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Atmospheric gravity Green's functions

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chinese Science Bulletin 1997年第20期42卷 1712-1719页

作者： SUN HepingLaboratory of Dynamic geodesy, institute of geodesy and geophysics, chinese academy of sciences, Wuhan 430077, china Laboratory of Dynamic geodesy Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China

THE observational accuracy of the superconducting gravimeter has now reached 0.1 μGal levelor better, with characteristics of the low noise, high sensitivity and better continuity and sta-bility. It will play an important part in the study of the change in (non-) tidal gravity signals,especially in the application of the geophysics and geodynamics. However, the instrument

关键词： air pressure Green’s functions atmospheric gravity admittance.

Architecture and application of integrated spatial information service platform for digital mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 706-711页

作者： ZHANG Jin1, XIAO Jie2.1. College of Mining, Taiyuan University of Technology, Taiyuan 03002., china 2. institute of geodesy and geophysics,{2., Wuhan 430077, china Taiyuan Univ Technol Coll Min Taiyuan 030024 Peoples R China chinese Acad Sci Inst Geodesy & Geophys Wuhan 430077 Peoples R China

Using enterprise GIS platform, spatial databases and modern information technology, building geo-spatial information service platform of digital mine which has the features of the data exchange service, enterprise GIS services, directory services, logging services, is key technology and application infrastructure for digital mine. Based on the support of geospatial information service platform of digital mine, the professional GIS application service adapter can be developed and the application supports related to mining application system can be realized. Using high-resolution satellite remote sensing data, the mine functional partition map and geographic grids can be divided, and the geographic grid parts, status and events of important features of the surface object were investigated and defined. The system architecture and technical characteristics of integrated spatial information service platform were analyzed firstly, which guarantee service ability of digital mine. The methods and applications of functional partition map for integrated management service platform were discussed which are the services scheme of digital mine. The application results indicated that digital mine upgrades and enhances the capability and range of mine surveying and mapping, and is of great significance for guarantee of efficient, green and intensive exploitation of mine.

关键词： platform architecture web services application services digital mine

The GPS-gravimetry boundary value problem

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Science china Earth sciences 2005年第3期48卷 398-405页

作者： YU Jinhai1,2.& ZHANG Chuanding2.1. institute of geodesy and {2. of chinese academy of sciences, Wuhan 430077, china 2. Zhengzhou Information Engineering University, Zhengzhou 450052. china 1. institute of geodesy and {2. of chinese academy of sciences 430077 Wuhan China 2. Zhengzhou Information Engineering University 450052 Zhengzhou China

How to determine the earth’s external gravity field with the accuracy of O(T2. by making use of GPS data and gravity values measured on the earth’s surface is dealt with in this paper. There are two main steps: to extend these measured values on the earth’s surface onto the reference ellipsoid at first and then to seek for the integral solution of the external Neumann problem outside the ellipsoid. In addition, the corresponding judging criteria of accuracy to solve the GPS-gravity boundary value problem are established. The integral solution given in the paper not only contains all frequency-spectral information of the gravity field with the accuracy of O(T 2., but is also easily computed. In fact, the solution has great significance for both theory and prac- tice.

关键词： Neumann boundary value problem, integral solution, gravity disturbance.

Determination of vertical gradient of gravity anomaly with topographic data

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chinese Science Bulletin 1999年第11期44卷 1029-1034页

作者： ZHANG Chijuninstitute of geodesy and {2. , chinese academy of sciences , Wuhan 430077 , china institute of geodesy and {2. Chinese Academy of Sciences Wuhan China

The role of vertical gradient of gravity anomaly in the solution and interpretation of geological and geophysical problems on superficial layer is increasingly evident. However, it is difficult to directly observe the vertical gradient of gravity anomaly in mountainous area. Moreover,aerial and satellite gravity gradient measurments have not been put into practice up to date *** vertical gradient of gravity anomaly is calculated by use of topographic data and several problems concerned are investigated and discussed. It turns out in theory and practice that the relative error of the vertical gradient determined with the method is only 5%, and when the vertical gradient of gravity anomaly reaches the maximum 1 000 ns-2./sup> the error is only 50 ns-2./sup>. In addition, how to divide ring zones in calculation and the errors caused by the inaccuracy of landform elevation and rock density has been quantitatively analysed.

关键词： vertical gradient gravity anomaly topographic mass geoid.

General inverse of Stokes, Vening-Meinesz and Molodensky formulae

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Science china Earth sciences 2006年第5期49卷 499-504页

作者： CHENG Luying1,2.& XU Houze1 1. institute of geodesy and {2., chinese academy of sciences, Wuhan 430077, china 2. Xi’an Research institute of Surveying and Mapping, Xi’an 710054, china 1. institute of geodesy and {2. Chinese Academy of Sciences Wuhan 430077 China 2. Xi’an Research institute of Surveying and Mapping Xi’an 710054 China

The operator operations between the disturbing potential and the geoidal undulation, the gravity anomaly, the deflection of the vertical are defined based on the relations among the gravity potential, the normal gravity potential and the disturbing potential. With the sphere as the boundary surface, based on the solution of the external boundary value problem for the disturbing potential by the spherical harmonics in the physical geodesy, the general inverse Stokes’ formula, the general inverse Vening-Meinesz formula and the general Molodensky’s formula are derived from the operator operations defined. The general formulae can get rid of the restriction of the classical formulae only used on the geoid. If the boundary surface is defined as the geoid, the general formulas are degen- erated into the classic ones.

关键词： spherical harmonics, boundary value problem, general inverse Stokes' formula, general inverse Vening-Meinesz formula, general Molodensky's formula.

Improved retracking algorithm for oceanic altimeter waveforms

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Progress in Natural Science:Materials International 2009年第2期19卷 195-203页

作者： Lifeng Bao,Yang Lu,Yong Wang institute of geodesy and {2.,chinese academy of sciences,Wuhan 430077,china [a]institute of geodesy and {2. Chinese Academy of Sciences Wuhan 430077 China

Over the deep oceans without land/ice interference,the waveforms created by the return altimeter pulse generally follow the ocean model of Brown,and the corresponding range can be properly determined using the result from an onboard tracker. In the case of com-plex altimeter waveforms corrupted due to a variety of reasons,the processor on the satellite cannot properly determine the center of the leading edge,and range observations can be in error. As an efficacious method to improve the precision of those altimeter observations with complex waveforms,waveform retracking is required to reprocess the original returning pulse. Based on basic altimeter theory and the geometric feature of altimeter waveforms,we developed a new altimeter waveform retracker,which is valid for all altimeter wave-forms once there exists a reasonable returning signal. The performances of the existing Beta-5 retracker,threshold retracker,improved threshold retracker,and the new retracker are assessed in the experimental regions (china Seas and its adjacent regions),and the improvements in the accuracy of sea surface height are investigated by the difference between retracked altimeter observations and ref-erenced geoid. The comparisons denote that the new algorithm gives the best performance in both the open ocean and coastal regions. Also,the new retracker presents a uniform performance in the whole test region. Besides,there is a significant improvement in the short-wavelength precision and the spatial resolution of sea surface height after retracking process.

关键词： Altimetry Waveform retracking Sea surface height

Spectral analysis of quasi-stationary sea surface topography from GRACE mission

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Science china Earth sciences 2005年第11期48卷 2040-2048页

作者： ZHANG Zizhan1,2.& LU Yang1,3 1. institute of geodesy and {2., chinese academy of sciences, Wuhan 430077, china 2. Graduate School of the chinese academy of sciences, Beijing 100039, china 3. Unite Center for Astro-geodymics Research, chinese academy of sciences, Shanghai 2.0030, china 1. institute of geodesy and {2. Chinese Academy of Sciences 430077 Wuhan China 2. Graduate School of the chinese academy of sciences 100039 Beijing China 3. Unite Center for Astro-geodymics Research Chinese Academy of Sciences 200030 Shanghai China

During the last two decades satellite altimetry has offered an abundance of meas-urements of the sea surface resulting in the improvement of global mean sea surface height (MSSH) and marine geoid determination. On the other hand, with the launching of new genera-tion gravity satellites, some high accuracy long-wavelength gravity models are available. These breakthroughs give us a great opportunity for new estimation of quasi-stationary sea surface topography (QSST). In this paper, the new gravity model GGM01C derived from GRACE mission is briefly presented, and a new global high precision and high-resolution QSST is determined based on the GGM01C model and the global MSSH. The spectral features of the QSST esti-mated by GGM01C and EGM96 gravity model to degree/order 2.0 are discussed by spectral analysis. As a result, the QSST is mainly composed of long waves, medium waves partially and short waves scarcely, its power spectral structures are different between the zonal direction and the meridional direction, there are great differences between the two models, which maybe ex-plain why the ocean currents derived from the two gravity models by Tapley show different pat-terns.

关键词： quasi-stationary sea surface topography, mean sea surface height, GGM01, fast Fourier transform, spectral analysis

Determination of geoid and elevation of the Mt. Qomolangma and discussion on the role of vertical gravity gradient

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chinese Science Bulletin 1997年第20期42卷 1723-1725页

作者： ZHANG Chijuninstitute of geodesy and {2., chinese academy of sciences, Wuhan 430077, china institute of geodesy and {2. Chinese Academy of Sciences Wuhan 430077 China

IT is known that the Mt. Qomolangma is the highest peak in the world. It was recorded in the'Map of Complete Territory of the Qin Dynasty' (published in 1717). As the highest peak,the Mt. Qomolangma not only provokes the interest of climbers but also arouses much atten-tion of geodesists. A significant cause is that the Mt. Qomolangma is located in the collisionbelt between the Indian Plate and the Eurasian Plate. According to the relative

关键词： geoid orthometric height the Mt. Qomolangma.

Plumb line variation at Tangshan during 1987―1998 and its relation with the earthquakes around

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Science china Earth sciences 2009年第1期52卷 101-107页

作者： LI ZhengXin1,2.& LI Hui3 1 Shanghai Observatory,chinese academy of {2.,Shanghai 2.0030,china 2.institute of geodesy and geophysics,chinese academy of {2.,Wuchang 430077,china 3 institute of Seismology,china Earthquake Administration,Wuchang 430071,china Shanghai Observatory Chinese Academy of Sciences Shanghai 200030 China institute of geodesy and {2. Chinese Academy of Sciences Wuchang 430077 China institute of Seismology China Earthquake Administration Wuchang 430071 Chin

Plumb line variations(PLV) at Tangshan during the years of 1987―1998 are determined by using the 46 batch repeated gravity observations of the Beijing-Tangshan *** has been found that PLV at Tangshan are related with the 38 earthquakes in this *** appears that the time of an earthquake around Tangshan is usually quite the same when PLV at Tangshan begins moving in opposite direction.

关键词： plumb line variations network in northern china variations of local gravity field earthquakes