About the accuracy of calculation the main characteristics Earth's gravity field
Journal Title: Геодинаміка - Year 2014, Vol 17, Issue 2
Abstract
Objective. The main purpose is to research the requirements for calculation accuracy characteristics of the Earth's gravitational field (quasigeoid heights and plumb line deflection components) based on an analysis of existing methods and requirements to determine these characteristics. Methodology. Gravimetric method is the primary method for determining the height quasigeoid and plumb line deflection components for land and shelf areas. Initial data in this case are results of the gravimetric survey. The main methods of determining the characteristics of Earth's gravitational field is integral transform methods, parametric approximation methods, statistical collocation methods and combined methods. These methods calculate heights of quasigeoid and plumb line deflection components produce with different results on the accuracy of calculations. Methods of integral transforms based on formulas Stokes and Vening-Meynes amended by Molodensky. When using analytic continuation precision calculation of plumb line deflection components this method reaches 0.5-1" for all regions. Parametric approximation methods make it possible to calculate the characteristics of Earth's gravitational field in the central and close areas(V.I. Aronov method) or incorporation of global and regional characteristics (spherical harmonics method). Statistical collocation method uses statistical relationships between the calculated characteristics of the gravitational field and the initial gravity anomalies, but its accuracy is limited due to the replacement of the true values of kovariations on the model values. In the combined method take into account the impact close areas by gravimetric data using the generalized Stokes integral, the impact of distant zones - using geopotential harmonic coefficients. Results. For practical implementation heights quasigeoid and plumb line deflection components definition geosphere surface is divided into a central area (radius 100 km), close (to 1000 km) and long (the rest of the geosphere) zone. It is necessary to have the presence of input information in the form of gravimetric mesurements scale of 1:50 000 for the central zone and the scales of 1:100 000-1:200 000 for close zones. The input information for long areas are modern digital models of the gravity field of the Earth in the form of harmonic geopotential coefficients. Practical significance. Сalculation of plumb line deflection components should be considered the predominant influence of the central and close areas, quasigeoid heights definition requires a careful consideration of the impact of long areas. For successful application of computation methods of gravity field characteristics must use appropriate gravimetric and topographic information. Originality. Under current requirements, calculations of quasigeoid heights should be accurate to 0.1 m, and the plumb line deflection components - 0.05-0.1". The most efficient and accurate calculating method of these characteristics is combined method.
Authors and Affiliations
P. D. Dvulit, O. V. Smelianets
The influence of the sedimentary strata on the seismic oscillation on the teritory Tashlyk hydroelectric pumped storage power plant
Purpose. The aim of the paper is to study the influence of the filtering properties of the sedimentary strata on the seismic vibrations of construction or operational sites located in the territory of Ukraine. Methodolog...
Geo- and hydro-acoustic complex as a study of interconnection between processes in waters and bottom sediments
The modern native geo- and hydro-acoustic complex usinged as the study of interconnection between processes in waters and sediments as elements of the difficult geo- and hydrodynamic system is proposed. This previous sen...
Statistical features and analysis of tectonic jointing from cretaceous-neogene deposits of the Ukrainian Carpathians
Purpose. Statistical features and the distribution of the data orientation over 8 000 tectonic joints from flysch and molasses deposits of Skyba and Boryslav-Pokuttya nappes with some statistical parameters (K, C) are de...
Geological and paleooceanographic models of the Carpathian-Black Sea continental margin of the Tethys
Purpose. To clear up geological-paleooceanographic conditions of sediment-lithogenesis of the Mesozoic-Cenozoic deposits of the Carpathian-Black Sea continental margin of the Tethys. Methodology. Multi-aspect complex app...
Mathematical simulation of frequency sounding with electromagnetic field in a locally inhomogeneous half-space
Purpose. In order to adequately describe real processes that characterize the spread in the crust harmonic electromagnetic field (EMF) excited by artificial sources , unlike classical models (homogeneous and piecewise ho...