底地理实体边界划定方法。将高分辨率水深模型转换为二维水深矩阵,从横向与纵向进行剖面分析,采用极值点简化和D-P算法进行二次简化的方法,通过坡度变化定位和基部高程定位等基本条件综合判断,从而实现了单体海山的山体与其基部的自动划分;在此基础上,采用路径寻优的方法实现了连体型海山的自动分割。该方法在南海海底地理实体划定中进行了验证,取得了良好的应用效果。

关键词：地理实体山脚点 D-P算法路径寻优边界识别

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甘肃临夏机场二维微动剖面探测

大地测量与地球动力学 2023年第12期43卷 1235-1239页

作者：刘白云陈九辉刘云全赵莉孙艳萍中国地震局地质研究所地震动力学国家重点实验室北京市华严里甲1号100029 甘肃省地震局兰州市东岗西路450号730000 甘肃省敦煌文物保护研究中心兰州市张苏滩800号730000 新疆建雅道路建设工程有限公司新疆维吾尔自治区阿克苏地区沙雅县人民北路842200 中国铁塔股份有限公司甘肃省分公司兰州市火星街1201号730050

在拟建的甘肃临夏机场航站楼南面与北面分别布设由圆形台阵观测系统组成的AA′测线与由线性台阵观测系统组成的b.′测线。探测结果显示,在二维AA′视S波速度结构剖面上,微动探测法确定的各地层分层清晰可见,各层层状起伏小、基本近水平... 详细信息

在拟建的甘肃临夏机场航站楼南面与北面分别布设由圆形台阵观测系统组成的AA′测线与由线性台阵观测系统组成的b.′测线。探测结果显示,在二维AA′视S波速度结构剖面上,微动探测法确定的各地层分层清晰可见,各层层状起伏小、基本近水平。用相关区域地勘资料标定可知,以黄土状粉土层代表的第四系覆盖层厚度为120 m左右,完整基岩面埋深在170 m左右。b.′剖面显示的地层结构整体向南倾,这可能与该测线的线性台阵的布局结构有关。2个剖面均显示各地层连续性较好,无明显错断现象,场区应无隐伏断层等不良地质体的存在。

关键词：二维微动剖面微动探测频散曲线地层分层机场工程勘察