Scientific Computation Platform for Geophysical Geodesy

Integrated nearly 20 years of geodetic research results, the large scientific computing window platform for geophysical geodesy have been independently developed by Chinese Academy of Surveying and Mapping, which is composed of PAGravf4.5 (Precise Approach of Earth gravity Field and geoid) and ETideLoad4.0 (Earth Tide, Load effects and deformation monitoring computation). Based on the purpose of public welfare, the scientific computing platform is committed to improving the scientific research and higher education environment lacking in such computing resources in the geoscience field, showing the attractive potential of geodesy, reconstructing the heterogeneous geodetic system and collaborative geodetic frame, and improving the geodetic ability in multi-disciplinary collaboration and solving practical problem.

Precise Approach of Earth Gravity Field and Geoid (PAGravf4.5) is a large scientific computation software package according to stationary gravity field theory. Which constructs the unified analytical algorithm system of various terrain effects on various types of gravity field elements outside the geoid to improve the geophysical gravity exploration and gravity field data processing. Sets up the complete gravity field approach algorithm system according to the geodetic boundary value theory to realize the full elements modeling of gravity field and 1cm accuracy of geoid. Develops some ingenious algorithms according to physical geodesy to optimize regional height datum, and then expand the geodetic application from gravity field method and data.

PAGravf4.5 has a strong analysis ability on various physical geodetic issues and can directly measure the external accuracy of gravity field observations. You can call the programs to verify the performances of the relative algorithms and nature of gravity field from the observation situations to design high-performance solutions in advance, and then calculate various terrain effects, fuse heterogeneous observations, model full elements of gravity field and land-sea geoid, and refine regional height datum.

Earth Tide, Load Effects and Deformation Monitoring Computation (ETideLoad4.0) is a large software package for scientific computing of geophysical geodetic monitoring. Which adopts the scientific uniform numerical standards and analytic compatible geophysical algorithms accurately to compute various tidal and non-tidal effects on various geodetic quantities outside the solid Earth, approach global-reginal load deformation field and temporal Earth’s gravity field, and then quantitatively monitor surface hydrology environment, ground stability variations and geological disasters, in order to promote the collaborative monitoring of multi-geodetic technologies and deep fusion of multi-source heterogeneous geodetic data.

You can design your own schemes and processes, then organize flexibly the related programs and functions from ETideLoad4.0, perform some scientific computations for various tidal or non-tidal effects, ground deformation field or temporal gravity field, land water, ground stability, or surface dynamic environment monitoring, and multi-source heterogeneous geodetic data deep fusion.

The two software packages were developed by QT C++ (Visual C++) for the user interface, Intel Fortran (Fortran90, 132 Columns fixed format) for the core function modules, and mathGL C++ for the geodetic data file visualization in the Visual Studio 2017 x64 integrated environment. PAGravf4.5 is composed of nearly 50 win64 executable programs with more than 500 function modules, and ETideLoad4.0 is composed of more than 50 win64 executable programs with nearly 600 function modules.

The scientific computing platform is suitable senior undergraduates, graduate students, scientific researchers, and engineering technicians in geodesy and geophysics, geology and geoscience, geomatics and geographic information, seismic and geodynamics, aerospace and satellite dynamics. Which can be employed for the classroom teaching, independent self-study, applied computation and scientific research. You can design your own schemes and processes, then organize flexibly the related programs and functions, perform some scientific computations for geophycical geodesy.

There are the example files saved in the folder C:\PAGravf4.5_win64en\examples and C:\ETideLoad4.0_win64en\examples for each Win64 program, espectively. Each example includes the operation process file processinf.txt, some input-output data files and screenshots. The folder name of the example files is the same as the name of the window executable program.

Before the program to be used, it is recommended to run the program from the input-output example data files with comparing the screenshots and the process information in processinf.txt. It will take about 5 working days to complete all the example exercises for PAGravf4.5 or ETideLoad4.0. Thereafter, you can use the scientific computing platform alone.

PAGravf4.5 structure of computation functions
ETideLoad4.0 structure of computation functions
Principle of heterogeneous geodetic data fusion

(1) Using scientific consistent geophysical models, rigorous uniform numerical standards, and analytic compatible geodetic and geodynamic algorithms, construct the theoretical basis and necessary conditions for geodetic collaborative monitoring by unifying the spatiotemporal monitoring frames and reference epoch.

(2) For the same type of multi-source heterogeneous geodetic monitoring quantities, the basic geodetic constraints or joint adjustment methods with additional monitoring datum parameters as needed are used to deep fusion.

(3) For different types of monitoring quantities, physical geodetic, solid geophysical, or environmental geodynamic constraints with additional dynamic parameters as needed are used to deep fusion.

(4) The purpose of reconstructing the geodetic or geodynamic relationship between various monitoring data is not only to improve the spatiotemporal monitoring capability, but also to further reveal the geodynamic structure and characteristics of the monitored objects.